The effects of caloric restriction on health and longevity

There is increasing evidence that restricting caloric intake may have considerable health benefits in humans. Significant evidence in non-primate animals demonstrates that caloric restriction increases average and maximal life span. However, historically, caloric intake reduction in humans has been involuntary and accompanied by poverty, malnutrition, poor sanitation, and a lack of modern health care. As a result, caloric restriction in people typically has been accompanied by a reduction of both average and maximal life span. Conversely, improvements in standards of living usually are accompanied by an increased food supply and resultant improved health and longevity. The majority of the world is now in a new era where an abundance of caloric intake and its associated obesity are causing widespread chronic illness and premature death. What would happen if one were to institute caloric restriction with high-quality nutrition within an environment of modern sanitation and health care? This review argues that improved health and improved average life span would quite likely result. A lengthening of maximal human life span with this combination is perhaps possible but by no means certain.