Although the specific reason why eating less would make an animal or human live longer is unknown, many theories point toward evolution. One notion is that calorie restriction increases an animal’s biological resistance to physical shocks. For instance, mice on a calorie-restricted diet show increased resilience to toxins and quicker recovery from damage.
In addition, calorie restriction makes the body use fuel sources other than glucose, which is advantageous for metabolic health and, eventually, longer life, according to aging specialists. Numerous scientists cited the process of autophagy, in which damaged cell components are consumed by the body and converted to energy. This reduces the incidence of various age-related illnesses and improves cell function.
The results regarding calorie restriction and longevity show several major exceptions. He discovered that while a greater proportion of the mice truly had reduced lifespans, some of them did live longer when they consumed less food.
What role does intermittent fasting play in this matter?
Amidst these contradictory findings, several researchers question whether an additional factor—the window of time during which an animal consumes calories—might be equally, if not more, significant than the caloric intake of the animal.
Another study featured a significant distinction between the two monkey trials: the calorie-restricted animals were only fed once a day, and any food that remained was taken away by the researchers in the late afternoon, forcing the animals to fast for roughly sixteen hours. The animals in National Institute on aging study were fed twice a day and had their food left out overnight. The longest-living monkeys were those from Wisconsin.
The animals were fed the same low-calorie meal by the scientists, but some were only fed it for two hours, others for twelve, and still another group for twenty-four. The low-calorie mice with 24-hour access to food had a 10% higher life duration than the control group of mice, but the low-calorie mice that were fed during certain time frames had a 35% longer life span.
Rafael de Cabo, a senior investigator at the NIA who assisted in leading the monkey study there, now believes that while calorie restriction is vital for life, the quantity of time spent eating — and not eating — every day is just as significant. This is based on a collection of studies. And that could be the case!
(The author, Dana G. Smith, is a writer.)
