Fasting , especially intermittent fasting , has become a topic of great interest in recent years, not only for its effects on weight loss , but also for its potential impact on longevity . A new study published in the journal Nature has shed light on how calorie restriction and intermittent fasting may affect health and lifespan, at least in animal models.
Can fasting prolong your life?
The study found that all forms of food restriction tested in mice led to an increase in life expectancy . Specifically, mice given either a 20% or 40% calorie restriction lived longer than those given unlimited access to food. However, the scientists also found that these effects were not uniform across all mice. The animals’ response to calorie restriction varied greatly, highlighting how genetics influence their ability to benefit from such dietary interventions. While calorie restriction improved things like blood glucose levels and body fat, these improvements did not appear to be directly linked to life extension. Interestingly, despite these metabolic benefits, the mice showed signs of biological stress , such as lower body temperatures and increased food seeking, which could make them more vulnerable to infection.
Fasting in humans
The findings from the mouse study raise questions about the effectiveness of fasting and calorie restriction in extending human life. According to Churchill and Di Francesco, “the dietary interventions used with mice in this study would not be tolerated by people.” Prolonged calorie restriction, even as low as 20 percent, or intermittent fasting for one day a week, may not be sustainable or practical in the long term. However, the question remains whether less extreme versions of these practices could still provide health benefits and potentially extend life in humans.