July 26, 2022 • 53 mins
We all think we know the basics of weight loss. It is all about consuming fewer calories than you burn. Eat less, move more. Calories in, calories out. But there’s much more to it than these simple equations, as a trip to the enormous Pennington Biomedical Research Center in Baton Rouge, Louisiana - a hub of such research - shows. In this episode, we break down the science of why it’s so hard to lose weight, and look at what the kinds of stories heralded as a weight-loss success really look like in practice.
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Speaker 1 (00:01):
One of the first things I noticed when I walk
into Pennington Biomedical Research Center is a giant stained glass window.
It's filled with images of healthy living cast in rainbow colors.
You see there are two wheels here, and there is
a cyclist on on the top, and then there is
(00:22):
all kinds of fruits and vegetable. I mean, it's it's
quite a nice piece of art. The stained glass window
towers above a Pennington entryway. Brightly colored shards of glass
depict asparagus, bananas, peace, and a pineapple. The outline of
a runner cuts through the background, painted in shades of
(00:45):
orange and purple. And then there's a DNA DNA on
the right. There are blue and pink fish at the bottom,
canteloupe on the side. The longer I stare, the more
bowls of healthy living reveal themselves. But it's all about
what we do. I mean, you know health, genetics and biology,
(01:09):
and you have you have all the elements of nutrition,
you have the exercise, you have the d n A.
The whole thing makes the place feel like a temple
to nutrition, because it kind of is. Pennington is a
sprawling research center working to study obesity. Our tour guide
(01:30):
today is Eric Ravasan, a prominent scientist in the space
who is Associate executive director for Clinical Science at Pennington.
He's the one talking me through all of the stuff
in this very large stained glass window. Stained glass is
obviously more a feature of churches, but the religious symbolism
(01:53):
is sort of fitting. Really, this is a place that
treats weight loss as a sort of gospel. Pennington has
two acres of campus, including labs and research facilities, around
two hundred scientists and state of the art equipment, much
of it dedicated to unlocking the secrets to shedding pounds.
(02:19):
It's in Baton Rouge, Louisiana, and it feels like a
college campus minus the students. I've been on a journey
to get to the bottom of the science of weight loss,
and as our stained glass windows shows, weight loss is
something we all have lots of ideas about. Some of
(02:39):
those ideas are actually true, but they're all too often
not the whole truth. If anyone could help us sort
one from the other, I figured it would be the
people here. First, though, We're going to take a look around.
That's part of the way you test. Participants are like,
we're walking up to the fourth floor. Yeah, we got.
(03:03):
Our first stop is to check out some fairly innoxious
looking medical machinery. It's big and gray and looks almost
like a bed. And is this the machine beginning now?
It started already. Radiation is on right now because you
can see the lagser on saying in a radiation is
that this equipment can actually tell you how much of
(03:24):
your body is fat, and how much of it is muscle,
and how much is bone. I want to call it
a nightmare machine. It's the scan no one wants to
see of themselves. But what this equipment really measures is
body composition. And the total of this person here is
(03:46):
thirty points six of the body is fat. We often
talk about the number on the scale like it's the
only thing that matters, but this is a good reminder
that wheat isn't every thing. That's why weight loss researchers
use tools like these body composition machines. And a big
(04:08):
finding they've had is that people vary a lot. People's
bodies are different, really really different, and that's actually at
the root of a lot of the findings they've made
here at Pennington. But first, back to the tour, We
check out a big area known as a metabolic kitchen,
(04:31):
where calorically precise foods are prepared for studies, and we
walk by spaces that look like hospital rooms. They're also
used for research. Eventually we get to the craziest stop
on the tour. We step into a hall that looks
into small furnished rooms to seek a curtain and the
(04:58):
bed and you have everything could be happy, and there's Stevie.
They look like really sad studio apartments. Even though there's furniture,
the rooms are sterile looking. There aren't exactly many homey touches.
That's because they're actually rooms where scientific research happens. They're
(05:20):
called metabolic chambers, and they measure metabolism. Like the name suggests,
these sad little rooms are designed to measure how many
calories the person inside is burning. People stay in them
for a good chunk of time, thus all the furniture.
Eric also points out that they have windows. We fast
(05:41):
the food and uh and you know through here outside
of the metabolic chambers, in the hallway where we're standing,
a bunch of pipes and scientific instruments line the walls.
It kind of looks like a boiler room or something.
This equipment track everything going on in the little rooms.
(06:03):
Cool right, Maybe a little creepy too. Eric tells me
that there are only about thirty metabolic chambers in the
world thirty, and Pennington is home to four of them.
When we arrive, there's actually a woman in one of
the rooms already. She's sitting on the bed. It looks
(06:25):
like she's scrolling on her phone. Maybe in a little
while she'll go use the adjoining toilet. Watching the stranger
live her life in a little box while equipment measures
what's going on inside her body is pretty weird, Even
if it is for science. The whole thing feels a
(06:46):
bit dystopian. It makes me think of like a lab
rate in a maze or something. Now she probably can't
see this, but a computer screen right behind Eric and
I actually shows how many calories she's burning on a
minute by minute basis. A chart shows us how that
(07:06):
rate is changing over time. Eric tells me that while
the woman slept, she burned just under a calorie a minute.
Then I would say she got up here. He's saying
that because we can see on the screen that at
this point her metabolism jumps. People tend to burn more
(07:28):
calories as they become more active. She went to brush
your teeth, you know, metabolious me here goes to three
calories a minute. Then you can see and at the
end of the day we summarize how many calories she
has doing. The real work of the metabolic chamber is
happening silently in the air, because the chamber is actually
(07:50):
tracking how much oxygen the woman in the room is
taking in and how much carbon dioxide she's breathing out.
I Well, both oxygen and carbon dioxide are involved in
the process of converting food into usable energy. A little
math and toda, you have calories burned. This is all
(08:16):
part of metabolism, something we usually think about only in
terms of how fast we gain or lose weight, and
that's definitely part of it, but metabolism is also what
keeps us alive and kicking, something that we should celebrate
not blame. You know how people are always talking about
(08:41):
calories in calories out. A metabolic chamber is a very
precise way of calculating the calories out. Part. Technology like
this is really important at places like Pennington where researchers
are digging into the secrets of weight loss. And by
the way, some of what they've learned, is that calories in,
(09:05):
calories out is not the whole story, not by a
long shot. I asked Eric what to make of the
numbers the metabolic chamber is spitting out? Would another person
burn three calories a minute doing the same things as
the woman in the room just now? Like? Did I
burn that much getting ready this morning? That seems like
(09:28):
really interesting and even important data to have about yourself.
If any given way, sex page, and body composition, you
have large variability in between people. Metabolism differs a lot
by person. In other words, Eric couldn't really say if
I or another person would burn as many calories a
(09:50):
minute as the woman in the room. But he tells
me about some research he did way back in the eighties.
We measured people like in the chambers, re measured them
five years later and looked at the relationship between the
metabolism and the weight gain. They gain a lot of weight,
and we found that a low metabolity create is a
(10:12):
risk factor for weight game, otherwise known as I have
a slow metabolism. People love to say I'm gaining weight
just because I have a slow metabolism. But when we
say that, do we really know it for sure. No, no,
that you have to measure it. You have to get
into one of the sad little rooms. Metabolism isn't a
(10:34):
straight line. It can change over your lifetime, including as
you age and when you lose weight. Researchers have learned
more about that in recent years, and it may help
explain why dieters overwhelmingly regain weight over time. We'll get
more into this later. We walk by another suite of
(10:58):
rooms with a tread mill and stationary bike. Researchers use
these to push people to their exercise limits. It's kind
of like a stress test done by a cardiologist, except
even more intense. Nearby, a person is actually getting biopsies
taken of her fat and muscle. I watched the lab
(11:21):
tech sitting at her microscope work on a sample. There
are actual fat and muscle cells in front of her.
Is there anything you can't measure here? When it comes
to UM two, obesti, diabetes and cardiovascular disease. I think
we have it all. One of my co league used
(11:44):
to say, it's like toys are us for a kid? Uh,
you know, it's toys are us for a scientist? So yeah,
you're probably realizing by now that this is a place
with incredible resources fort etting weight loss. And the thing
about weight loss is that we all kind of think
(12:04):
we know the basics. Losing weight is about eating fewer
calories than you burn calories in calories out right. In
this episode, I'm going to get to the bottom of
what we actually know the science of weight loss. How
it's actually a lot more complicated than that simple formula.
(12:27):
And we're going to try to figure out why, why
it's so complicated, and why despite that the simple formula
of calories in calories out keeps getting repeated anyway, not
just by your neighbor or uncle, but by doctors and scientists.
