June 23, 2026 • 33 mins
Intermittent fasting has become a big wellness trend online , but does the science actually support the hype?
In this episode of Health vs Hype, host Trace Dominguez digs into the medical evidence behind intermittent fasting with obesity medicine specialist Dr. Jen Schriever. Together, they break down the biggest claims surrounding fasting, including weight loss, insulin resistance, metabolic health, autophagy, mental clarity, longevity, and “metabolic reset.”
You’ll hear real experiences from intermittent fasting advocates Gin Stephens and Al Kavadlo, alongside expert analysis about what current research actually shows and where the evidence is still weak. Is intermittent fasting better than traditional calorie restriction? Can fasting improve blood sugar or help prevent disease? And who should avoid fasting altogether?
This episode explores:
- The science of intermittent fasting and weight loss
- Insulin resistance, blood sugar, and metabolic health
- Claims about autophagy, longevity, and cellular repair
- Mental clarity and cognitive benefits
- Risks for people with diabetes or eating disorders
- Intermittent fasting vs GLP-1 medications like Wegovy and Zepbound
- Why diet quality still matters more than eating windows
If you’ve ever wondered whether intermittent fasting is truly healthy, or just another overhyped wellness trend, this episode separates evidence from marketing.
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Speaker 1 (00:04):
Ruby.
Speaker 2 (00:07):
It breaks people out. Sometimes what you don't eat breakfast,
what you don't eat launch either. Are you insane? Are
you dye like? People cannot wrap their head around the
way that I eat.
Speaker 3 (00:18):
Diet is what you eat. Intermittent fasting is when you eat.
Speaker 4 (00:23):
I've had a patient claim that fasting was the only
way she could lose weight.
Speaker 1 (00:27):
Intermittent fasting might feel like the latest wellness grace, but
humans have actually been doing versions of it for thousands
of years, sometimes for religion, sometimes for survival, sometimes even
for politics and protests. But over the last couple of decades,
fasting has gone fully mainstream. Now it's all over TikTok,
(00:48):
YouTube and fitness culture, with people claiming it can help
you lose weight, boost your energy, improve your focus, and
optimize your health. The problem is intermittent fasting can mean
almost anything. Aside from your three square meals a day,
There's sixteen eight, where you fast for sixteen hours daily
and restrict your eating to an eight hour window. There's
(01:09):
omad one meal a day, alternate day fasting, five to
two fasting. That's five days of eating a typical diet
and two of eating a calorie restricted diet. There are
juice fasts. Basically everybody has their own version. So when
there are this many options, what actually counts as fasting?
Are we really just restricting calories? Is there something else
(01:30):
going on? And more importantly, is intermittent fasting good for
your health? Or is this another wellness trend getting way
ahead of the science. Clearly we have questions. Like I said,
it might just depend on who you ask. Alcavad Low,
an online fitness influencer and personal trainer, shapes his entire
life around intermittent fasting. He follows a version called OMAD
(01:52):
or one meal a Day.
Speaker 2 (01:54):
So it started by postponing breakfast, and then it became
skipping breakfast, and then it became skipping breakfast and launch
and for the most part, I eat one meal a day.
Speaker 1 (02:05):
And then there's Jen Stevens, a former elementary school teacher
who got so into intermittent fasting that she turned it
into a whole second career. She's written multiple best selling
books on the topic, built a massive online following, and
now hosts a podcast dedicated to the intermittent fasting lifestyle.
Speaker 3 (02:23):
I was on that yo yo. I was either gaining
or losing, and since I lost, the weight with intermittent
fasting over ten years ago. I am steady and it
just feels amazing.
Speaker 1 (02:35):
And of course, doctors know what's science and what's bunk.
People like doctor Jennifer Shreever, a family physician at Sanford
Health who specializes in obesity medicine and long term weight management.
She spends a lot of time separating what intermittent fasting
can do from what social media claims it can do.
Speaker 4 (02:53):
They think that intermittent fasting might optimize our health so
that they can live longer, or they're just looking for
that structured, easy to follow approach and they want to
work on their health and that seems the simplest way
to do it.
Speaker 1 (03:06):
Welcome back to Health Versus Hype with the American Medical Association.
I'm your host Trace Tominguez. Today we're talking about intermittent fasting.
What is it? Can skipping breakfast really improve your health?
What does intermittent fasting do to your body? Join me
as we find out whether intermittent fasting is all health
or just hype. For millions of people, intermittent fasting isn't
(03:44):
just a diet. It's become a lifestyle, and few people
embody that more than Jenn Stevens, who discovered intermittent fasting
while trying to lose weight after years of struggling with
traditional dieting. But while stories like hers have helped fuel
the trends explosive popularity online, doctors and researchers are still
working to understand exactly what fasting does inside the body.
(04:08):
I want to start by understanding why someone would want
to adhere to such a strict way of eating. For that,
let's hear from Jin.
Speaker 3 (04:17):
I have a background, probably like a lot of women
and men, in that I was always chasing the next
best diet plan, right, you know. The first time I
needed to do a diet, turned to calorie counting like
most people. But that didn't work. It wasn't sustainable. I
tried literally everything that came along. I was officially obese,
I weighed two hundred and ten pounds, and I was
(04:40):
sick of it. And so of course I heard about
intermittent fasting. A few people were talking about it, and
I tried it, and I have never stopped since. So
I've been doing intermittent fasting since August of twenty fourteen
without stopping, and for the first time in my entire life.
Speaker 1 (04:56):
I have not yoyod.
Speaker 3 (04:57):
I've been able to maintain after I lost eighty p
I've been able to maintain since I.
Speaker 1 (05:02):
Lost the weight.
Speaker 3 (05:03):
So it is completely different than anything else I ever did.
Speaker 1 (05:07):
So what is intermittent fasting for people who might not know.
Speaker 3 (05:11):
Well, it's basically when we intentionally have periods of time
when we choose to fast, and then we have periods
of time when we choose to eat in an eating window,
so we are either intentionally fasting or our eating window
is open and we are intentionally eating. It's basically a
boundary around the times that you're eating.
Speaker 1 (05:33):
Jin came to intermittent fasting to lose weight, but many
followers of this lifestyle have found their way to intermittent
fasting through wellness and fitness advice. Alcavadlo is an influencer
who focuses on exercise for men in their forties who
are looking for new ways to stay fit and healthy.
Speaker 2 (05:49):
Fitness and exercise was kind of my gateway into being
interested in nutrition. I got more into improving the quality
of the food I was eating and also starting to
pay more attention to the fasting aspect. It all happened
very naturally For me, it never really felt forced. It
never feels like I'm depriving myself. It never feels like
I'm starving myself. To be frank, I'm not super dogmatic
(06:13):
about it. If there's a day where I am absolutely famished,
I'll eat a snack in the middle of the day.
It's fine.
Speaker 1 (06:19):
I want to take a break here and talk about
hunger for a minute. It's more complicated than simply having
an empty stomach. People feel hunger because the body and
the brain are constantly working together to monitor our energy needs.
One of the biggest players is a hormone called grellin.
It's often nicknamed the hunger hormone. When your stomach has
(06:40):
been empty for a while, grellin levels rise and send
signals to the brain telling you it's time to eat.
