Fasting: The Quick Way to Better Health?

Studies show fasting could improve outcomes for a huge range of medical conditions... in mice. Do those benefits cross over to humans too?

By Liz Garton

Associate Professor Alexander Tups from the Neuroendocrinology and Brain Health Centre at Otago University said fasting looks promising for treating certain autoimmune conditions, reducing rates of cancer, improving general gut health and brain function and mental health too.

"The most recent research suggests the body rejuvenates during fasting and that it increases lifespan," said Dr Tups.

"Another thing that has been show, is that these intermittent fasting periods can directly affect our brain. So, it can increase neurogenesis," he said, "We need to do more research to confirm this. But that would be really interesting because then it would also improve cognition and it could be beneficial to treat dementia, for example."

And Dr Tups' own research suggests timing could be a factor.

"So we found that if we give food to certain times of the day, we actually have an effect on the hormone that regulates our body weight," he said.

The hormone is leptin and it makes us eat less and burn our energy. Tups' research found that in the morning the hormone works really well.

"So it was around breakfast time to lunchtime," said Tups.

Which would suggest eating over this time and then skipping dinner might be most effective.

But again, this is research done in mice - so Dr Tups is unsure if it can be translated to humans.

Professor Rachael Taylor, director of the Edgar Diabetes and Obesity Research Centre at Otago University was involved in the SWIFT study, which looked at different ways of sort of assisting people to lose weight.

The subjects were able to choose which diet would suit them and many chose fasting.

"A lot of the people liked the idea of fasting," said Taylor, "They felt that it was going to be much simpler, but in reality, they found that fasting or the fasting days, not surprisingly, really quite difficult because they could only eat less than a quarter of their normal dietary intake."

Taylor said generally speaking, a lot of women found fasting difficult to incorporate into their lives.

"Particularly if they were the main food provider in their households, they found it quite difficult to fast and actually cook for everyone else."

Interestingly, the study did not find a lot of difference in the outcomes for the different monitoring systems nor the different diets…

Go to this episode on rnz.co.nz for more details