The regulatory functions of vitamins are described with particular reference to their importance in the metabolic processes of ageing. Although clear hypovitaminosis is uncommon, slight vitamin deficiencies are often encountered in the clinical practice. They cause a speed up of the organism deterioration. The nutritional requirement and the effect of vitamin A, B1, B6, B12, are rapidly reviewed. More attention is paid to the data about vitamin C, D and E. Vitamin C deficiency in elderly, especially in the hospitalized ones; whereas a high content of ascorbic acid in necessary in order to extend the life length and to achieve a good self-sufficiency. Also the deficiency of vitamin D and of its metabolites is frequent in the aged due to both a lower uptake and a scarce exposure to the sunlight. Low levels of vitamin D cause a worsening of bone tissue and consequent demineralization (osteomalacia and osteoporosis). Some aspects of ageing can be prevented by the supply of vitamin E, particularly the impaired bone trophism. The anti-oxidant power of tocopherol could also interfere some pathogenetic processes of ageing.