How and why does calorie restriction provide health benefits if started late in life? EurekAlert! notes work on these and related questions: "Much research has shown that reduced calorie intake can increase health and longevity. Professor Stephen Spindler [and] his collaborators have discovered that reducing calorie intake later in life can still induce many of the health and longevity benefits of life-long calorie reduction. Importantly, this also includes anti-cancer effects. They are using this knowledge to establish a novel screening technique to find drugs which mimic this longevity effect. ... Physiological changes associated with ageing include cell damage and the emergence of cancer cells. The most important effects of low calorie diets and longevity therapeutics given late in life may not be to prevent this damage, but instead to stimulate the body to eliminate damaged cells that may become cancerous, and to stimulate repair in damaged cells like neurons and heart cells. Low calorie diets drive the body to replace and repair damaged cells. This process usually slows down as we age, but low calorie diets make the body re-synthesise and turn over more cells - a situation associated with youth and good health."