While the existence of age-related Mg deficiency is difficult to prove, intake of Mg by old people tends to be suboptimal, and the finding of decreased intestinal Mg absorption with progressive age provides evidence for the fact that the Mg requirement may be higher in elderly people than young adults. Chronic diseases, such as diabetes, congestive heart failure and alcoholism, common among elderly people, may further contribute to Mg depletion. A number of the drugs used in aged patients are also known to promote Mg loss. On the other hand, long-term Mg deficiency may play a role in the aging process, by affecting neurotransmitter activity, hormone synthesis and immune function, and/or may enhance cardiovascular disease, which is the most common cause of morbidity and mortality in old age. Despite this type of evidence, there is a lack of data concerning the effects of Mg supplementation in the aged.