A University of Sydney study has found that a low-protein, high-carbohydrate diet appears to be the most effective for stimulating a hormone with life-extending and obesity-fighting benefits.
The results, published in the medical journal Cell Metabolism, point to the value of the little-known fibroblast growth factor 21, the so-called “fountain of youth” hormone produced primarily in the liver.
Researchers from the university’s Charles Perkins Centre monitored FGF21 in mice, tracking for the first time how macronutrients interacted to affect levels of the hormone.
More than 800 mice were fed one of 25 diets with varying amounts of protein, carbohydrate and fat.
Lead researcher Samantha Solon-Biet said previous studies had shown that FGF21 played a role in curbing appetite, moderating metabolism and extending lifespan. But little had been known before now about how the hormone was triggered and released in the body. The study found FGF21 levels were highly dependent on the balance of protein to carbohydrate.
“Despite the popularity of high protein paleo diets, our research suggests the exact opposite may be best for us as we age, that a low-protein, high-carbohydrate diet is the most beneficial for late-life health and longevity,” Dr Solon-Biet said.
“These findings take us one step closer to understanding how FGF21 works and being able to use it to help people live longer and healthier lives.”
The study also found that when high-carbohydrate diets increased levels of the hormone, mice compensated for the excess by burning more energy.
This year a University of Sydney study of mice found that a low-protein, high-carbohydrate diet provided similar benefits to a calorie-restricting diet, including lowering cholesterol and improving insulin sensitivity.