Research with animals shows that calorie restriction can extend lifespan. In numerous animal species, from yeasts to rodents and primates, a diet with 20-40% fewer calories leads to a significantly longer lifespan, sometimes as much as 30-50% longer134.
Scientists first discovered this phenomenon in the 1930s, and over the past 90 years it has been replicated in species ranging from worms to monkeys. Subsequent studies also showed that many of the animals put on rations were less likely to develop cancer and other chronic diseases associated with aging.
Calorie restriction appears to slow the aging process and reduce the risk of age-related diseases such as cancer, diabetes and neurodegenerative disorders.
The precise mechanisms have not yet been fully elucidated, but factors such as reduced oxidative stress, better insulin sensitivity and activated autophagy (cell remediation) may play a role.
Experts also debate
still talking about how it works, and whether the number of calories consumed or the time window in which they are eaten (also known as intermittent fasting) is that more important.
Human studies
- Long-term studies of strict calorie restriction in humans are scarce due to the practical and ethical challenges. You can hardly let thousands of people starve for thousands of years without knowing whether it will lead to anything.
- Some short-term studies show beneficial effects on biomarkers of aging, but the impact on actual lifespan extension is unknown.
- Intermittent fasting, a form of periodic calorie restriction, appears to offer some health benefits, but the long-term effects are still unclear.
- In general, experts suggest that calorie restriction may extend lifespan, but a balanced diet and healthy lifestyle are just as important.
Although calorie restriction appears promising based on animal studies, more long-term research in humans is needed to determine its effects on lifespan extension. A healthy, varied diet in combination with other lifestyle factors such as exercise seems to be the best approach for a long and healthy life.
