Occurrence and timing of childhood overweight and mortality: findings from the Third Harvard Growth Study

To assess the mortality experience of participants in the Third Harvard Growth Study (1922-1935) who provided ≥ 8 years of growth data.

A total of 1877 participants provided an average of 10.5 body mass index measurements between age 6 and 18 years. Based on these measurements, the participants were classified as ever overweight or ever >85th percentile for height in childhood. Age at peak height velocity was used to indicate timing of overweight relative to puberty. Relative risks of all-cause and cause-specific mortality according to measures of childhood growth were estimated using Cox proportional hazards survival analysis.

For women, ever being overweight in childhood increased the risks of all-cause and breast cancer death; the risk of death from ischemic heart disease was increased in men. Men with a first incidence of overweight before puberty were significantly more likely to die from ischemic heart disease; women in the same category were more likely to die from all causes and from breast cancer.

We find evidence of long-term effects of having ever been overweight, with some evidence that incidence before puberty influences the pattern of risk.