(12:48):
To do that, we'll start this mecca of weight loss,
but we'll go beyond its walls too. I'm Bloomberg News
health reporter Emma Court and from the Prognosis podcast. This
is Losing It. Imagine that you're at the doctor's office
(13:21):
and they tell you to step onto the scale, which
they invariably do visit after visit. That number is measuring
not just your bone, muscle, and fat, but also possibly
your lunch from earlier, your shirt and pants, maybe some
p You can't talk about weight loss without first, making
(13:43):
sense of weight itself. And what doctors and scientists are
concerned about is not your clothing or undigested chopped salad,
or even your bone and muscle. They're worried about fat,
and specifically a person having too much. So how does
(14:03):
a person get more body fat? That comes back to calories,
which we went deep on in our first episode. Remember,
calories aren't just align on a nutrition label. They are
source of energy for your body. Calories are the gas
in your cars fuel tank. Every day we're taking from
(14:24):
that tank because we gotta um, we gotta move. This
is Leanne Redman. She's an expert in physiology or how
human bodies function, and she works for Pennington. We've got
a digest food we think we just function to every day,
we've got energy going out of the tank. So every
day we have to replenish the energy going into the
(14:45):
tank to keep your weight the same. Ideally, you'd be
eating around the same number of calories that you burn.
Lean says, there's a little wiggle room here of about
a few hundred calories a day. But eat too many
calories for too long and that energy has to go somewhere.
(15:06):
It gets stored in the adipose tissue in the body fat,
and then we gain weight gain atiposity of a time,
and that eventually leads to obesity. In other words, fat
is another store of energy. We've demonized it the same
way we've demonized metabolism, but it actually serves this and
other really important functions. Still, extra fat can put a
(15:31):
lot of stress on your body. That's why doctors and
scientists worry about people having too much fat. A quick
note about language here. We will be talking a lot
about weight in this episode, in particular because of the
stigma and bias about this subject. There are different schools
(15:53):
of thought about how to talk about it. The fat
Acceptance movement embraces the term fat. Some doctors and scientists
favor saying person with obesity. I will talk about it
as much as possible the way people do themselves. I
have tried to avoid the terms overweight and obese, though
(16:15):
I have had to use them at times for clarity's sake,
times like now. Obesity is usually defined as when a
person's body mass index is over thirty. As a refresher
b M I equals weight divided by height squared. The
number is supposed to be a proxy for body fat.
(16:37):
But as the formula I just rattled off makes clear,
b M I doesn't actually rely on your body's measured
fat composition, just weight and height, and b M I
is what's overwhelmingly used to talk about weight, like when
rates of obesity in the US began increasing in the eighties.
(16:59):
Around this time, government stats show that nearly six of
American adults were considered too heavy increase from an earlier period.
That judgment was made using b M I, and it
keeps being made using b M I, and it tells
us that Americans keep getting heavier. Today, nearly three quarters
(17:24):
of adults are considered by the government to have higher
than normal weights. So again, calories matter because extra calories
can turn into fat. It's that saying that you've heard
so many times before, calories in calories out. This is
also something we've known for a long time. When you
(17:46):
eat just enough food to supply the energy you need,
your white stays the same. But when you eat more
than you burn up an energy, the rest is starred
as fact. So is it really just that simple calories
in calories out. The answer is yes, sort of ish,
(18:08):
not exactly. Calories in calories out is true, but it's
also not true. If you're lost right now, that's okay.
I promise it will all make sense by the end
of the episode. Remember, we came here to Pennington for
a reason. We wanted to sort out when it comes
to wait, what's fact, what's fiction, and what's still a mystery?
(18:33):
So how do we know that calories in calories out works?
When you walked through this thing that looked like a
medical ward to get to the metabolic chambers. This is
Owen Carmichael. He runs the Biomedical Imaging Center at Pennington.
So basically some of the fancy machines we've been looking at,
(18:55):
we've actually had studies where people live there and they
sleep in the hospital like beds. They're living in a
what looks like a hospital where they're interacting with a
lot of nurses and um that they do not have
a refrigerator that they have free access to. They cannot
order up snacks. They're in a controlled environment. They're being
(19:18):
given calorically precise meals. The sprawling Pennington Gym is nearby.
For some people, this might sound like the ideal conditions
to diet, the v I P diet life, and that's
exactly what the scientists intended for other people. Of course,
this might sound more like torture, but anyway, Pennington researchers
(19:43):
have found that they really, honest to goodness, lose weight,
and they lose fat, not muscle, So it's good weight loss.
People lose weight, at least they do when they spend
that whole time at Pennington. But you can't do that
for a really long time. Study participants have lives to
(20:05):
get back to, and it's exactly when they do that
step outside the boundaries of Pennington out into the real world,
that the trouble begins. I think it's very difficult to
really wrap your head around how seven this thing we
call the obesogenic environment is that scientists speak for the
(20:28):
kinds of unhealthy environments that surround us every day. The
Danish cart on the corner by your office, not having
a grocery store in your neighborhood, living somewhere with lots
of cars but no sidewalks. If you're lucky enough to
have enough to eat, the world can sometimes seem like
it's shoving a plate of fries down your throat. Seven.
(20:53):
And while you have some limited ability to decline, that
metaphorical plate of fries. Not everything is under your control.
We've all experienced this. I even saw it when I
was visiting Pennington for this episode. Here I was speaking
with scientists all day long, talking about the importance of
(21:16):
healthy eating and portion control and cooking food at home.
And meanwhile, I'm staying in a hotel and eating literally
all of my meals out. And did I mention that
Pennington is based in Louisiana A fantastic lace into like
a little peopood. This is a place essentially a full boy.
(21:40):
I like my overflowing with brad shrimp. That thing is
as big as you. Everywhere I went, I kept ordering
food without realizing that it was all deep fried. I
was at lunch one day with a bariatric surgeon who
works at Pennington, and the waiter rattled off a long
list of very fried recommendations. Again, my dining companion here
(22:06):
does weight loss surgery for a living. It was kind
of surreal. When we finished up, they actually brought us
a plate of cotton candy, which we had not ordered
for free. And it's not just the environment around us
that's making things difficult. It can be us too. Here's
(22:27):
leanne again, So it is definitely ultimately about this imbalancing calories.
But it's very, very complicated, right because there are so
many factors that determine what we eat when we you know,
where we're craving something, whether we're full, whether we're hungry
or not. And then on the other side, when you
(22:49):
reduce people's calories, they're like, oh, I'm eating less, so
I'm gonna like, I can, you know, move less? Right,
So they start conserving calories and maybe not as physically active.
The same is true when people are exercising more, they
need more calories, and when people start eating less, our
bodies respond to that. Remember that calories aren't some inconvenient
(23:13):
aspect of oreos their energy. When you have less energy
coming in, your metabolism slows down. That actually makes sense
if you think about it. Your body is now smaller,
so running it moving it around that takes less energy,
(23:35):
kind of like how smaller cars can be more fuel efficient.
But studies of contestants on the TV show The Biggest
Loser have found that metabolism can drop even more than
you would expect. Pennington researchers were actually involved in those studies,
including Eric Ravesson, who took us on the tour earlier,
(23:56):
but we we measured all the people from this season eleven.
He was quite a riot to go to the ranch
outside in California. There's a name for this phenomenon of
metabolism slowing more than expected after weight loss. It's called
metabolic adaptation. Scientists have also found that after weight loss,
(24:20):
hormones that regulate hunger and weight can get disrupted for
long periods of time. These hormonal disruptions and metabolic adaptation
could help explain why so many people regain weight after dieting.
In other words, a person goes on a diet, they
(24:43):
regain the weight later, and people assume it's the dieter's fault. Right,
It seems pretty logical. After all, they say, oh, she
stopped eating as many salads, or that he stopped going
to the gym as much, and maybe they say even
more unkind things than that. But here's the thing. Scientific
(25:08):
research tells us that there may actually be a biological
reason for those things happening. That a dieter could be
getting really hungry because of hormonal disruptions, that their body
might actually be burning way fewer calories after weight loss.
When I first learned about this, It kind of blew
(25:29):
my mind because there seems to be a scientific explanation
for why so many dieters regain weight over time. Your
body is actively fighting back, and that actually makes sense
if you think about evolution, because bodies need energy to live.
An energy used to be a lot harder to come by,
(25:51):
so at the end of the day, it does come
down to the energy imbalance, the intake, and the expenditure.
You have to be out of balance in order to
change weight. But it's all of these other physiological signals
that are driving the intake and the expenditure that we
need to understand better in order to be able to
achieve weight loss for everyone. We're simplifying the science here,
(26:14):
but needless to say, these are complicated things to study,
and it helps to have a dedicated research facility like
Pennington with all its bells and whistles focused on it.