But blood sugar levels, hormones, sleep, stress, emotions, habits, and
even smell can all influence hunger too. For example, if
you have a habit of always eating lunch at noon,
your body may start triggering hunger signals around that time,
(07:01):
whether you actually need calories or not. During fasting, people
often notice hunger comes in waves rather than increasing endlessly.
That's because hormones like Grellin rise and fall throughout the day,
and the body can gradually adapt to new eating patterns
over time. Al alluded to this a.
Speaker 2 (07:18):
Little Just try to wait a little longer to eat breakfast,
because most people wake up and immediately start eating. They're
not hungry. They do it because it's part of their routine.
And if you actually are hungry fifteen minutes after you
wake up, god bless eat. But sometimes people find out, Oh,
you know what, I drank a glass of water and
I didn't get hungry for a couple hours. And that's
(07:41):
sort of how it happened. Familiar, and I've been doing
that for a long time now.
Speaker 1 (07:45):
Jin shared something similar.
Speaker 3 (07:47):
The thing about hunger is, let's imagine you're not an
intermittent faster, You're just someone who eats typically.
Speaker 1 (07:53):
Yeah, do you have hunger in your day? Sometimes yes,
yeah you do. You have hunger.
Speaker 3 (08:00):
And then you eat and then it goes away, and
then later you're hungry, good, and then you eat and
then it goes away. For intermittent fasters, we have hunger too,
and then it goes away, It fades without eating, and
your body is like, all right, I guess I'll munch
on some stored fat for a while. So the thing
about hunger is once you understand it doesn't build and
(08:23):
build and build and build. When you're fast and clean,
it's not an emergency. You have a little wave of hunger,
you acknowledge it, you do something else, and then you're
not hungry anymore.
Speaker 1 (08:34):
And let's face it, for all of us, but especially
for people trying to lose weight, specifically, evolving diet information
and guidelines can feel confusing.
Speaker 3 (08:44):
You know, should you be vegan, should you be carnivore?
Speaker 4 (08:46):
You know?
Speaker 3 (08:47):
Or plants trying to kill you? I mean, you know,
I can talk about every single diet out there and
what they want you to avoid or what you're allowed
to have or not allowed to have, but we get
so confused. We don't even know what we're supposed to
be eating anymore. But the best part about intermittent fasting
is that it isn't a diet at all. Because diet
is what you eat. Intermittent fasting is when you eat.
(09:11):
So we're all eating a diet, whether it's the standard
American diet or your vegan or your carnivore, or you're
following the Mediterranean diet. You're eating some sort of diet,
but intermittent fasting is when, so it's definitely not a diet.
Like I never say I'm doing the intermittent fasting diet.
Speaker 1 (09:28):
I want to introduce our medical expert now, doctor Jennifer Shreever.
She's been a family physician and obesity medicine specialist for
more than twenty years. I played that clip from Jen
for her, and here's doctor Shreever's reaction to it.
Speaker 4 (09:42):
You know, nutrition is complex, and it kind of seems like,
I'm sure to the normal population that our nutrition advice
has changed a lot across the years. I mean low
carved and low fat. So that's very confusing.
Speaker 1 (09:56):
And she's saying that because it's when you eat, it's
not a diet.
Speaker 4 (10:00):
That seems like a strange way to represent that. I
guess it depends on how you think of the word diet.
I mean, historically, diet is something that helps you lose weight,
and if that's a claim for internet and fasting, I
guess I would classify it as a diet. We try
not to use the word diet because it just has
kind of a negative connotation and it's something that you
(10:21):
do temporarily, right, and maybe that's what she's trying to
say too.
Speaker 1 (10:27):
She definitely talks a lot more about how this is
a lifestyle change and diets are temporary and lifestyle is permanent.
Speaker 4 (10:36):
Yeah, And my practice treating patients for weight management, I'm
trying to create and help you improve your lifestyle in
a way that you feel good in the process, lose weight,
have more energy. I don't want to have a plan
that you graduate from or finish. This is something that
we might continually have to adjust and manage over time.
(10:59):
So I think even people on intermittent fasting are going
to find that they're going to have to adjust and
adapt something over time. So that's giving the sense that
this is a long term solution. Life happens, life changes.
Some of that's under control, a lot of it's not.
There's nothing that is the final answer.
Speaker 1 (11:19):
Yeah, So when someone starts doing intermittent fasting, what happens
to our bodies.
Speaker 4 (11:25):
So what happens is your body will start to shift
from burning blood sugar or glucose to using your stored energy,
so you're fatty tissue during those fasting periods. During your
fed state, you'll probably return to using more sugar. Often also,
as one starts intermittent fasting depending on how they approach it,
(11:47):
but many will have less calorie intake. A person might
cut out that meal and not replace that nutrition later
in the day, so then you're just reducing your caloric
intake and that can contribute to some earth onset of
some initial weight loss, so then that makes you feel successful.
So by fasting, you know, one might have insulin resistance,
(12:08):
So that means that typically with having extra fatty tissue
around that doesn't recognize the insulin you're making, and so
if your blood sugar is not well managed and creeping up,
your body is going to make more insulin because it's
not recognizing that signal that that insulin is there. The
disadvantage to that is insulin wants to store calories, so
it's not managing your blood sugar as well because your
(12:29):
body isn't recognizing but it's still doing its job of
storing calories.
Speaker 1 (12:33):
Let me see if I can explain this a little more. Normally,
after you eat, your body releases insulin to help move
sugar from the blood into your cells so it can
be used for energy. But with insulin resistance, the cells
stop responding to the insulin efficiently, so the sugar stays
in the bloodstream longer to compensate, the pancreas pumps out
(12:56):
more insulin, and then over time, consistently elevated blood sugar
can lead to pre diabetes or type two diabetes and
increase the risk of things like heart disease, nerve damage,
and kidney problems. So creeping up basically means blood sugar
levels are gradually rising beyond what the body can comfortably regulate.
Speaker 4 (13:16):
So if internet and fasting has been shown to reduce
insulin levels and that's their intention, then you might be
storing less of your calories in fat. So that happens
pretty quickly as far as early in the fasting states,
at least as far as what evidence is currently leaning towards.
(13:36):
But does that lead to actual blood sugar control and
improved A one CS is yet to be seen.
Speaker 1 (13:42):
More research is needed. As I like to say, yeah,
and just so we all understand, A one C is
a blood test that measures your average blood sugar levels
looking back over the past two to three months. When
researchers talk about whether intermittent fasting improves A one C,
they're asking whether it meaningfully improves long term blood sugar control,
(14:02):
not just short term changes during the fast But I'm
really curious if intermittent fasting is just a different way
to restrict calories than your average diet, or if something
special is taking place in the body during intermittent fasting.
Speaker 4 (14:18):
The evidence shows, and really good studies, including like randomized
controlled trials and everything, where they compare people who are
doing intermittent fasting and those doing caloric restriction. There really
isn't any significant difference in weight loss, There's no significant
difference in heart health or other metabolic markers. So really
(14:42):
the difference when it comes down to intermittent fasting is
if your coloric intake remains the same, you aren't going
to see that weight loss. You aren't going to see
the metabolic changes or the other reported benefits.
Speaker 1 (14:56):
Okay, interesting, So if you consume the same number of
calories during your ear window as you would have had
throughout the day, there's no significant difference right right now
in terms of the claims around the benefits of internet
and fasting, what does the current medical evidence say and
where is it still kind of weak?
