A large study involving nearly 1,000 mice challenges conventional wisdom about how dietary restriction increases longevity. While calorie-restricted diets and intermittent fasting did cause weight loss and metabolic changes in mice, other factors like immune health, genetics, and physiological resilience better explained increased lifespan. Surprisingly, the mice that lost the most weight on calorie-limited diets tended to die younger than those with modest weight loss.
In conclusion, the study suggests that processes beyond simple metabolic regulation drive the body’s response to limited-calorie regimens, with immune health, red blood cell function, and overall resilience being key factors. These findings could reshape how scientists approach studies of dietary restriction in humans and highlight the need to look beyond metabolic measurements when assessing potential life-extending strategies.