Remember how earlier I said that Pennington feels like a
college campus. It's actually officially part of Louisiana State University,
(26:37):
which is also in Baton Rouge a few miles away.
Back in the nineteen eighties, the head of l s
U got the billionaire oilman Claude Bernard Pennington to commit
hundred and twenty five million dollars to start a nutrition
research center. Over the decades since, the center has been
(26:58):
involved in some of the most cordant research done about
weight and weight related conditions at the Pennington Biomedical Research
Center Biomedical Research Center. Researchers from the Pennington Biomedical Research
Center in Louisiana found Pennington Biomedical Pennington Biomedical Research Center
Pennington Biomedical Research Center in Baton Rouge, So to summarize, studies,
(27:20):
including ones done at Pennington, have shown that when people
eat less, they lose weight. Calories matter pretty self explanatory,
but as we just talked about, calories also aren't the
full story. There's this big gulf between what happens in
research studies at places like Pennington with its gadgets and gizmos,
(27:44):
and the real world. And scientists are also still learning
more about how your body seems to fend off long
term weight loss. So what is all this add up to.
It means that weight loss is more complicated than advertised,
a lot more complicated. It also means that losing weight
(28:06):
isn't fully in a person's control, even though that's how
we tend to talk about it. Reasons like this are
why scientists and doctors have started to call obesity a
disease the same way that diabetes and cancer are diseases.
And if obesity is a disease, dieting takes on even
(28:28):
more importance. It's not just a way to lose weight,
but also a form of medical treatment. And if diets
are medicine, surely we know what the best diet is
for a person. Right the Great diet debate, low carb
or low fat, high fat diets actually may be superior
(28:51):
to low fat diet. In the low carbohydrate groups, they
lost about two and a half to five pounds more
than those in the low fat diet crew. Carbohydrates are
the single most important thing you can eat for health
and weight loss. And you're thinking, right now, Dr Hyman,
have you gotten nuts? Practically each decade has had a
(29:13):
new dietary villain. First fat was bad, and then carbs
were bad. Now I think maybe they're both still bad,
but so is sugar too. Right where did we land
on all that? I'll answer that in a minute. First though,
back to Pennington. As I spoke with scientists at the Center,
(29:36):
I kept feeling like I was going in circles. They
would tell me how complicated weight loss turns out to be.
Now there's so much variability between people, and not just
with burning calories, but in terms of how easily people
lose or gain weight. Now there's still so much scientists
are learning. And then I would ask them, well, what
(29:58):
should people do if they want lose weight? And they
would say, diet, eat fewer calories. And so I'm going
to get the person to write down everything that they
eat and drink for the next five days, and we're
going to look at where the excess calories are coming from,
and we're going to start there. I told Leanne how
confused I was by this. How can it be more
(30:20):
complicated than calories in calories out? But also that calories
in calories out is the answer. And then leon tells
me something that just might haunt me forever. Remember our
metabolic chamber from earlier, the sad little rooms. She and
her colleagues at Pennington did a study where they put
(30:40):
people in there, and the scientists actually over fed these
people on purpose. They gave them more calories than needed.
They were trying to make them gain weight, and this
is what they learned. Some people will burn majority of
the excess calories that they've eaten, and they're the people
(31:01):
that will retaine their weight. Some people will burn, will
burn those extras, some people will burn none. And Leanne
says they've also found that the opposite is true. When
you give people less to eat, some people lose weight
immediately and others just don't. In other words, it's calories in,
(31:25):
calories out, but only for some people. So what I'm
taking away from all this is, if you are a
person who wants to lose weight, we don't have great
information for you dieting calories in, calories out best. We
have another way of putting all this is other people
(31:47):
get to eat as many honey buns from the vending
machine as they want and just burn it all off.
But you don't. By the way, there are other options
for weight loss besides diet, like medication and surgery, but
they're used a lot less. I was struck by what
(32:08):
Leanne said. Though, for all the new fingled machinery and
fancy gadgets we toured earlier, the answer is that we
still don't have an answer. Even though dieting doesn't work
in a long term way for many people, dieting is
still the best we've got, and yet the dogma is
(32:28):
still why don't you just diet? No uncertainty, no caveats,
none of the nuance we uncovered here at Pennington. I
asked Leanne about the uncertainty about the lack of sufficient
answers a couple of times, until finally she said this.
You know, we've spent billions of dollars trying to understand
(32:53):
obesity and white management and how it a fixed people
and how we can help people, and it just seems
like it's all going to a black hole because you know,
even with that huge investment, we have no answers. You
just heard Leanne Redman, an expert in physiology at Pennington,
(33:16):
saying that despite all the money that's been invested in
weight loss, not to mention all the fancy equipment and
scientists who have spent their careers working on the subject,
we have no answers. We have no answers. In fact,
that's exactly why we keep coming back to diets. They're
(33:37):
not the answer, but they are the closest we've gotten
to an answer. Then again, there are a lot of
diets out there. The South Beach diet low fat whole thirty,
So so many diets, which ones actually work the best?
(33:58):
I put the question to Christopher Gardner, a nutrition scientist
at Stanford. This is a super depressing answer that nothing
works because we haven't resolved the obesity epidemic. I know,
this is getting really frustrating, right. One of the things
that we do know is that there isn't one diet
for everyone. So people who claim that it's my diet
(34:21):
or it's the Paleo or the Kido or the something else,
I just it's not true. Let's say I invented a diet,
it's named after me, obviously, and I go around telling everyone, look,
this is the diet that's going to finally make you
lose weight. Basically, what I'm saying is I tried Emma's
(34:43):
diet and it was awesome, and everybody should try Emma's diet.
And what I do as a scientist is I get
a hundred people and I signed fifty two Emma's diet
and fifty to the other diet. And I have to
see that, yeah, way more people on diet A work
than DIETETE and you really doesn't happen. And so what
we found is that there isn't one diet for everyone.
(35:05):
The big problem is keeping it up. I don't eat
carbs until I'm craving them so much that I give in.
I don't eat out until it starts crushing my social life.
All diets have at least this in common. What's the
best diet to be on? It's the one you can maintain.
In other words, if you can keep up a low
(35:26):
carb diet, power to you, same for a low fat diet.
But how do you know at the outset which one
is going to work for you. That's where lots of
scientists across this field are now channeling their efforts. The
consensus now is that diets should be individually matched a
person based on different factors about them, kind of like dating.
(35:51):
My diet biography might say I'm a court journalist, sits
at a desk all day, works out a few days
a week, loves her kale salads, sweet tooth. But there's
still a lot missing from that description, things that I
couldn't tell you, and even Pennington scientists can't use right
now to match me to a diet, Like what's going
(36:15):
on in my gut microbiome that's the collection of bacteria
involved in digestion and metabolism. What about my genetics? Those
are factors that could help you match a person better
to specific diet or what's known as precision health. But
it's very hard to find the genetics or the metabolism
(36:39):
so far that would point you to one diet or another.
We're not there yet, not by a long shot. Scientists
are trying to figure it out though. In fact, the
National Institutes of Health is just starting to fund a
study about this. So again, low fat diets aren't the
(36:59):
best diet it for everyone. Neither is low carb diets
may have to be tailored to the individual. All the
research on dieting and weight loss over the years has
brought scientists to this conclusion. I know, I know. But
the thing is, for all we don't know about weight loss,
(37:21):
there are some things we do know. We actually know
a fair amount about the people who lose weight and
keep it off, what they do, and what it takes.
There was a sense of it's pretty hopeless, uh and nobody,
nobody really succeeds in weight management. If you're a based
you're just out of luck because you know there's not
(37:44):
much you can do about it. People try to diet
but it doesn't work. That was James Hill, who is
Chair of Nutrition Sciences at the University of Alabama at Birmingham.
He's talking about how in the late nineteen eighties rates
of obesity began rising very suddenly. Remember we talked about
this earlier, how those rates had been stable beforehand, but
(38:08):
they've risen and risen until today. And again, as all
this is happening, people are feeling pretty hopeless about losing weight.
So James and his colleague Rena Wayne, who is a
professor at Brown University's Medical School, decided to start tracking
successful dieters. They created the National Weight Control Registry, which
(38:32):
people can join if they have lost at least thirty
pounds and kept it off for at least a year.
There are more than ten thousand members today. James says
that the Registry was supposed to answer a key question,
what does it take to lose weight long term? And
the Registry has actually provided some answers, as evidenced by
(38:57):
thirty scientific papers James and his colleague have written about it.