Speaker 4 (15:14):
So the benefits will show short term studies, and most
of those are up to twelve weeks. There are a
few that last a year, but they will shows a
moderate weight loss, but similar to what we see in
cleric restriction. There is some improvement in insulin sensitivity, and
we have reasonable evidence for that. If we're going to
(15:34):
improve insulin sensitivity, maybe we'll see some improvement in pre
diabetes and metabolic syndrome and type two diabetes management, and
maybe some improvement in LDL or blood pressure, but those
changes aren't necessarily significant. Not very clear evidence for living longer,
healthier lives than humans. That's mainly in animals. Cancer prevention
(15:59):
immortality is something that can be widely advertised, but there's
very limited data, no high quality studies for this, No
high quality studies that shows intermittent fasting can prevent cancer
nor improve your treatment. Are there studies that are ongoing
to look at this, absolutely, but nothing convincing currently.
Speaker 1 (16:20):
Doctor Shreever, I want to play you something from our guest, Alcavadlo.
He talked a bit about intermittent fasting and mental clarity.
Speaker 2 (16:27):
I don't know how much scientific validation there is to
what I'm about to say, but anecdotally speaking, I've certainly
experienced this, and I've talked to other people who've experienced this.
It feels like your senses become a little more acute
when you haven't eaten for a long time. Your mind
just gets a little sharper. Everything seems to get a
little sharper.
Speaker 1 (16:49):
Are there studies around the cognitive benefits to add sharpness
or focus or anything like that.
Speaker 4 (16:55):
Just like most of the studies for intermittent fasting, there
is some possibility of improvement and cognitive benefits, but these
are very short term studies and it isn't consistent across populations.
The high quality meta analysis data doesn't show any benefit
versus a fed state. You know, so fasting is not
(17:15):
any better than a fed state. It's very neutral in
healthy adults in general. As far as studies go, the
best evidence for improving your cognition is still back to
exercise and adequate sleep. The studies on this again, we're
just not finding significantly long enough studies or even significant
data that fasting in whatever form is superior to just
(17:38):
a healthy diet.
Speaker 1 (17:39):
What's your overall take on the internet and fasting trend?
Do you have like a top level Here's how I
feel about it.
Speaker 4 (17:46):
Yeah, I guess in general, I just don't think that
evidence is there. There really is an evidence to show
that it's a better plan than others, or that it's
really even good. For one, if it does meet your
needs to improve your health, I think it's okay, but
you still have to get back to looking at what
is the content of what you're eating. There's risk to
(18:08):
it too, and so you have to think about that.
It can sound great, but it still takes some insight
in knowing what you're eating and what does that do
for your body, and are you including things that are
important to maintain your muscle mass, your bone density, your
basal metabolic rate, and even to live longer healthier. Because
if you're just focusing on that this is a great
(18:29):
plan for weight loss and you're not improving your nutritional choices,
you're not going to see the long term benefits of
what we're looking for as we improve our lifestyle, which
is improved heart health, less disease, less cancer risk, and
living longer and healthier and have more energy. So it's
really not a great plan just isolated by itself.
Speaker 1 (18:54):
I should point out here that both our guests Jin
and Al talk to me about eating clean, and I
have to be honest, I didn't know entirely what that
meant from a scientific perspective, so I went to the dictionary,
and I found that it means consuming food that has
been processed or refined as little as possible, and is
free from additives or other artificial substances. You may have
(19:15):
heard this called whole food, so they eat clean whole
foods during their eating windows. The quality of their diet,
though is important, it's likely also a contributing factor to
their overall results. Okay, doctor Shreever, I want to play
one more clip from Gin because she sounds very clinical
and official while describing her three goals of intermittent fasting.
Speaker 3 (19:39):
So our first fasting goal is we want to keep
insulin low. So of course we don't eat food because
insulin is released in response to eating. That's normal, that's physiology,
and so we keep insulin low. We don't have anything
that tastes sweet or fruity. We're not having you know,
herbal tea that has a sweet flavor profile, black coffee.
Bitter flavors not cause insulin response. So that's why black coffee,
(20:03):
plain tea with the bitter flavor profiles, those are fine.
So we're not chewing gum, We're not having breath mints,
all of that, nothing with any kind of sweetener in it.
Speaker 1 (20:13):
Okay, doctor Shreever, what's your reaction to the first.
Speaker 4 (20:15):
Goal, Well, any intake is going to trigger insulin, So
I think saying that just avoiding sweet or fruity things
is going to help keep your insulin low. I mean
that makes it sound like if we just avoid those things,
we won't have insulin levels spike. I mean, certainly it's
going to be maybe more steady, but I feel like
(20:37):
it's overstated and how low. And she really did say
that bitter flavors don't trigger insulin, and I just I
don't think that's the case. I don't think there's any
evidence to support, because any intake could really trigger insulin.
Speaker 1 (20:54):
Okay, great, let's hear Jin's second goal.
Speaker 3 (20:57):
Our second fasting goal is we want to happen to
stored fat for fuel. And that is why you're not
putting in, you know, butter in your coffee, because if
you're doing that, you're going to be burning the fuel
from your coffee cup instead of fuel from your body.
Speaker 1 (21:13):
And what are your thoughts about that?
Speaker 4 (21:16):
She talked about tapping a distored fat for fuel. That
could take longer in some people than others, depending on
your stored glycogen levels. But I think in the fastest state,
eventually you're going to use more fat for fuel. That's
what some of our weight management medications are good at
helping our metabolic state change too. But I think that's
(21:38):
going to vary among people, and to some extent I
think that is true.
Speaker 1 (21:44):
Great, and now her third fasting goal.
Speaker 3 (21:47):
Our third fasting goal is we want to have increased autopogy,
but it's upregulated when we are fast and clean and
what down regulates autophagy well, eating, but especially like if
we're eating protein, downregulates autophogy. We want our bodies to
be cleaning up all the junkie stuff so we're not
putting new stuff in. So you want to avoid having
(22:08):
pre workouts or bone broth or anything that's going to
be a source of protein during the fast.
Speaker 1 (22:14):
She's using a lot of medical terms or you know,
science y words here, like autophagy. I had to look
that one up. By the way, I understand it to
mean the process where cells break down and recycle damaged
or old parts to keep the body functioning efficiently. Upregulated
is another way to say autopogy is increased, and downregulated
means the process is suppressed. It's also one of those
(22:37):
concepts that social media tends to very much oversimplify. A
lot of influencers make it sound like fasting instantly flips
some kind of magical cell reset switch. So is what
she's saying here accurate, doctor Schreeber.
Speaker 4 (22:52):
There's no good studies that that happens in humans, And
I think the main thing with people really into intimate
fastening is not eating at all in that fasting window,
and eating protein will decrease the supposed autophagy that's occurring
in there, and so fasting stage is really what helps
(23:15):
they claim with autophagy. But we don't have evidence for
in humans.
Speaker 1 (23:19):
So it seems like generally speaking, she's not saying things
that are necessarily incorrect, but maybe brightening them up a bit,
adding some saturation to it a.
Speaker 4 (23:27):
Little bit, right right, being very confident in them and
that these are true and valid versus the evidence that
doesn't support them completely or strongly.
Speaker 1 (23:37):
Intermittent fasting is not for everyone, I asked doctor Shreever,
who specifically should avoid it.
