It’s going to upset people on the low-carb bandwagon but recent evidence shows that high carb diets can make you live longer, maybe even longer than calorie restriction.
Calorie restriction (CR), eating less of every kind of calorie, improves cardiometabolic risk factors, generic hallmarks of aging, brain function and makes all kinds of animals live longer. But being hungry all the time is one of the few things that are worse than death. We need to find a better way to get those benefits.
Mice consuming a low-protein, high-carbohydrate, low-fat diet (LPHC, protein/carbohydrate ratio ~1/10) lived longest and were healthier in old age, even when compared to calorie restriction achieved by dilution of chow with non-digestible no calorie fiber. The beneficial effects of LPHC diets on lifespan are conserved across a range of organisms from invertebrates to mice. The observation that eating as much as you want of this diet is beneficial for lifespan and late-in-life cardiometabolic health suggest that it may also delay brain aging. (1)
Lean body mass and overall body mass was the same in both diets but body fat was lower in the CR diet. Insulin metabolism and cholesterol was the same. Fibroblast Growth Factor 21 is a regulator of energy metabolism in the liver and fat tissue. It was much higher in the most protein restricted diet.
It seems like protein is the poison. The lowest percentage of protein, along with plenty of carbs works the best. I think there is a high protein bandwagon too that’s going to be upset with this information.
Looking at what genes are regulated up or down by these diet manipulations will help us zero in on the mechanisms of these observations. A very low-protein, high-carbohydrate diet may be a more feasible nutritional intervention to delay brain aging than hunger. Maybe it’s not how much you eat but what you eat after all. But it won’t fix your body shape.
You have to eat some protein because your body, besides water, is mostly made of protein. But not very much.
1. Wahl D. et al. Comparing the Effects of Low-Protein and High-Carbohydrate Diets and Caloric Restriction on Brain Aging in Mice. Cell Reports 2018;25(8):2234-43. https://doi.org/10.1016/j.celrep.2018.10.070