That's right, we know what it takes to lose weight
long term. You just have to diet and exercise and
prioritize it every single day and worked really hard forever.
(39:22):
So one of the things I always tell people that
we've learned from the National Wake Control registreet it takes
a lot of conscious effort for these people to stay successful.
So it's not the case that they lost weight and
then they went back to living your lives and didn't
think about it. You might remember from our last episode
that this is a diet myth the South Beach Diet
(39:44):
helped spread in the two thousands. They prioritize their weight
very very highly. Of all the people who diet, and
there are many, very few of them actually end up
joining the Red Distry. We'll talk about that more in
a bit. First, though, here's what we know about people
(40:07):
in the National Weight Control Registry. Most of them eat
a relatively low fat diet, but some people do the
low carb thing too. Again, the specific diet doesn't seem
to matter that these folks. Diet seems to matter more
than what kind of diet. Most of them spend probably
(40:29):
more time than the average person thinking about their diet
during the dash, thinking about what they eat, keeping track.
A lot of them keep diet diaries, so they pay
attention to the food they eat. National Weight Control Registry
members weigh themselves every day. They track what they eat
(40:49):
and how much physical activity they get. They're also all
exercising about an hour a day. Jane Fonda and eighties
exercise icon wanted everyone to feel the burdens, not just
National Weight Control Registry participants. If you're thinking that an
(41:12):
hour a day is a lot of exercise, you're right.
The US government recommends a few hours of exercise a week,
and most adults aren't even doing that. I spoke with
five members of the National Weight Control Registry for this
episode and heard similar things for starters. Nearly all of
(41:35):
them exercise intensely most days, and a lot have adopted
some pretty extreme habits to keep their weight off over time.
One guy I spoke with, his name is Marcos Goodman,
told me that he had lost sixty five pounds eight
years ago. To keep it off, he eats the same
(41:56):
five or six meals every day so he doesn't have
attract different foods, like for breakfast, oatmeal with flax seed
and sesame seeds, a banana and some non fat milk,
a stew for lunch made of either sardines or chicken,
and then an evening meal of soybeans. Another woman I
(42:18):
spoke to, Susan Pierced Thompson, lost sixty pounds eighteen years
ago and then since then maintained her weight by cutting
out flour and sugar completely. Susan ended up starting her
own weight loss program based on those ideas. But the
thing that struck me the most was the mental and
(42:39):
emotional energy all these people spent on simply maintaining the
weight that they had lost. It just became this big
part of their lives. For some of them, their lives
even sort of seemed to revolve around this one thing.
No one ever says, this is going to be really painful.
(43:00):
You better get ready because you are going to suffer.
No one ever says that, and I did suffer tremendously.
This is Desha Gill, a fifty six year old stay
at home mom who lives in Dallas, Texas. She's talking
about the process of losing weight what it was like
(43:20):
for her. I don't know if you've ever tried to
sleep when you're really really hungry, not just wanting to eat,
but truly feeling like you're starved. That's how I had
to feel every night. Disia says she has struggled her
weight since she was eleven years old. She told me
(43:40):
that she started off binging on candy bars at summer camp.
I was always very interested in health and longevity, and
I wanted to be active and athletic, and but who
I felt like and what I looked like could not
have been anymore opposite. And I found it humiliating and
(44:04):
embarrassing to look at myself and for people to see
how I would. I was repulsed and so ashamed all
the time, all the time. Desha says she has probably
read hundreds of weight lost books. She has tried weight watchers,
(44:25):
Jenny Craig over eaters anonymous, she got a lap band,
a surgical procedure that constricts the stomach. She even tried hypnosis,
none of it worked. She also says she experienced health
issues that seemed related to her weight, like fatty liver disease,
and asthma. Desha knew she needed to make a major change.
(44:50):
She begins shifting how she eats and ends up losing
a hundred and ten pounds, But she's also raising suns,
which means lots of tempting foods in the house. I
did research and found these food safe that have timers
on them, and so I bought some food safe so
(45:12):
that I could put the food that I had trouble
controlling myself with those food staves, so that my son
and this could get them, or if I wanted to
treat at some point, I could time it so that
I couldn't get into the food safe until I said
that I could. Disha still uses those food saves. They're
(45:32):
made of plastic and have a dial at the top.
She sets them to unlock over periods of hours or days,
so she can't eat, say, candy or chocolate whenever she wants.
She also keeps a fridge near her bedroom in case
she gets the urge to eat late at night. There
(45:53):
are protein bars in there, as well as apples and
bottles of water. It keeps me from going downstairs and
eating four thousand calories because I can't sleep and I'm
upset about something that happened that day. Disha also spends
about five days a week exercising for ninety minutes. She
(46:15):
has a special playlist of upbeat music that she listens
to when she exercises, and only when she exercises, like
Let's say she gets a craving to listen to those
songs at another time. It happens a lot, in fact,
but Disha doesn't do it. She won't let herself. So
(46:35):
anything I can do to spice it up and make
it different. And because it is easy to stop feeling motivated,
especially when you're basically at your goal, but I do
find new ways to constantly motivate myself and make it fun.
It has to be fun. The measures that successful dieters take,
(47:00):
other words, can take over their lives. This is the
part that's usually missed about the National Weight Control Registry. Sure,
these people have all lost large amounts of weight and
kept it off for many years, but what it has
taken to get them there is totally unreasonable. It just
(47:21):
doesn't seem possible for most people or even worth it.
And you always find a few people who are able
to lose a lot of weight. This is Glenn Geeser,
a professor at Arizona State University who's criticized the National
Weight Control Registry. Most people are unwilling to do what
it takes to get the weight loss that they would like,
(47:43):
things like lock your favorite snacks in a safe so
there's a huge gap between what people would like to
weigh and what is feasible. Glenn has actually done some
math to figure out how many dieters make it to
the National Weight Control Registry. In other words, lots of
(48:06):
people diet, how many lose at least thirty pounds and
keep it off for a year or more. About a
hundred and twenty five million Americans try to lose weight
each year, So the ten thousand people that are in
the National Weight Control Registry represent about one out of
every twelve thousand five US adults trying to lose weight.
(48:31):
As in, for every person in it, there are probably
twelve thousand, four hundred and people who didn't lose that
kind of weight or didn't keep the weight loss off.
That means registry participants aren't even the one percent, they
are the point zero zero eight. But the point is
(48:52):
is that the people who are in the National Weight
Control Registry are just a very very small drop in
in a big, big bucket of people. James Hill, the
registry is co founder who we talked to earlier, actually
sort of agrees with some of the criticism. This is
not for the faint of heart. If you're going to succeed,
(49:14):
You're going to have to put time and effort into
it for the foreseeable future. This idea, you know, it's
short of the American ideas go out and go on
a diet and then everything will be fine. Right, It
doesn't happen. Most people who lose weight regain it. The
hardest part, James says, is keeping it off. He has
(49:35):
responded to some of these critiques by starting a whole
new project. It's called the International Weight Control Registry, and
it launched last year. This new registry is tracking a
much wider group of people, including those who have not
been able to lose weight. The team is also trying
to reach a more diverse group of members. The National
(49:57):
Week Control Registry's typical member is four. You're fifty years
old and generally a white woman. I kept thinking about
how much people in the registry who have kept weight
loss off have had to diet and exercise. For some
of them, it became so all encompassing that they turned
(50:20):
it into a profession. They became dietitians or personal trainers,
and it seemed like it was worth it for them.
Many of the things they did probably did help make
them healthier, and they probably started thinking of themselves differently too,
as someone really fit with a lot of willpower and determination.
(50:42):
Like Dasha, I basically did something that I have been
able to do according to science, according to everything that
I've ever read, And in a way, Desha and the
others have new lives now, but that number on the
(51:06):
scale still rules their time, their energy, their interests, and
their identities. They're afraid of what will happen if they
stop dieting and exercising, because they might gain the weight back.
Even though they've gotten what they wanted, they still live
with a lot of fear. So maybe you're wondering why
(51:29):
diet anyway, The backlash against dieting is very much at
our doorstep. So I really don't like the word diet.
That word, to me is just so negative and it's just,
you know, the thoughts that come with that word are
like deprivations, starving and just not getting to have anything good.
And in our next episode will look at how diet
(51:53):
has become sort of a four letter word but hasn't
really gone away a some of the people in the
biggest rush away from dieting, they actually run weight loss companies.
It's different it's something that I can actually live with.
It's I wouldn't even call it a diet losing. It
(52:14):
is written and reported by me Ema Court and edited
by Kristin B. Brown. Magnus Hendrickson is our senior producer,
Stacy Wong our associate producer, and Blake Maples is our
audio engineer. Our theme was composed and performed by Hannis Brown.