Speaker 4 (23:43):
Anyone with a history of eating disorder really should be
cautious about considering that, you know, eating disorder. Anyone with
diabetes should do it cautiously and not without medical supervision.
Anyone who is older, you know, that would be one
that I'd be worried about because we want to watch
their nutritional intake. Anyone with nutritional deficiencies or otherwise, I'd
(24:08):
be really cautious of anyone with lower muscle mass. And
back to people with diabetes, anyone with any signs of
insulin resistant should really do that in a supervised fashion.
Speaker 1 (24:19):
Yeah, I mean that makes total sense. I'm glad you
brought up people who have struggled with disordered eating, only
because I lived in San Francisco for a while and
intermittent fasting was very popular. But then there was this
kind of underlying discussion of well, are these men who
are very into intermittent fasting kind of falling into disordered
eating by over controlling their intake.
Speaker 4 (24:43):
Definitely a concern because then they might continue to escalate
the time of fasting.
Speaker 1 (24:48):
Yeah. So if a patient asked, you know, they come
into your office and they say, hey, I've been seeing
these trends online intermittent fasting, how would you guide that conversation.
Speaker 4 (24:57):
I would get back to the evidence for it and
talk about studies looking at intermittent fasting and what the
benefit is and why does it work. So intermittent fasting
works when people are reducing their calories and then that
leads to weight loss. It can certainly be a plan
we can talk about if you're interested, but we still
(25:18):
need to look at the big picture for you. So
when we are working with patients on weight management, not
only are we looking at nutrition, we're looking at physical activity,
how much they move throughout the day, what is their
exercise like behavior, how is their mental health, do they
have a history of eating disorder otherwise, how is their sleep?
Are we looking at medications to help you with weight management,
(25:40):
and then how does this fit into that picture? And
if you're doing intermittent fasting, it might be really hard
to manage side effects of some of the medications we
use in weight management. But back to nutrition, we're still
going to talk about what is that content of your
eating window, and if we're going to focus on physical activity,
when your exercise and when is your nutrition and how
(26:03):
do we make you feel like well enough and have
the energy to complete that exercise? And do it well
and make it effective. That's all still part of the picture.
So I think, yeah, it would go back to does
this fit for you? This is why it works, this
is why it doesn't work. If you're looking at living
longer and healthier, it's back to what is the content
(26:24):
of what you're eating, not the timeframe that's going to
change things for you. If you want to improve your diabetes,
maybe we could use it as a tool and do
some monitoring and see if it's helpful for you. But
we got to watch you closely depending on the type
of diabetes you have. There are studies ongoing for those
with type one diabetes, but I definitely would not want
(26:45):
a person like that unless they're very good at managing
their own blood sugar levels and have good control and
without the direction of their doctor to do that on
their own.
Speaker 1 (26:54):
You mentioned other medications. Is this something where say I
come in and I say, you know, oh, I've heard
of these GLP ones that can help me lose weight,
or I could try this intermittent fasting thing. Would you
say that those are options that kind of reflect each other.
Are the two tools in your tool belt? How do
they compare?
Speaker 4 (27:12):
The best evidence that we can find to correlate the
weight loss with the use of weight loss medicines compared
to intermittent fasting is fairly challenging because the duration of
studies is often different. The best data I can find
on intermittent fasting and the various methods within that last
up to twelve months. So to summarize just the twelve
(27:35):
month data, intermittent fasting produces around three percent at it's
honestly six to twelve months. So if you want to
be specific, alternate day fasting and time restricted eating have
about six percent at twelve months, and then Benjamin and
topepuremate has thirteen percent. Now truck Zone and the appropriate
(27:57):
has ten percent at twelve months. Thetide or what goov
at two point four milligrams is eight point three percent
at twelve months, and that's real world data versus studies.
And turns uppatide is fifteen point three percent at twelve months,
and again that's real world data. So the real world
(28:18):
data means we're just studying people out in the general population,
working with their individual physicians and clinicians, and the various
education around that nutrition might or an exercise might be different.
Speaker 1 (28:32):
One big takeaway is that intermittent fasting can be effective
for weight loss. That is what those percentages that doctor
Shreever just mentioned are referring to, but its results are
generally modest compared to newer medical obesity treatments. In other words,
intermittent fasting may help you lose weight, but it's not
a magic bullet, and the online hype around intermittent fasting
(28:54):
can outpace the actual data. Doctor Shreever also warned that
fasting comes with its own own set of complications.
Speaker 4 (29:02):
Well, then you have a shorter timeframe to get your
nutrients in, so you might become vitamin deficient or might
struggle to get enough protein and to keep your muscle
mass up. Those would be some of the main concerns. Also,
depending on how your insulin response is and blood sugar responses,
you might run a lower blood sugar and just really
feel foggy or not well, and also that can disrupt sleep.
Speaker 1 (29:26):
There's also the social media trend it's promoting this intermitten
fasting as a metabolic reset. Another kind of sound science
y is there any medical basis for that idea?
Speaker 4 (29:38):
It's more of a marketing phrase really than a medical one.
Our body is very highly adapted and doesn't reset in
any permanent way, and any benefits will tend to level
off as your body adjusts. So it kind of sounds
like it's a permanent solution, when really it's temporarily. Our
body is going to readjust to the current situation and
(29:59):
we can permanently reset anything. Obesity is a disease, so
it takes a lifetime of treatment or monitoring or watching
for you can improve someone's be ami to normal. That
your body's going to tend to go back if you
don't keep an.
Speaker 2 (30:15):
Eye on it.
Speaker 1 (30:16):
So when would one medically recommend an intermittent fast.
Speaker 4 (30:22):
I think if it makes it easy for one to
work on improving their nutrition and you help them create
a plan about what does that look like for them
and what they typically eat, If that's the best way
to help someone simply get into a process for weight
management that might be acceptable to use, but follow up
(30:43):
with them closely to see how is it going, how
do they feel doing it, how is their hunger responding,
how sustainable is it for them? And when it becomes challenging,
then how do we move on from there?
Speaker 1 (30:57):
So there are times to recommend it. Potentially it is
very personal.
Speaker 4 (31:01):
Yeah, just like anything in weight management, it's very personal
discussion on how to help them improve.
Speaker 1 (31:07):
And that discussion, of course, should be with your doctor.
That seems like a good note to end on. I
think intermittent fasting seems like a very personal decision and lifestyle.
If weight management is your goal, there are better, more
researched methods like quality of diet, physical activity, and medical
options to consider. And there are folks who should definitely
avoid trying intermittent fasting altogether. But if you're curious about
(31:31):
intermittent fasting, check in with your physician first just to
make sure it's the right decision for your health. If
you have tried intermittent fasting, let us know about your
experience down in the comments and what you thought of
this episode. Thanks again to doctor Jen Shreeverer for breaking
down the science behind intermittent fasting, and to Jen Stevens
and Alcavadlo for sharing their stories and experiences with us.
(31:53):
We did it again, y'all. We got to the bottom
of another popular health trend and we still have a
couple episodes to go. In the next episode, we're going
to talk about contrast therapy, you know, going from a
sauna to a cold plunge. We used to do this
in the Midwest all the time. Claims around contrast therapy
are flooding the Internet and popular culture right now, but
(32:13):
don't sweat it. We'll get to the bottom of what's real,
what's not, and what we're still learning. If you have
it already, please hit the subscriber follow button and join
us next time on Health Versus Hype with the American
Medical Association. For more information on all the topics we're covering,
visit Amahealth versus Hype dot org. That's am health vs
Hype dot org. Health Versus Hype is a production of
(32:36):
Ruby Studio from iHeartMedia and the American Medical Association. I'm
traced him Gez. Our producers are Matt Stillow and Pamela Lawrence.
