Abstract Caloric restriction (CR) in normal human bodies means to maintain a low-caloric diet, balanced in nutrients, vitamins and catalytic mineral ions (ca. 1750 Kcal/day), in order to benefit aging in good health, an active longevity preventing emerging diseases, and avoiding not genetic but certain kinds of obesity. A correct caloric intake for the energy needs of the human body for normal activity is necessary. Every organism has a particular metabolism that depends on its genetic and epigenetic characteristics, diet and habits (activity, stress, and toxics) and we must adapt its diet, hoping to enjoy good health and achieve an active longevity. Food that we consume our body metabolizes, excretd or accumulated. If it is too much can be stored in the form of fat. The excess of diet leads to cell damage and shortening of life. The mitochondria is like a metabolic turbine of energy production, and eliminates the last steps of nutrients as CO2 and H2O. It’s functioning and its good physiological condition is cause of longevity. In humans, caloric restriction (CR) is beneficial, and prevents a long list of diseases of the elderly, which we quote in the text. It protects against the causes of aging, prevents production of free radicals, and the accumulation of fat and damage.