Can eating less really help you live longer? A new study says yes, but with a crucial twist. Scientists have found that it’s not just about cutting calories but how well your body adapts to dietary changes that truly matters for longevity.
The study, published in Nature, showed how different forms of dietary restriction can significantly extend the lifespan of mice. Researchers say their findings not only confirm the life-extending benefits of calorie restriction but also reveal that intermittent fasting can have similar effects, even without reducing overall calorie intake.
Led by scientists from Calico Life Sciences and The Jackson Laboratory, the research involved an extensive examination of 937 genetically diverse female mice. The rodents were split into five dietary groups: one with unrestricted access to food, two with calorie restrictions (60% and 80% of baseline calories), and two with intermittent fasting (one or two consecutive days per week without food). The mice were then monitored throughout their lives, with regular health assessments and blood tests.
The study found that both calorie restriction and intermittent fasting extended the lifespan of mice, with effects proportional to the degree of restriction. Mice on 40% calorie restriction lived about nine months longer than those allowed to eat as much as they wanted. That’s equivalent to extending a human lifespan by over a decade!
Even more intriguing, mice that fasted for one or two days per week also experienced significant lifespan extensions, with those fasting for two days living longer than those fasting for one. That’s despite consuming nearly the same amount of food overall as their unrestricted counterparts.
The researchers didn’t just measure how long the mice lived; they also conducted an exhaustive analysis of their health throughout their lives. They examined everything from body composition and metabolic rates to immune system function and cognitive abilities. This comprehensive approach allowed them to paint a detailed picture of how dietary restriction affects not just lifespan, but overall health and aging.
One of the most surprising findings was that many of the health benefits typically associated with dietary restriction, such as improved glucose metabolism and reduced body fat, didn’t necessarily translate into a longer life. In fact, some mice on restricted diets lived longer despite showing less improvement in these typical health markers.
“Our study really points to the importance of resilience,” says Gary Churchill, Karl Gunnar Johansson Chair and professor at JAX who led the study, in a statement. “The most robust animals keep their weight on even in the face of stress and caloric restriction, and they are the ones that live the longest. It also suggests that a more moderate level of calorie restriction might be the way to balance long-term health and lifespan.”
This discovery challenges the long-held belief that calorie restriction extends life primarily by counteracting the negative effects of obesity. Instead, it suggests that dietary restriction might work through more complex mechanisms that we don’t yet fully understand.
Source: https://studyfinds.org/7-day-cycle-fasting-boost-lifespan/?nab=0