Michael Depoe Wilson is our writer. The show is engineered
and features original music by Matthew Ernest Filler. Health Versus
Hype is intended for educational and informational purposes only and
does not constitute medical advice, diagnosis, or treatment. Always seek
(32:58):
the advice of your physician with any questions you may
have regarding a medical condition.
Ruby.
Speaker 2 (00:07):
It breaks people out. Sometimes what you don't eat breakfast,
what you don't eat launch either. Are you insane? Are
you dye like? People cannot wrap their head around the
way that I eat.
Speaker 3 (00:18):
Diet is what you eat. Intermittent fasting is when you eat.
Speaker 4 (00:23):
I've had a patient claim that fasting was the only
way she could lose weight.
Speaker 1 (00:27):
Intermittent fasting might feel like the latest wellness grace, but
humans have actually been doing versions of it for thousands
of years, sometimes for religion, sometimes for survival, sometimes even
for politics and protests. But over the last couple of decades,
fasting has gone fully mainstream. Now it's all over TikTok,
(00:48):
YouTube and fitness culture, with people claiming it can help
you lose weight, boost your energy, improve your focus, and
optimize your health. The problem is intermittent fasting can mean
almost anything. Aside from your three square meals a day,
There's sixteen eight, where you fast for sixteen hours daily
and restrict your eating to an eight hour window. There's
(01:09):
omad one meal a day, alternate day fasting, five to
two fasting. That's five days of eating a typical diet
and two of eating a calorie restricted diet. There are
juice fasts. Basically everybody has their own version. So when
there are this many options, what actually counts as fasting?
Are we really just restricting calories? Is there something else
(01:30):
going on? And more importantly, is intermittent fasting good for
your health? Or is this another wellness trend getting way
ahead of the science. Clearly we have questions. Like I said,
it might just depend on who you ask. Alcavad Low,
an online fitness influencer and personal trainer, shapes his entire
life around intermittent fasting. He follows a version called OMAD
(01:52):
or one meal a Day.
Speaker 2 (01:54):
So it started by postponing breakfast, and then it became
skipping breakfast, and then it became skipping breakfast and launch
and for the most part, I eat one meal a day.
Speaker 1 (02:05):
And then there's Jen Stevens, a former elementary school teacher
who got so into intermittent fasting that she turned it
into a whole second career. She's written multiple best selling
books on the topic, built a massive online following, and
now hosts a podcast dedicated to the intermittent fasting lifestyle.
Speaker 3 (02:23):
I was on that yo yo. I was either gaining
or losing, and since I lost, the weight with intermittent
fasting over ten years ago. I am steady and it
just feels amazing.
Speaker 1 (02:35):
And of course, doctors know what's science and what's bunk.
People like doctor Jennifer Shreever, a family physician at Sanford
Health who specializes in obesity medicine and long term weight management.
She spends a lot of time separating what intermittent fasting
can do from what social media claims it can do.
Speaker 4 (02:53):
They think that intermittent fasting might optimize our health so
that they can live longer, or they're just looking for
that structured, easy to follow approach and they want to
work on their health and that seems the simplest way
to do it.
Speaker 1 (03:06):
Welcome back to Health Versus Hype with the American Medical Association.
I'm your host Trace Tominguez. Today we're talking about intermittent fasting.
What is it? Can skipping breakfast really improve your health?
What does intermittent fasting do to your body? Join me
as we find out whether intermittent fasting is all health
or just hype. For millions of people, intermittent fasting isn't
(03:44):
just a diet. It's become a lifestyle, and few people
embody that more than Jenn Stevens, who discovered intermittent fasting
while trying to lose weight after years of struggling with
traditional dieting. But while stories like hers have helped fuel
the trends explosive popularity online, doctors and researchers are still
working to understand exactly what fasting does inside the body.
(04:08):
I want to start by understanding why someone would want
to adhere to such a strict way of eating. For that,
let's hear from Jin.
Speaker 3 (04:17):
I have a background, probably like a lot of women
and men, in that I was always chasing the next
best diet plan, right, you know. The first time I
needed to do a diet, turned to calorie counting like
most people. But that didn't work. It wasn't sustainable. I
tried literally everything that came along. I was officially obese,
I weighed two hundred and ten pounds, and I was
(04:40):
sick of it. And so of course I heard about
intermittent fasting. A few people were talking about it, and
I tried it, and I have never stopped since. So
I've been doing intermittent fasting since August of twenty fourteen
without stopping, and for the first time in my entire life.
Speaker 1 (04:56):
I have not yoyod.
Speaker 3 (04:57):
I've been able to maintain after I lost eighty p
I've been able to maintain since I.
Speaker 1 (05:02):
Lost the weight.
Speaker 3 (05:03):
So it is completely different than anything else I ever did.
Speaker 1 (05:07):
So what is intermittent fasting for people who might not know.
Speaker 3 (05:11):
Well, it's basically when we intentionally have periods of time
when we choose to fast, and then we have periods
of time when we choose to eat in an eating window,
so we are either intentionally fasting or our eating window
is open and we are intentionally eating. It's basically a
boundary around the times that you're eating.
Speaker 1 (05:33):
Jin came to intermittent fasting to lose weight, but many
followers of this lifestyle have found their way to intermittent
fasting through wellness and fitness advice. Alcavadlo is an influencer
who focuses on exercise for men in their forties who
are looking for new ways to stay fit and healthy.
Speaker 2 (05:49):
Fitness and exercise was kind of my gateway into being
interested in nutrition. I got more into improving the quality
of the food I was eating and also starting to
pay more attention to the fasting aspect. It all happened
very naturally For me, it never really felt forced. It
never feels like I'm depriving myself. It never feels like
I'm starving myself. To be frank, I'm not super dogmatic
(06:13):
about it. If there's a day where I am absolutely famished,
I'll eat a snack in the middle of the day.
It's fine.
Speaker 1 (06:19):
I want to take a break here and talk about
hunger for a minute. It's more complicated than simply having
an empty stomach. People feel hunger because the body and
the brain are constantly working together to monitor our energy needs.
One of the biggest players is a hormone called grellin.
It's often nicknamed the hunger hormone. When your stomach has
(06:40):
been empty for a while, grellin levels rise and send
signals to the brain telling you it's time to eat.
But blood sugar levels, hormones, sleep, stress, emotions, habits, and
even smell can all influence hunger too. For example, if
you have a habit of always eating lunch at noon,
your body may start triggering hunger signals around that time,
(07:01):
whether you actually need calories or not. During fasting, people
often notice hunger comes in waves rather than increasing endlessly.
That's because hormones like Grellin rise and fall throughout the day,
and the body can gradually adapt to new eating patterns
over time. Al alluded to this a.
Speaker 2 (07:18):
Little Just try to wait a little longer to eat breakfast,
because most people wake up and immediately start eating. They're
not hungry. They do it because it's part of their routine.
And if you actually are hungry fifteen minutes after you
wake up, god bless eat. But sometimes people find out, Oh,
you know what, I drank a glass of water and
I didn't get hungry for a couple hours. And that's
(07:41):
sort of how it happened. Familiar, and I've been doing
that for a long time now.