Thanks to Francesco Leavie and Tim Annette. Be sure to
(52:35):
subscribe to Prognosis if you haven't already, and if you
like our show, please leave us a review that helps
others find out about it. Thanks for listening, See you
next time. Two
One of the first things I noticed when I walk
into Pennington Biomedical Research Center is a giant stained glass window.
It's filled with images of healthy living cast in rainbow colors.
You see there are two wheels here, and there is
a cyclist on on the top, and then there is
(00:22):
all kinds of fruits and vegetable. I mean, it's it's
quite a nice piece of art. The stained glass window
towers above a Pennington entryway. Brightly colored shards of glass
depict asparagus, bananas, peace, and a pineapple. The outline of
a runner cuts through the background, painted in shades of
(00:45):
orange and purple. And then there's a DNA DNA on
the right. There are blue and pink fish at the bottom,
canteloupe on the side. The longer I stare, the more
bowls of healthy living reveal themselves. But it's all about
what we do. I mean, you know health, genetics and biology,
(01:09):
and you have you have all the elements of nutrition,
you have the exercise, you have the d n A.
The whole thing makes the place feel like a temple
to nutrition, because it kind of is. Pennington is a
sprawling research center working to study obesity. Our tour guide
(01:30):
today is Eric Ravasan, a prominent scientist in the space
who is Associate executive director for Clinical Science at Pennington.
He's the one talking me through all of the stuff
in this very large stained glass window. Stained glass is
obviously more a feature of churches, but the religious symbolism
(01:53):
is sort of fitting. Really, this is a place that
treats weight loss as a sort of gospel. Pennington has
two acres of campus, including labs and research facilities, around
two hundred scientists and state of the art equipment, much
of it dedicated to unlocking the secrets to shedding pounds.
(02:19):
It's in Baton Rouge, Louisiana, and it feels like a
college campus minus the students. I've been on a journey
to get to the bottom of the science of weight loss,
and as our stained glass windows shows, weight loss is
something we all have lots of ideas about. Some of
(02:39):
those ideas are actually true, but they're all too often
not the whole truth. If anyone could help us sort
one from the other, I figured it would be the
people here. First, though, We're going to take a look around.
That's part of the way you test. Participants are like,
we're walking up to the fourth floor. Yeah, we got.
(03:03):
Our first stop is to check out some fairly innoxious
looking medical machinery. It's big and gray and looks almost
like a bed. And is this the machine beginning now?
It started already. Radiation is on right now because you
can see the lagser on saying in a radiation is
that this equipment can actually tell you how much of
(03:24):
your body is fat, and how much of it is muscle,
and how much is bone. I want to call it
a nightmare machine. It's the scan no one wants to
see of themselves. But what this equipment really measures is
body composition. And the total of this person here is
(03:46):
thirty points six of the body is fat. We often
talk about the number on the scale like it's the
only thing that matters, but this is a good reminder
that wheat isn't every thing. That's why weight loss researchers
use tools like these body composition machines. And a big
(04:08):
finding they've had is that people vary a lot. People's
bodies are different, really really different, and that's actually at
the root of a lot of the findings they've made
here at Pennington. But first, back to the tour, We
check out a big area known as a metabolic kitchen,
(04:31):
where calorically precise foods are prepared for studies, and we
walk by spaces that look like hospital rooms. They're also
used for research. Eventually we get to the craziest stop
on the tour. We step into a hall that looks
into small furnished rooms to seek a curtain and the
(04:58):
bed and you have everything could be happy, and there's Stevie.
They look like really sad studio apartments. Even though there's furniture,
the rooms are sterile looking. There aren't exactly many homey touches.
That's because they're actually rooms where scientific research happens. They're
(05:20):
called metabolic chambers, and they measure metabolism. Like the name suggests,
these sad little rooms are designed to measure how many
calories the person inside is burning. People stay in them
for a good chunk of time, thus all the furniture.
Eric also points out that they have windows. We fast
(05:41):
the food and uh and you know through here outside
of the metabolic chambers, in the hallway where we're standing,
a bunch of pipes and scientific instruments line the walls.
It kind of looks like a boiler room or something.
This equipment track everything going on in the little rooms.
(06:03):
Cool right, Maybe a little creepy too. Eric tells me
that there are only about thirty metabolic chambers in the
world thirty, and Pennington is home to four of them.
When we arrive, there's actually a woman in one of
the rooms already. She's sitting on the bed. It looks
(06:25):
like she's scrolling on her phone. Maybe in a little
while she'll go use the adjoining toilet. Watching the stranger
live her life in a little box while equipment measures
what's going on inside her body is pretty weird, Even
if it is for science. The whole thing feels a
(06:46):
bit dystopian. It makes me think of like a lab
rate in a maze or something. Now she probably can't
see this, but a computer screen right behind Eric and
I actually shows how many calories she's burning on a
minute by minute basis. A chart shows us how that
(07:06):
rate is changing over time. Eric tells me that while
the woman slept, she burned just under a calorie a minute.
Then I would say she got up here. He's saying
that because we can see on the screen that at
this point her metabolism jumps. People tend to burn more
(07:28):
calories as they become more active. She went to brush
your teeth, you know, metabolious me here goes to three
calories a minute. Then you can see and at the
end of the day we summarize how many calories she
has doing. The real work of the metabolic chamber is
happening silently in the air, because the chamber is actually
(07:50):
tracking how much oxygen the woman in the room is
taking in and how much carbon dioxide she's breathing out.
I Well, both oxygen and carbon dioxide are involved in
the process of converting food into usable energy. A little
math and toda, you have calories burned. This is all
(08:16):
part of metabolism, something we usually think about only in
terms of how fast we gain or lose weight, and
that's definitely part of it, but metabolism is also what
keeps us alive and kicking, something that we should celebrate
not blame. You know how people are always talking about
(08:41):
calories in calories out. A metabolic chamber is a very
precise way of calculating the calories out. Part. Technology like
this is really important at places like Pennington where researchers
are digging into the secrets of weight loss. And by
the way, some of what they've learned, is that calories in,
(09:05):
calories out is not the whole story, not by a
long shot. I asked Eric what to make of the
numbers the metabolic chamber is spitting out? Would another person
burn three calories a minute doing the same things as
the woman in the room just now? Like? Did I
burn that much getting ready this morning? That seems like
(09:28):
really interesting and even important data to have about yourself.
If any given way, sex page, and body composition, you
have large variability in between people. Metabolism differs a lot
by person. In other words, Eric couldn't really say if
I or another person would burn as many calories a
(09:50):
minute as the woman in the room. But he tells
me about some research he did way back in the eighties.
We measured people like in the chambers, re measured them
five years later and looked at the relationship between the
metabolism and the weight gain. They gain a lot of weight,
and we found that a low metabolity create is a
(10:12):
risk factor for weight game, otherwise known as I have
a slow metabolism. People love to say I'm gaining weight
just because I have a slow metabolism. But when we
say that, do we really know it for sure. No, no,
that you have to measure it. You have to get
into one of the sad little rooms. Metabolism isn't a
(10:34):
straight line. It can change over your lifetime, including as
you age and when you lose weight. Researchers have learned
more about that in recent years, and it may help
explain why dieters overwhelmingly regain weight over time. We'll get
more into this later. We walk by another suite of
(10:58):
rooms with a tread mill and stationary bike. Researchers use
these to push people to their exercise limits. It's kind
of like a stress test done by a cardiologist, except
even more intense. Nearby, a person is actually getting biopsies
taken of her fat and muscle. I watched the lab
(11:21):
tech sitting at her microscope work on a sample. There
are actual fat and muscle cells in front of her.
Is there anything you can't measure here? When it comes
to UM two, obesti, diabetes and cardiovascular disease. I think
we have it all. One of my co league used
(11:44):
to say, it's like toys are us for a kid? Uh,
you know, it's toys are us for a scientist? So yeah,
you're probably realizing by now that this is a place
with incredible resources fort etting weight loss. And the thing
about weight loss is that we all kind of think
(12:04):
we know the basics. Losing weight is about eating fewer
calories than you burn calories in calories out right. In
this episode, I'm going to get to the bottom of
what we actually know the science of weight loss. How
it's actually a lot more complicated than that simple formula.
(12:27):
And we're going to try to figure out why, why
it's so complicated, and why despite that the simple formula
of calories in calories out keeps getting repeated anyway, not
just by your neighbor or uncle, but by doctors and scientists.
