On October 12, China News reported on a groundbreaking study published in the prestigious scientific journal Nature, revealing new insights into aging research. The study indicates that while dietary restriction—essentially controlling food intake—can extend the lifespan of mice, its various impacts on health may not align directly with longevity.
The findings stem from research conducted on nearly 1,000 genetically diverse mice, shedding light on the intricate relationship between dietary restriction and lifespan. This study suggests that genetic factors may play a more significant role in determining lifespan than dietary interventions alone.
According to the paper, dietary restriction includes methods such as caloric restriction and intermittent fasting, both of which show tremendous potential in enhancing human health and longevity. However, there is still limited understanding regarding the effectiveness and safety of different dietary restriction approaches.
To address this, Gary A. Churchill, a co-author of the study from the Jackson Laboratory, along with his colleagues, utilized 960 genetically diverse female mice to explore how caloric restriction and intermittent fasting impact health and lifespan. These mice represent a range of physiological traits that may be applicable across different species. They were randomly assigned one of five diets: ad libitum feeding (unrestricted access to food), one day of fasting per week, two consecutive fasting days per week, and caloric restrictions of either 20% or 40% of their baseline food intake.
The study found that all forms of dietary restriction extended the mice’s lifespan, with a proportional effect based on the level of restriction. Notably, only caloric restriction significantly slowed the aging process; the degree of lifespan extension remained consistent regardless of the mice’s body weight. Interestingly, the lifespan extension effects of intermittent fasting did not apply to mice that were heavier prior to intervention.
Among the dietary groups, one of the strongest predictors of lifespan was the ability to maintain body weight under experimental stress. While dietary restriction was found to improve metabolic traits—such as fasting blood glucose—this improvement did not directly correlate with longevity. Ultimately, though dietary restrictions produced multiple effects, the study concluded that genetic background has a more substantial impact on lifespan than dietary interventions.
Accompanying the study, a commentary from peer experts published in Nature emphasizes that, for mice, the metabolic benefits of dietary restriction do not necessarily translate into increased lifespan. Further research is essential to determine whether intermittent fasting and caloric restriction can similarly extend human lifespan.
About the author