Speaker 1 (07:45):
Jin shared something similar.
Speaker 3 (07:47):
The thing about hunger is, let's imagine you're not an
intermittent faster, You're just someone who eats typically.
Speaker 1 (07:53):
Yeah, do you have hunger in your day? Sometimes yes,
yeah you do. You have hunger.
Speaker 3 (08:00):
And then you eat and then it goes away, and
then later you're hungry, good, and then you eat and
then it goes away. For intermittent fasters, we have hunger too,
and then it goes away, It fades without eating, and
your body is like, all right, I guess I'll munch
on some stored fat for a while. So the thing
about hunger is once you understand it doesn't build and
(08:23):
build and build and build. When you're fast and clean,
it's not an emergency. You have a little wave of hunger,
you acknowledge it, you do something else, and then you're
not hungry anymore.
Speaker 1 (08:34):
And let's face it, for all of us, but especially
for people trying to lose weight, specifically, evolving diet information
and guidelines can feel confusing.
Speaker 3 (08:44):
You know, should you be vegan, should you be carnivore?
Speaker 4 (08:46):
You know?
Speaker 3 (08:47):
Or plants trying to kill you? I mean, you know,
I can talk about every single diet out there and
what they want you to avoid or what you're allowed
to have or not allowed to have, but we get
so confused. We don't even know what we're supposed to
be eating anymore. But the best part about intermittent fasting
is that it isn't a diet at all. Because diet
is what you eat. Intermittent fasting is when you eat.
(09:11):
So we're all eating a diet, whether it's the standard
American diet or your vegan or your carnivore, or you're
following the Mediterranean diet. You're eating some sort of diet,
but intermittent fasting is when, so it's definitely not a diet.
Like I never say I'm doing the intermittent fasting diet.
Speaker 1 (09:28):
I want to introduce our medical expert now, doctor Jennifer Shreever.
She's been a family physician and obesity medicine specialist for
more than twenty years. I played that clip from Jen
for her, and here's doctor Shreever's reaction to it.
Speaker 4 (09:42):
You know, nutrition is complex, and it kind of seems like,
I'm sure to the normal population that our nutrition advice
has changed a lot across the years. I mean low
carved and low fat. So that's very confusing.
Speaker 1 (09:56):
And she's saying that because it's when you eat, it's
not a diet.
Speaker 4 (10:00):
That seems like a strange way to represent that. I
guess it depends on how you think of the word diet.
I mean, historically, diet is something that helps you lose weight,
and if that's a claim for internet and fasting, I
guess I would classify it as a diet. We try
not to use the word diet because it just has
kind of a negative connotation and it's something that you
(10:21):
do temporarily, right, and maybe that's what she's trying to
say too.
Speaker 1 (10:27):
She definitely talks a lot more about how this is
a lifestyle change and diets are temporary and lifestyle is permanent.
Speaker 4 (10:36):
Yeah, And my practice treating patients for weight management, I'm
trying to create and help you improve your lifestyle in
a way that you feel good in the process, lose weight,
have more energy. I don't want to have a plan
that you graduate from or finish. This is something that
we might continually have to adjust and manage over time.
(10:59):
So I think even people on intermittent fasting are going
to find that they're going to have to adjust and
adapt something over time. So that's giving the sense that
this is a long term solution. Life happens, life changes.
Some of that's under control, a lot of it's not.
There's nothing that is the final answer.
Speaker 1 (11:19):
Yeah, So when someone starts doing intermittent fasting, what happens
to our bodies.
Speaker 4 (11:25):
So what happens is your body will start to shift
from burning blood sugar or glucose to using your stored energy,
so you're fatty tissue during those fasting periods. During your
fed state, you'll probably return to using more sugar. Often also,
as one starts intermittent fasting depending on how they approach it,
(11:47):
but many will have less calorie intake. A person might
cut out that meal and not replace that nutrition later
in the day, so then you're just reducing your caloric
intake and that can contribute to some earth onset of
some initial weight loss, so then that makes you feel successful.
So by fasting, you know, one might have insulin resistance,
(12:08):
So that means that typically with having extra fatty tissue
around that doesn't recognize the insulin you're making, and so
if your blood sugar is not well managed and creeping up,
your body is going to make more insulin because it's
not recognizing that signal that that insulin is there. The
disadvantage to that is insulin wants to store calories, so
it's not managing your blood sugar as well because your
(12:29):
body isn't recognizing but it's still doing its job of
storing calories.
Speaker 1 (12:33):
Let me see if I can explain this a little more. Normally,
after you eat, your body releases insulin to help move
sugar from the blood into your cells so it can
be used for energy. But with insulin resistance, the cells
stop responding to the insulin efficiently, so the sugar stays
in the bloodstream longer to compensate, the pancreas pumps out
(12:56):
more insulin, and then over time, consistently elevated blood sugar
can lead to pre diabetes or type two diabetes and
increase the risk of things like heart disease, nerve damage,
and kidney problems. So creeping up basically means blood sugar
levels are gradually rising beyond what the body can comfortably regulate.
Speaker 4 (13:16):
So if internet and fasting has been shown to reduce
insulin levels and that's their intention, then you might be
storing less of your calories in fat. So that happens
pretty quickly as far as early in the fasting states,
at least as far as what evidence is currently leaning towards.
(13:36):
But does that lead to actual blood sugar control and
improved A one CS is yet to be seen.
Speaker 1 (13:42):
More research is needed. As I like to say, yeah,
and just so we all understand, A one C is
a blood test that measures your average blood sugar levels
looking back over the past two to three months. When
researchers talk about whether intermittent fasting improves A one C,
they're asking whether it meaningfully improves long term blood sugar control,
(14:02):
not just short term changes during the fast But I'm
really curious if intermittent fasting is just a different way
to restrict calories than your average diet, or if something
special is taking place in the body during intermittent fasting.
Speaker 4 (14:18):
The evidence shows, and really good studies, including like randomized
controlled trials and everything, where they compare people who are
doing intermittent fasting and those doing caloric restriction. There really
isn't any significant difference in weight loss, There's no significant
difference in heart health or other metabolic markers. So really
(14:42):
the difference when it comes down to intermittent fasting is
if your coloric intake remains the same, you aren't going
to see that weight loss. You aren't going to see
the metabolic changes or the other reported benefits.
Speaker 1 (14:56):
Okay, interesting, So if you consume the same number of
calories during your ear window as you would have had
throughout the day, there's no significant difference right right now
in terms of the claims around the benefits of internet
and fasting, what does the current medical evidence say and
where is it still kind of weak?
Speaker 4 (15:14):
So the benefits will show short term studies, and most
of those are up to twelve weeks. There are a
few that last a year, but they will shows a
moderate weight loss, but similar to what we see in
cleric restriction. There is some improvement in insulin sensitivity, and
we have reasonable evidence for that. If we're going to
(15:34):
improve insulin sensitivity, maybe we'll see some improvement in pre
diabetes and metabolic syndrome and type two diabetes management, and
maybe some improvement in LDL or blood pressure, but those
changes aren't necessarily significant. Not very clear evidence for living longer,
healthier lives than humans. That's mainly in animals. Cancer prevention
(15:59):
immortality is something that can be widely advertised, but there's
very limited data, no high quality studies for this, No
high quality studies that shows intermittent fasting can prevent cancer
nor improve your treatment. Are there studies that are ongoing
to look at this, absolutely, but nothing convincing currently.
