How boys grow determines how long they live

Objectives: Increase in height in modern societies has been accompanied by an in increase in lifespan. The longer lives of taller people suggest that good nutrition during childhood, together with freedom from recurrent minor infection, prolong human life. There is, however, a caveat. Tall adult stature may be the result of rapid "compensatory" growth following a setback. Compensatory growth is known to reduce the lifespan of animals, possibly because it is disorganized. Methods: We analyzed lifespan among 6,975 men born in Helsinki, Finland, during 1934-44. Their early growth was recorded. Results: Boys who were tallest at seven years of age had lower all cause mortality, the hazard ratio being 0.79(95%CI 0.70 to 0.89, P < 0.0001) per 10 cm increase in height. There was, however, a group of boys among whom being tall was associated with increased all cause mortality, the hazard ratio being 1.32(1.00 to 1.75, P = 0.05). These boys were taller at seven years than their birthweight and length at birth predicted. After they were excluded from the analysis, boys who were more than 126 cm in height at seven lived for eight years longer than those who were 114 cm or less. This increase in lifespan was similar to the effect of high socio-economic status in adult life. Conclusions: Rapid growth in childhood height usually predicts a longer life. But tallness among men may be a misleading indicator of wellbeing and longer life expectancy in populations where compensatory growth is widespread. African Americans may be an example.