Decades of research have shown that nutrition influences ageing and lifespan. A new study offers fresh insights, finding that mice on a calorie-restricted diet that maintained their weight lived longer, challenging conventional wisdom on the relationship between caloric intake and longevity.
Research conducted by The Jackson Laboratory and Calico Life Sciences has shed new light on the relationship between caloric intake and longevity. The study, using a mouse model, found that mice on a calorie-restricted diet that lost the least weight lived the longest.
Research published in Nature challenges conventional wisdom, suggesting that genetic factors, such as resilience, may be more influential in determining lifespan than dietary interventions.
The new study, recently published in the journal Nature, proposes that genetically encoded resilience may be a critical factor in extending lifespan, potentially outweighing the impact of dietary choices.
Examining caloric restriction and intermittent fasting
Researchers conducted a comprehensive study featuring 960 genetically diverse female mice investigated five diets:
• 60% or 80% daily caloric restriction
• Weekly fasting (one or two consecutive days)
• Ad libitum eating
However, scientists explored whether caloric restriction and intermittent fasting’s lifespan-extending effects apply universally or vary among individuals. To address this question, they utilized a genetically diverse mouse model.
Since its discovery in the 1930s, caloric restriction has been shown to extend rodent lifespan. Nonetheless, scientists continue to unravel the complex mechanisms behind this phenomenon. Meanwhile, new evidence suggests that optimizing meal timing can amplify the lifespan-extending effects of caloric restriction, revolutionizing our understanding of healthy ageing.
The findings of the research also indicate that caloric restriction’s effects on lifespan may be genotype-dependent. Our study examines whether caloric restriction’s benefits are universal and whether restriction severity (20% vs 40%) influences outcomes.
Losing weight may not extend longevity
Scientists sought to understand whether diet interventions like caloric restriction and intermittent fasting have universal benefits. Using a genetically diverse mouse model, they explored the complex relationship between diet and longevity.
According to researchers, Mouse studies showed genetics contributes substantially to lifespan. While diets like caloric restriction can extend life, individual variability underscores their limitations. Diets boost average lifespan but don’t ensure long life; other factors contribute equally.
Studies also revealed that mice with stable body weight, body fat percentage, and immune cell health during caloric restriction and stress lived longer.
Caloric restriction’s impact on lifespan extension in mice may be linked to its effectiveness in reversing obesity and prediabetes traits, supporting the notion that optimal metabolic health is essential for a long and healthy life, as per the study
“Mice retaining higher body weight experienced greater lifespan extension, revealing that weight loss isn’t the primary mechanism. Caloric restriction yields separate outcomes: weight loss and lifespan extension,” said the lead authors of the study.
Research translation to humans needed
According to Dr. Mir Ali, Medical Director of MemorialCare Surgical Weight Loss Center, a study revealed that eating less can extend lifespan, challenging the conventional wisdom that weight loss is the primary factor.
“While animal studies show caloric restriction extends lifespan, separate from weight loss, applying these findings to humans is challenging. More research is needed to confirm translation,” Ali continued.
Monique Richard, a registered dietitian nutritionist, finds the study’s results consistent with the current understanding of how lower-calorie diets, fasting, and eating pattern adjustments enhance cellular function.
Tips for improving aging and longevity
While genetics contribute to longevity, lifestyle adjustments can promote healthier ageing. Learn how diet, exercise, and other options can support well-being and potentially extend lifespan.
“Your genetics lay the foundation for longevity, but lifestyle decisions can either support or undermine it,” Dr. Ali noted. “Avoiding obesity and unhealthy eating habits is crucial to aligning your choices with your genetic blueprint. A healthy genetic makeup is just the beginning. To reach your full potential, prioritize whole foods, exercise, and weight management,” he said.
“Our bodies constantly adapt to maintain a state of optimal balance – running smoothly and efficiently,” Richard detailed. “With essential nutrients, cellular processes hum along, systems working in tandem. This optimal balance sparks peak performance, increasing the likelihood of extended lifespan and enhanced overall well-being.”
