Proceeding from experiences with animal-experimental studies is tried to show all those mechanisms which have influence on the ageing process of man. In these cases in the experimental part of the study is particularly investigated the influence of the restriction of food in obese patients on the cardiovascular system, the lipid metabolism and the biological age. In obese patients of middle age by isocaloric reduction diet a normalisation of the at present changed non-invasive cardiodynamic parameters could be achieved. Apart from a normalisation of cholesterol and LDL-cholesterol, however, a decrease of the HDL-cholesterol of the same intensity was found. The biological age could be influenced under restriction of food. To what extent overweight and food restriction in man closely correlate with the life expectancy remains the subject of further investigations.