In 1946 a British study began tracking a cohort of British newborns. The study's participants are now 65. Helen Pearson reports on the findings:

It has shown that the heaviest babies were most at risk of breast cancer decades later; that children born into lower social classes were more likely to gain weight as adults; that women with higher IQ reached menopause later in life; and that young children who spent more than a week in hospital were more likely to suffer behaviour and education problems later on.

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