(12:48):
To do that, we'll start this mecca of weight loss,
but we'll go beyond its walls too. I'm Bloomberg News
health reporter Emma Court and from the Prognosis podcast. This
is Losing It. Imagine that you're at the doctor's office
(13:21):
and they tell you to step onto the scale, which
they invariably do visit after visit. That number is measuring
not just your bone, muscle, and fat, but also possibly
your lunch from earlier, your shirt and pants, maybe some
p You can't talk about weight loss without first, making
(13:43):
sense of weight itself. And what doctors and scientists are
concerned about is not your clothing or undigested chopped salad,
or even your bone and muscle. They're worried about fat,
and specifically a person having too much. So how does
(14:03):
a person get more body fat? That comes back to calories,
which we went deep on in our first episode. Remember,
calories aren't just align on a nutrition label. They are
source of energy for your body. Calories are the gas
in your cars fuel tank. Every day we're taking from
(14:24):
that tank because we gotta um, we gotta move. This
is Leanne Redman. She's an expert in physiology or how
human bodies function, and she works for Pennington. We've got
a digest food we think we just function to every day,
we've got energy going out of the tank. So every
day we have to replenish the energy going into the
(14:45):
tank to keep your weight the same. Ideally, you'd be
eating around the same number of calories that you burn.
Lean says, there's a little wiggle room here of about
a few hundred calories a day. But eat too many
calories for too long and that energy has to go somewhere.
(15:06):
It gets stored in the adipose tissue in the body fat,
and then we gain weight gain atiposity of a time,
and that eventually leads to obesity. In other words, fat
is another store of energy. We've demonized it the same
way we've demonized metabolism, but it actually serves this and
other really important functions. Still, extra fat can put a
(15:31):
lot of stress on your body. That's why doctors and
scientists worry about people having too much fat. A quick
note about language here. We will be talking a lot
about weight in this episode, in particular because of the
stigma and bias about this subject. There are different schools
(15:53):
of thought about how to talk about it. The fat
Acceptance movement embraces the term fat. Some doctors and scientists
favor saying person with obesity. I will talk about it
as much as possible the way people do themselves. I
have tried to avoid the terms overweight and obese, though
(16:15):
I have had to use them at times for clarity's sake,
times like now. Obesity is usually defined as when a
person's body mass index is over thirty. As a refresher
b M I equals weight divided by height squared. The
number is supposed to be a proxy for body fat.
(16:37):
But as the formula I just rattled off makes clear,
b M I doesn't actually rely on your body's measured
fat composition, just weight and height, and b M I
is what's overwhelmingly used to talk about weight, like when
rates of obesity in the US began increasing in the eighties.
(16:59):
Around this time, government stats show that nearly six of
American adults were considered too heavy increase from an earlier period.
That judgment was made using b M I, and it
keeps being made using b M I, and it tells
us that Americans keep getting heavier. Today, nearly three quarters
(17:24):
of adults are considered by the government to have higher
than normal weights. So again, calories matter because extra calories
can turn into fat. It's that saying that you've heard
so many times before, calories in calories out. This is
also something we've known for a long time. When you
(17:46):
eat just enough food to supply the energy you need,
your white stays the same. But when you eat more
than you burn up an energy, the rest is starred
as fact. So is it really just that simple calories
in calories out. The answer is yes, sort of ish,
(18:08):
not exactly. Calories in calories out is true, but it's
also not true. If you're lost right now, that's okay.
I promise it will all make sense by the end
of the episode. Remember, we came here to Pennington for
a reason. We wanted to sort out when it comes
to wait, what's fact, what's fiction, and what's still a mystery?
(18:33):
So how do we know that calories in calories out works?
When you walked through this thing that looked like a
medical ward to get to the metabolic chambers. This is
Owen Carmichael. He runs the Biomedical Imaging Center at Pennington.
So basically some of the fancy machines we've been looking at,
(18:55):
we've actually had studies where people live there and they
sleep in the hospital like beds. They're living in a
what looks like a hospital where they're interacting with a
lot of nurses and um that they do not have
a refrigerator that they have free access to. They cannot
order up snacks. They're in a controlled environment. They're being
(19:18):
given calorically precise meals. The sprawling Pennington Gym is nearby.
For some people, this might sound like the ideal conditions
to diet, the v I P diet life, and that's
exactly what the scientists intended for other people. Of course,
this might sound more like torture, but anyway, Pennington researchers
(19:43):
have found that they really, honest to goodness, lose weight,
and they lose fat, not muscle, So it's good weight loss.
People lose weight, at least they do when they spend
that whole time at Pennington. But you can't do that
for a really long time. Study participants have lives to
(20:05):
get back to, and it's exactly when they do that
step outside the boundaries of Pennington out into the real world,
that the trouble begins. I think it's very difficult to
really wrap your head around how seven this thing we
call the obesogenic environment is that scientists speak for the
(20:28):
kinds of unhealthy environments that surround us every day. The
Danish cart on the corner by your office, not having
a grocery store in your neighborhood, living somewhere with lots
of cars but no sidewalks. If you're lucky enough to
have enough to eat, the world can sometimes seem like
it's shoving a plate of fries down your throat. Seven.
(20:53):
And while you have some limited ability to decline, that
metaphorical plate of fries. Not everything is under your control.
We've all experienced this. I even saw it when I
was visiting Pennington for this episode. Here I was speaking
with scientists all day long, talking about the importance of
(21:16):
healthy eating and portion control and cooking food at home.
And meanwhile, I'm staying in a hotel and eating literally
all of my meals out. And did I mention that
Pennington is based in Louisiana A fantastic lace into like
a little peopood. This is a place essentially a full boy.
(21:40):
I like my overflowing with brad shrimp. That thing is
as big as you. Everywhere I went, I kept ordering
food without realizing that it was all deep fried. I
was at lunch one day with a bariatric surgeon who
works at Pennington, and the waiter rattled off a long
list of very fried recommendations. Again, my dining companion here
(22:06):
does weight loss surgery for a living. It was kind
of surreal. When we finished up, they actually brought us
a plate of cotton candy, which we had not ordered
for free. And it's not just the environment around us
that's making things difficult. It can be us too. Here's
(22:27):
leanne again, So it is definitely ultimately about this imbalancing calories.
But it's very, very complicated, right because there are so
many factors that determine what we eat when we you know,
where we're craving something, whether we're full, whether we're hungry
or not. And then on the other side, when you
(22:49):
reduce people's calories, they're like, oh, I'm eating less, so
I'm gonna like, I can, you know, move less? Right,
So they start conserving calories and maybe not as physically active.
The same is true when people are exercising more, they
need more calories, and when people start eating less, our
bodies respond to that. Remember that calories aren't some inconvenient
(23:13):
aspect of oreos their energy. When you have less energy
coming in, your metabolism slows down. That actually makes sense
if you think about it. Your body is now smaller,
so running it moving it around that takes less energy,
(23:35):
kind of like how smaller cars can be more fuel efficient.
But studies of contestants on the TV show The Biggest
Loser have found that metabolism can drop even more than
you would expect. Pennington researchers were actually involved in those studies,
including Eric Ravesson, who took us on the tour earlier,
(23:56):
but we we measured all the people from this season eleven.
He was quite a riot to go to the ranch
outside in California. There's a name for this phenomenon of
metabolism slowing more than expected after weight loss. It's called
metabolic adaptation. Scientists have also found that after weight loss,
(24:20):
hormones that regulate hunger and weight can get disrupted for
long periods of time. These hormonal disruptions and metabolic adaptation
could help explain why so many people regain weight after dieting.
In other words, a person goes on a diet, they
(24:43):
regain the weight later, and people assume it's the dieter's fault. Right,
It seems pretty logical. After all, they say, oh, she
stopped eating as many salads, or that he stopped going
to the gym as much, and maybe they say even
more unkind things than that. But here's the thing. Scientific
(25:08):
research tells us that there may actually be a biological
reason for those things happening. That a dieter could be
getting really hungry because of hormonal disruptions, that their body
might actually be burning way fewer calories after weight loss.
When I first learned about this, It kind of blew
(25:29):
my mind because there seems to be a scientific explanation
for why so many dieters regain weight over time. Your
body is actively fighting back, and that actually makes sense
if you think about evolution, because bodies need energy to live.
An energy used to be a lot harder to come by,
(25:51):
so at the end of the day, it does come
down to the energy imbalance, the intake, and the expenditure.
You have to be out of balance in order to
change weight. But it's all of these other physiological signals
that are driving the intake and the expenditure that we
need to understand better in order to be able to
achieve weight loss for everyone. We're simplifying the science here,
(26:14):
but needless to say, these are complicated things to study,
and it helps to have a dedicated research facility like
Pennington with all its bells and whistles focused on it.
Remember how earlier I said that Pennington feels like a
college campus. It's actually officially part of Louisiana State University,
(26:37):
which is also in Baton Rouge a few miles away.