Speaker 1 (16:20):
Doctor Shreever, I want to play you something from our guest, Alcavadlo.
He talked a bit about intermittent fasting and mental clarity.
Speaker 2 (16:27):
I don't know how much scientific validation there is to
what I'm about to say, but anecdotally speaking, I've certainly
experienced this, and I've talked to other people who've experienced this.
It feels like your senses become a little more acute
when you haven't eaten for a long time. Your mind
just gets a little sharper. Everything seems to get a
little sharper.
Speaker 1 (16:49):
Are there studies around the cognitive benefits to add sharpness
or focus or anything like that.
Speaker 4 (16:55):
Just like most of the studies for intermittent fasting, there
is some possibility of improvement and cognitive benefits, but these
are very short term studies and it isn't consistent across populations.
The high quality meta analysis data doesn't show any benefit
versus a fed state. You know, so fasting is not
(17:15):
any better than a fed state. It's very neutral in
healthy adults in general. As far as studies go, the
best evidence for improving your cognition is still back to
exercise and adequate sleep. The studies on this again, we're
just not finding significantly long enough studies or even significant
data that fasting in whatever form is superior to just
(17:38):
a healthy diet.
Speaker 1 (17:39):
What's your overall take on the internet and fasting trend?
Do you have like a top level Here's how I
feel about it.
Speaker 4 (17:46):
Yeah, I guess in general, I just don't think that
evidence is there. There really is an evidence to show
that it's a better plan than others, or that it's
really even good. For one, if it does meet your
needs to improve your health, I think it's okay, but
you still have to get back to looking at what
is the content of what you're eating. There's risk to
(18:08):
it too, and so you have to think about that.
It can sound great, but it still takes some insight
in knowing what you're eating and what does that do
for your body, and are you including things that are
important to maintain your muscle mass, your bone density, your
basal metabolic rate, and even to live longer healthier. Because
if you're just focusing on that this is a great
(18:29):
plan for weight loss and you're not improving your nutritional choices,
you're not going to see the long term benefits of
what we're looking for as we improve our lifestyle, which
is improved heart health, less disease, less cancer risk, and
living longer and healthier and have more energy. So it's
really not a great plan just isolated by itself.
Speaker 1 (18:54):
I should point out here that both our guests Jin
and Al talk to me about eating clean, and I
have to be honest, I didn't know entirely what that
meant from a scientific perspective, so I went to the dictionary,
and I found that it means consuming food that has
been processed or refined as little as possible, and is
free from additives or other artificial substances. You may have
(19:15):
heard this called whole food, so they eat clean whole
foods during their eating windows. The quality of their diet,
though is important, it's likely also a contributing factor to
their overall results. Okay, doctor Shreever, I want to play
one more clip from Gin because she sounds very clinical
and official while describing her three goals of intermittent fasting.
Speaker 3 (19:39):
So our first fasting goal is we want to keep
insulin low. So of course we don't eat food because
insulin is released in response to eating. That's normal, that's physiology,
and so we keep insulin low. We don't have anything
that tastes sweet or fruity. We're not having you know,
herbal tea that has a sweet flavor profile, black coffee.
Bitter flavors not cause insulin response. So that's why black coffee,
(20:03):
plain tea with the bitter flavor profiles, those are fine.
So we're not chewing gum, We're not having breath mints,
all of that, nothing with any kind of sweetener in it.
Speaker 1 (20:13):
Okay, doctor Shreever, what's your reaction to the first.
Speaker 4 (20:15):
Goal, Well, any intake is going to trigger insulin, So
I think saying that just avoiding sweet or fruity things
is going to help keep your insulin low. I mean
that makes it sound like if we just avoid those things,
we won't have insulin levels spike. I mean, certainly it's
going to be maybe more steady, but I feel like
(20:37):
it's overstated and how low. And she really did say
that bitter flavors don't trigger insulin, and I just I
don't think that's the case. I don't think there's any
evidence to support, because any intake could really trigger insulin.
Speaker 1 (20:54):
Okay, great, let's hear Jin's second goal.
Speaker 3 (20:57):
Our second fasting goal is we want to happen to
stored fat for fuel. And that is why you're not
putting in, you know, butter in your coffee, because if
you're doing that, you're going to be burning the fuel
from your coffee cup instead of fuel from your body.
Speaker 1 (21:13):
And what are your thoughts about that?
Speaker 4 (21:16):
She talked about tapping a distored fat for fuel. That
could take longer in some people than others, depending on
your stored glycogen levels. But I think in the fastest state,
eventually you're going to use more fat for fuel. That's
what some of our weight management medications are good at
helping our metabolic state change too. But I think that's
(21:38):
going to vary among people, and to some extent I
think that is true.
Speaker 1 (21:44):
Great, and now her third fasting goal.
Speaker 3 (21:47):
Our third fasting goal is we want to have increased autopogy,
but it's upregulated when we are fast and clean and
what down regulates autophagy well, eating, but especially like if
we're eating protein, downregulates autophogy. We want our bodies to
be cleaning up all the junkie stuff so we're not
putting new stuff in. So you want to avoid having
(22:08):
pre workouts or bone broth or anything that's going to
be a source of protein during the fast.
Speaker 1 (22:14):
She's using a lot of medical terms or you know,
science y words here, like autophagy. I had to look
that one up. By the way, I understand it to
mean the process where cells break down and recycle damaged
or old parts to keep the body functioning efficiently. Upregulated
is another way to say autopogy is increased, and downregulated
means the process is suppressed. It's also one of those
(22:37):
concepts that social media tends to very much oversimplify. A
lot of influencers make it sound like fasting instantly flips
some kind of magical cell reset switch. So is what
she's saying here accurate, doctor Schreeber.
Speaker 4 (22:52):
There's no good studies that that happens in humans, And
I think the main thing with people really into intimate
fastening is not eating at all in that fasting window,
and eating protein will decrease the supposed autophagy that's occurring
in there, and so fasting stage is really what helps
(23:15):
they claim with autophagy. But we don't have evidence for
in humans.
Speaker 1 (23:19):
So it seems like generally speaking, she's not saying things
that are necessarily incorrect, but maybe brightening them up a bit,
adding some saturation to it a.
Speaker 4 (23:27):
Little bit, right right, being very confident in them and
that these are true and valid versus the evidence that
doesn't support them completely or strongly.
Speaker 1 (23:37):
Intermittent fasting is not for everyone, I asked doctor Shreever,
who specifically should avoid it.
Speaker 4 (23:43):
Anyone with a history of eating disorder really should be
cautious about considering that, you know, eating disorder. Anyone with
diabetes should do it cautiously and not without medical supervision.
Anyone who is older, you know, that would be one
that I'd be worried about because we want to watch
their nutritional intake. Anyone with nutritional deficiencies or otherwise, I'd
(24:08):
be really cautious of anyone with lower muscle mass. And
back to people with diabetes, anyone with any signs of
insulin resistant should really do that in a supervised fashion.
Speaker 1 (24:19):
Yeah, I mean that makes total sense. I'm glad you
brought up people who have struggled with disordered eating, only
because I lived in San Francisco for a while and
intermittent fasting was very popular. But then there was this
kind of underlying discussion of well, are these men who
are very into intermittent fasting kind of falling into disordered
eating by over controlling their intake.
