A groundbreaking study published in Nature has revealed that a consistent lower caloric intake significantly outperforms periodic fasting in extending lifespan. The research, conducted by scientists at Researchers at The Jackson Laboratory (JAX), involved nearly a thousand genetically distinct mice on various dietary regimens.
The study challenged existing theories on the biological markers of ageing and longevity. Previous research had suggested that periodic fasting could be as effective as reducing overall caloric intake. However, the new findings indicate that maintaining a consistently lower caloric intake is more beneficial.
The authors of the study wrote that caloric restriction extends healthy lifespan in multiple species. Intermittent fasting, an alternative form of dietary restriction, is potentially more sustainable in humans, but its effectiveness remains largely unexplored. Identifying the most efficacious forms of dietary restriction is key for developing interventions to improve human health and longevity.
As per the study, the researchers performed an extensive assessment of graded levels of caloric restriction (20% and 40%) and intermittent fasting (1 and 2-day fasting per week) on the health and survival of 960 genetically diverse female mice. They show that caloric restriction and intermittent fasting both resulted in lifespan extension in proportion to the degree of restriction.
Lifespan was heritable, and genetics had a larger influence on lifespan than dietary restriction. The strongest trait associations with lifespan included retention of body weight through periods of handling-an indicator of stress resilience, high lymphocyte proportion, low red blood cell distribution width, and high adiposity in late life.