Back in the nineteen eighties, the head of l s
U got the billionaire oilman Claude Bernard Pennington to commit
hundred and twenty five million dollars to start a nutrition
research center. Over the decades since, the center has been
(26:58):
involved in some of the most cordant research done about
weight and weight related conditions at the Pennington Biomedical Research
Center Biomedical Research Center. Researchers from the Pennington Biomedical Research
Center in Louisiana found Pennington Biomedical Pennington Biomedical Research Center
Pennington Biomedical Research Center in Baton Rouge, So to summarize, studies,
(27:20):
including ones done at Pennington, have shown that when people
eat less, they lose weight. Calories matter pretty self explanatory,
but as we just talked about, calories also aren't the
full story. There's this big gulf between what happens in
research studies at places like Pennington with its gadgets and gizmos,
(27:44):
and the real world. And scientists are also still learning
more about how your body seems to fend off long
term weight loss. So what is all this add up to.
It means that weight loss is more complicated than advertised,
a lot more complicated. It also means that losing weight
(28:06):
isn't fully in a person's control, even though that's how
we tend to talk about it. Reasons like this are
why scientists and doctors have started to call obesity a
disease the same way that diabetes and cancer are diseases.
And if obesity is a disease, dieting takes on even
(28:28):
more importance. It's not just a way to lose weight,
but also a form of medical treatment. And if diets
are medicine, surely we know what the best diet is
for a person. Right the Great diet debate, low carb
or low fat, high fat diets actually may be superior
(28:51):
to low fat diet. In the low carbohydrate groups, they
lost about two and a half to five pounds more
than those in the low fat diet crew. Carbohydrates are
the single most important thing you can eat for health
and weight loss. And you're thinking, right now, Dr Hyman,
have you gotten nuts? Practically each decade has had a
(29:13):
new dietary villain. First fat was bad, and then carbs
were bad. Now I think maybe they're both still bad,
but so is sugar too. Right where did we land
on all that? I'll answer that in a minute. First though,
back to Pennington. As I spoke with scientists at the Center,
(29:36):
I kept feeling like I was going in circles. They
would tell me how complicated weight loss turns out to be.
Now there's so much variability between people, and not just
with burning calories, but in terms of how easily people
lose or gain weight. Now there's still so much scientists
are learning. And then I would ask them, well, what
(29:58):
should people do if they want lose weight? And they
would say, diet, eat fewer calories. And so I'm going
to get the person to write down everything that they
eat and drink for the next five days, and we're
going to look at where the excess calories are coming from,
and we're going to start there. I told Leanne how
confused I was by this. How can it be more
(30:20):
complicated than calories in calories out? But also that calories
in calories out is the answer. And then leon tells
me something that just might haunt me forever. Remember our
metabolic chamber from earlier, the sad little rooms. She and
her colleagues at Pennington did a study where they put
(30:40):
people in there, and the scientists actually over fed these
people on purpose. They gave them more calories than needed.
They were trying to make them gain weight, and this
is what they learned. Some people will burn majority of
the excess calories that they've eaten, and they're the people
(31:01):
that will retaine their weight. Some people will burn, will
burn those extras, some people will burn none. And Leanne
says they've also found that the opposite is true. When
you give people less to eat, some people lose weight
immediately and others just don't. In other words, it's calories in,
(31:25):
calories out, but only for some people. So what I'm
taking away from all this is, if you are a
person who wants to lose weight, we don't have great
information for you dieting calories in, calories out best. We
have another way of putting all this is other people
(31:47):
get to eat as many honey buns from the vending
machine as they want and just burn it all off.
But you don't. By the way, there are other options
for weight loss besides diet, like medication and surgery, but
they're used a lot less. I was struck by what
(32:08):
Leanne said. Though, for all the new fingled machinery and
fancy gadgets we toured earlier, the answer is that we
still don't have an answer. Even though dieting doesn't work
in a long term way for many people, dieting is
still the best we've got, and yet the dogma is
(32:28):
still why don't you just diet? No uncertainty, no caveats,
none of the nuance we uncovered here at Pennington. I
asked Leanne about the uncertainty about the lack of sufficient
answers a couple of times, until finally she said this.
You know, we've spent billions of dollars trying to understand
(32:53):
obesity and white management and how it a fixed people
and how we can help people, and it just seems
like it's all going to a black hole because you know,
even with that huge investment, we have no answers. You
just heard Leanne Redman, an expert in physiology at Pennington,
(33:16):
saying that despite all the money that's been invested in
weight loss, not to mention all the fancy equipment and
scientists who have spent their careers working on the subject,
we have no answers. We have no answers. In fact,
that's exactly why we keep coming back to diets. They're
(33:37):
not the answer, but they are the closest we've gotten
to an answer. Then again, there are a lot of
diets out there. The South Beach diet low fat whole thirty,
So so many diets, which ones actually work the best?
(33:58):
I put the question to Christopher Gardner, a nutrition scientist
at Stanford. This is a super depressing answer that nothing
works because we haven't resolved the obesity epidemic. I know,
this is getting really frustrating, right. One of the things
that we do know is that there isn't one diet
for everyone. So people who claim that it's my diet
(34:21):
or it's the Paleo or the Kido or the something else,
I just it's not true. Let's say I invented a diet,
it's named after me, obviously, and I go around telling everyone, look,
this is the diet that's going to finally make you
lose weight. Basically, what I'm saying is I tried Emma's
(34:43):
diet and it was awesome, and everybody should try Emma's diet.
And what I do as a scientist is I get
a hundred people and I signed fifty two Emma's diet
and fifty to the other diet. And I have to
see that, yeah, way more people on diet A work
than DIETETE and you really doesn't happen. And so what
we found is that there isn't one diet for everyone.
(35:05):
The big problem is keeping it up. I don't eat
carbs until I'm craving them so much that I give in.
I don't eat out until it starts crushing my social life.
All diets have at least this in common. What's the
best diet to be on? It's the one you can maintain.
In other words, if you can keep up a low
(35:26):
carb diet, power to you, same for a low fat diet.
But how do you know at the outset which one
is going to work for you. That's where lots of
scientists across this field are now channeling their efforts. The
consensus now is that diets should be individually matched a
person based on different factors about them, kind of like dating.
(35:51):
My diet biography might say I'm a court journalist, sits
at a desk all day, works out a few days
a week, loves her kale salads, sweet tooth. But there's
still a lot missing from that description, things that I
couldn't tell you, and even Pennington scientists can't use right
now to match me to a diet, Like what's going
(36:15):
on in my gut microbiome that's the collection of bacteria
involved in digestion and metabolism. What about my genetics? Those
are factors that could help you match a person better
to specific diet or what's known as precision health. But
it's very hard to find the genetics or the metabolism
(36:39):
so far that would point you to one diet or another.
We're not there yet, not by a long shot. Scientists
are trying to figure it out though. In fact, the
National Institutes of Health is just starting to fund a
study about this. So again, low fat diets aren't the
(36:59):
best diet it for everyone. Neither is low carb diets
may have to be tailored to the individual. All the
research on dieting and weight loss over the years has
brought scientists to this conclusion. I know, I know. But
the thing is, for all we don't know about weight loss,
(37:21):
there are some things we do know. We actually know
a fair amount about the people who lose weight and
keep it off, what they do, and what it takes.
There was a sense of it's pretty hopeless, uh and nobody,
nobody really succeeds in weight management. If you're a based
you're just out of luck because you know there's not
(37:44):
much you can do about it. People try to diet
but it doesn't work. That was James Hill, who is
Chair of Nutrition Sciences at the University of Alabama at Birmingham.
He's talking about how in the late nineteen eighties rates
of obesity began rising very suddenly. Remember we talked about
this earlier, how those rates had been stable beforehand, but
(38:08):
they've risen and risen until today. And again, as all
this is happening, people are feeling pretty hopeless about losing weight.
So James and his colleague Rena Wayne, who is a
professor at Brown University's Medical School, decided to start tracking
successful dieters. They created the National Weight Control Registry, which
(38:32):
people can join if they have lost at least thirty
pounds and kept it off for at least a year.
There are more than ten thousand members today. James says
that the Registry was supposed to answer a key question,
what does it take to lose weight long term? And
the Registry has actually provided some answers, as evidenced by
(38:57):
thirty scientific papers James and his colleague have written about it.
That's right, we know what it takes to lose weight
long term. You just have to diet and exercise and
prioritize it every single day and worked really hard forever.
(39:22):
So one of the things I always tell people that
we've learned from the National Wake Control registreet it takes
a lot of conscious effort for these people to stay successful.