Speaker 4 (24:43):
Definitely a concern because then they might continue to escalate
the time of fasting.
Speaker 1 (24:48):
Yeah. So if a patient asked, you know, they come
into your office and they say, hey, I've been seeing
these trends online intermittent fasting, how would you guide that conversation.
Speaker 4 (24:57):
I would get back to the evidence for it and
talk about studies looking at intermittent fasting and what the
benefit is and why does it work. So intermittent fasting
works when people are reducing their calories and then that
leads to weight loss. It can certainly be a plan
we can talk about if you're interested, but we still
(25:18):
need to look at the big picture for you. So
when we are working with patients on weight management, not
only are we looking at nutrition, we're looking at physical activity,
how much they move throughout the day, what is their
exercise like behavior, how is their mental health, do they
have a history of eating disorder otherwise, how is their sleep?
Are we looking at medications to help you with weight management,
(25:40):
and then how does this fit into that picture? And
if you're doing intermittent fasting, it might be really hard
to manage side effects of some of the medications we
use in weight management. But back to nutrition, we're still
going to talk about what is that content of your
eating window, and if we're going to focus on physical activity,
when your exercise and when is your nutrition and how
(26:03):
do we make you feel like well enough and have
the energy to complete that exercise? And do it well
and make it effective. That's all still part of the picture.
So I think, yeah, it would go back to does
this fit for you? This is why it works, this
is why it doesn't work. If you're looking at living
longer and healthier, it's back to what is the content
(26:24):
of what you're eating, not the timeframe that's going to
change things for you. If you want to improve your diabetes,
maybe we could use it as a tool and do
some monitoring and see if it's helpful for you. But
we got to watch you closely depending on the type
of diabetes you have. There are studies ongoing for those
with type one diabetes, but I definitely would not want
(26:45):
a person like that unless they're very good at managing
their own blood sugar levels and have good control and
without the direction of their doctor to do that on
their own.
Speaker 1 (26:54):
You mentioned other medications. Is this something where say I
come in and I say, you know, oh, I've heard
of these GLP ones that can help me lose weight,
or I could try this intermittent fasting thing. Would you
say that those are options that kind of reflect each other.
Are the two tools in your tool belt? How do
they compare?
Speaker 4 (27:12):
The best evidence that we can find to correlate the
weight loss with the use of weight loss medicines compared
to intermittent fasting is fairly challenging because the duration of
studies is often different. The best data I can find
on intermittent fasting and the various methods within that last
up to twelve months. So to summarize just the twelve
(27:35):
month data, intermittent fasting produces around three percent at it's
honestly six to twelve months. So if you want to
be specific, alternate day fasting and time restricted eating have
about six percent at twelve months, and then Benjamin and
topepuremate has thirteen percent. Now truck Zone and the appropriate
(27:57):
has ten percent at twelve months. Thetide or what goov
at two point four milligrams is eight point three percent
at twelve months, and that's real world data versus studies.
And turns uppatide is fifteen point three percent at twelve months,
and again that's real world data. So the real world
(28:18):
data means we're just studying people out in the general population,
working with their individual physicians and clinicians, and the various
education around that nutrition might or an exercise might be different.
Speaker 1 (28:32):
One big takeaway is that intermittent fasting can be effective
for weight loss. That is what those percentages that doctor
Shreever just mentioned are referring to, but its results are
generally modest compared to newer medical obesity treatments. In other words,
intermittent fasting may help you lose weight, but it's not
a magic bullet, and the online hype around intermittent fasting
(28:54):
can outpace the actual data. Doctor Shreever also warned that
fasting comes with its own own set of complications.
Speaker 4 (29:02):
Well, then you have a shorter timeframe to get your
nutrients in, so you might become vitamin deficient or might
struggle to get enough protein and to keep your muscle
mass up. Those would be some of the main concerns. Also,
depending on how your insulin response is and blood sugar responses,
you might run a lower blood sugar and just really
feel foggy or not well, and also that can disrupt sleep.
Speaker 1 (29:26):
There's also the social media trend it's promoting this intermitten
fasting as a metabolic reset. Another kind of sound science
y is there any medical basis for that idea?
Speaker 4 (29:38):
It's more of a marketing phrase really than a medical one.
Our body is very highly adapted and doesn't reset in
any permanent way, and any benefits will tend to level
off as your body adjusts. So it kind of sounds
like it's a permanent solution, when really it's temporarily. Our
body is going to readjust to the current situation and
(29:59):
we can permanently reset anything. Obesity is a disease, so
it takes a lifetime of treatment or monitoring or watching
for you can improve someone's be ami to normal. That
your body's going to tend to go back if you
don't keep an.
Speaker 2 (30:15):
Eye on it.
Speaker 1 (30:16):
So when would one medically recommend an intermittent fast.
Speaker 4 (30:22):
I think if it makes it easy for one to
work on improving their nutrition and you help them create
a plan about what does that look like for them
and what they typically eat, If that's the best way
to help someone simply get into a process for weight
management that might be acceptable to use, but follow up
(30:43):
with them closely to see how is it going, how
do they feel doing it, how is their hunger responding,
how sustainable is it for them? And when it becomes challenging,
then how do we move on from there?
Speaker 1 (30:57):
So there are times to recommend it. Potentially it is
very personal.
Speaker 4 (31:01):
Yeah, just like anything in weight management, it's very personal
discussion on how to help them improve.
Speaker 1 (31:07):
And that discussion, of course, should be with your doctor.
That seems like a good note to end on. I
think intermittent fasting seems like a very personal decision and lifestyle.
If weight management is your goal, there are better, more
researched methods like quality of diet, physical activity, and medical
options to consider. And there are folks who should definitely
avoid trying intermittent fasting altogether. But if you're curious about
(31:31):
intermittent fasting, check in with your physician first just to
make sure it's the right decision for your health. If
you have tried intermittent fasting, let us know about your
experience down in the comments and what you thought of
this episode. Thanks again to doctor Jen Shreeverer for breaking
down the science behind intermittent fasting, and to Jen Stevens
and Alcavadlo for sharing their stories and experiences with us.
(31:53):
We did it again, y'all. We got to the bottom
of another popular health trend and we still have a
couple episodes to go. In the next episode, we're going
to talk about contrast therapy, you know, going from a
sauna to a cold plunge. We used to do this
in the Midwest all the time. Claims around contrast therapy
are flooding the Internet and popular culture right now, but
(32:13):
don't sweat it. We'll get to the bottom of what's real,
what's not, and what we're still learning. If you have
it already, please hit the subscriber follow button and join
us next time on Health Versus Hype with the American
Medical Association. For more information on all the topics we're covering,
visit Amahealth versus Hype dot org. That's am health vs
Hype dot org. Health Versus Hype is a production of
(32:36):
Ruby Studio from iHeartMedia and the American Medical Association. I'm
traced him Gez. Our producers are Matt Stillow and Pamela Lawrence.
Michael Depoe Wilson is our writer. The show is engineered
and features original music by Matthew Ernest Filler. Health Versus
Hype is intended for educational and informational purposes only and
does not constitute medical advice, diagnosis, or treatment. Always seek
(32:58):
the advice of your physician with any questions you may
have regarding a medical condition.
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