Severe dietary restriction delays the physical development of rodents and leads to adult animals of reduced body size but significantly increased life expectancy. We tried to find a similar relationship in human populations using demographical and statistical methods. We show for the total Spanish male population that the mean adult body height reliably reflects the regional living and nutritional conditions. This relation does not only hold for todays socioeconomic data but can also be reproduced using data on family income in the mid 19th century. We calculated the mean height of young men liable to the military service around 1860 and determined their longevity retrospectively using posterior census data. This was done separately for all the Spanish provinces. The linear regression between both parameters manifests a statistically highly significant relationship: the smaller the mean height at age 18 in a province, the higher the chance for people living there to reach high chronological ages. Migrational movements, selection, mortality due to epidemics or unreliability of the population censuses can be largely ruled out as explications for the described correlation. Furthermore, we determined the secular growth trend in Spain for the last 130 years. From 1860 to 1920 the mean height increased by 2.7 cm, from 1920 to 1987 by another 9.8 cm. Since 1950 the trend is above 2 cm per decade country-wide. From 1974 onwards it amounts to 2.89 +/- 0.17. Such high values were worldwide looked upon as isolated cases found only in geographically and socially isolated population subgroups during very limited periods.