So it's not the case that they lost weight and
then they went back to living your lives and didn't
think about it. You might remember from our last episode
that this is a diet myth the South Beach Diet
(39:44):
helped spread in the two thousands. They prioritize their weight
very very highly. Of all the people who diet, and
there are many, very few of them actually end up
joining the Red Distry. We'll talk about that more in
a bit. First, though, here's what we know about people
(40:07):
in the National Weight Control Registry. Most of them eat
a relatively low fat diet, but some people do the
low carb thing too. Again, the specific diet doesn't seem
to matter that these folks. Diet seems to matter more
than what kind of diet. Most of them spend probably
(40:29):
more time than the average person thinking about their diet
during the dash, thinking about what they eat, keeping track.
A lot of them keep diet diaries, so they pay
attention to the food they eat. National Weight Control Registry
members weigh themselves every day. They track what they eat
(40:49):
and how much physical activity they get. They're also all
exercising about an hour a day. Jane Fonda and eighties
exercise icon wanted everyone to feel the burdens, not just
National Weight Control Registry participants. If you're thinking that an
(41:12):
hour a day is a lot of exercise, you're right.
The US government recommends a few hours of exercise a week,
and most adults aren't even doing that. I spoke with
five members of the National Weight Control Registry for this
episode and heard similar things for starters. Nearly all of
(41:35):
them exercise intensely most days, and a lot have adopted
some pretty extreme habits to keep their weight off over time.
One guy I spoke with, his name is Marcos Goodman,
told me that he had lost sixty five pounds eight
years ago. To keep it off, he eats the same
(41:56):
five or six meals every day so he doesn't have
attract different foods, like for breakfast, oatmeal with flax seed
and sesame seeds, a banana and some non fat milk,
a stew for lunch made of either sardines or chicken,
and then an evening meal of soybeans. Another woman I
(42:18):
spoke to, Susan Pierced Thompson, lost sixty pounds eighteen years
ago and then since then maintained her weight by cutting
out flour and sugar completely. Susan ended up starting her
own weight loss program based on those ideas. But the
thing that struck me the most was the mental and
(42:39):
emotional energy all these people spent on simply maintaining the
weight that they had lost. It just became this big
part of their lives. For some of them, their lives
even sort of seemed to revolve around this one thing.
No one ever says, this is going to be really painful.
(43:00):
You better get ready because you are going to suffer.
No one ever says that, and I did suffer tremendously.
This is Desha Gill, a fifty six year old stay
at home mom who lives in Dallas, Texas. She's talking
about the process of losing weight what it was like
(43:20):
for her. I don't know if you've ever tried to
sleep when you're really really hungry, not just wanting to eat,
but truly feeling like you're starved. That's how I had
to feel every night. Disia says she has struggled her
weight since she was eleven years old. She told me
(43:40):
that she started off binging on candy bars at summer camp.
I was always very interested in health and longevity, and
I wanted to be active and athletic, and but who
I felt like and what I looked like could not
have been anymore opposite. And I found it humiliating and
(44:04):
embarrassing to look at myself and for people to see
how I would. I was repulsed and so ashamed all
the time, all the time. Desha says she has probably
read hundreds of weight lost books. She has tried weight watchers,
(44:25):
Jenny Craig over eaters anonymous, she got a lap band,
a surgical procedure that constricts the stomach. She even tried hypnosis,
none of it worked. She also says she experienced health
issues that seemed related to her weight, like fatty liver disease,
and asthma. Desha knew she needed to make a major change.
(44:50):
She begins shifting how she eats and ends up losing
a hundred and ten pounds, But she's also raising suns,
which means lots of tempting foods in the house. I
did research and found these food safe that have timers
on them, and so I bought some food safe so
(45:12):
that I could put the food that I had trouble
controlling myself with those food staves, so that my son
and this could get them, or if I wanted to
treat at some point, I could time it so that
I couldn't get into the food safe until I said
that I could. Disha still uses those food saves. They're
(45:32):
made of plastic and have a dial at the top.
She sets them to unlock over periods of hours or days,
so she can't eat, say, candy or chocolate whenever she wants.
She also keeps a fridge near her bedroom in case
she gets the urge to eat late at night. There
(45:53):
are protein bars in there, as well as apples and
bottles of water. It keeps me from going downstairs and
eating four thousand calories because I can't sleep and I'm
upset about something that happened that day. Disha also spends
about five days a week exercising for ninety minutes. She
(46:15):
has a special playlist of upbeat music that she listens
to when she exercises, and only when she exercises, like
Let's say she gets a craving to listen to those
songs at another time. It happens a lot, in fact,
but Disha doesn't do it. She won't let herself. So
(46:35):
anything I can do to spice it up and make
it different. And because it is easy to stop feeling motivated,
especially when you're basically at your goal, but I do
find new ways to constantly motivate myself and make it fun.
It has to be fun. The measures that successful dieters take,
(47:00):
other words, can take over their lives. This is the
part that's usually missed about the National Weight Control Registry. Sure,
these people have all lost large amounts of weight and
kept it off for many years, but what it has
taken to get them there is totally unreasonable. It just
(47:21):
doesn't seem possible for most people or even worth it.
And you always find a few people who are able
to lose a lot of weight. This is Glenn Geeser,
a professor at Arizona State University who's criticized the National
Weight Control Registry. Most people are unwilling to do what
it takes to get the weight loss that they would like,
(47:43):
things like lock your favorite snacks in a safe so
there's a huge gap between what people would like to
weigh and what is feasible. Glenn has actually done some
math to figure out how many dieters make it to
the National Weight Control Registry. In other words, lots of
(48:06):
people diet, how many lose at least thirty pounds and
keep it off for a year or more. About a
hundred and twenty five million Americans try to lose weight
each year, So the ten thousand people that are in
the National Weight Control Registry represent about one out of
every twelve thousand five US adults trying to lose weight.
(48:31):
As in, for every person in it, there are probably
twelve thousand, four hundred and people who didn't lose that
kind of weight or didn't keep the weight loss off.
That means registry participants aren't even the one percent, they
are the point zero zero eight. But the point is
(48:52):
is that the people who are in the National Weight
Control Registry are just a very very small drop in
in a big, big bucket of people. James Hill, the
registry is co founder who we talked to earlier, actually
sort of agrees with some of the criticism. This is
not for the faint of heart. If you're going to succeed,
(49:14):
You're going to have to put time and effort into
it for the foreseeable future. This idea, you know, it's
short of the American ideas go out and go on
a diet and then everything will be fine. Right, It
doesn't happen. Most people who lose weight regain it. The
hardest part, James says, is keeping it off. He has
(49:35):
responded to some of these critiques by starting a whole
new project. It's called the International Weight Control Registry, and
it launched last year. This new registry is tracking a
much wider group of people, including those who have not
been able to lose weight. The team is also trying
to reach a more diverse group of members. The National
(49:57):
Week Control Registry's typical member is four. You're fifty years
old and generally a white woman. I kept thinking about
how much people in the registry who have kept weight
loss off have had to diet and exercise. For some
of them, it became so all encompassing that they turned
(50:20):
it into a profession. They became dietitians or personal trainers,
and it seemed like it was worth it for them.
Many of the things they did probably did help make
them healthier, and they probably started thinking of themselves differently too,
as someone really fit with a lot of willpower and determination.
(50:42):
Like Dasha, I basically did something that I have been
able to do according to science, according to everything that
I've ever read, And in a way, Desha and the
others have new lives now, but that number on the
(51:06):
scale still rules their time, their energy, their interests, and
their identities. They're afraid of what will happen if they
stop dieting and exercising, because they might gain the weight back.
Even though they've gotten what they wanted, they still live
with a lot of fear. So maybe you're wondering why
(51:29):
diet anyway, The backlash against dieting is very much at
our doorstep. So I really don't like the word diet.
That word, to me is just so negative and it's just,
you know, the thoughts that come with that word are
like deprivations, starving and just not getting to have anything good.
And in our next episode will look at how diet
(51:53):
has become sort of a four letter word but hasn't
really gone away a some of the people in the
biggest rush away from dieting, they actually run weight loss companies.
It's different it's something that I can actually live with.
It's I wouldn't even call it a diet losing. It
(52:14):
is written and reported by me Ema Court and edited
by Kristin B. Brown. Magnus Hendrickson is our senior producer,
Stacy Wong our associate producer, and Blake Maples is our
audio engineer. Our theme was composed and performed by Hannis Brown.
Thanks to Francesco Leavie and Tim Annette. Be sure to
(52:35):
subscribe to Prognosis if you haven't already, and if you
like our show, please leave us a review that helps
others find out about it. Thanks for listening, See you
next time. Two
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