Men who were overweight at 18 are a third more likely to die from cancer in middle age, a new study suggests.
Researchers claim that the risk remains even among those who lose weight later in life.
The findings come in a study of the medical records of 20,000 men who attended the prestigious Harvard School of Public Health between 1916 and 1950.
Lead researcher Dr Linsay Gray, of the Medical Research Council, said: “This is the first time the impact of obesity in early adulthood on later risk of cancer has been so closely examined.
“The message here is really clear: keeping your weight healthy as a young adult can significantly reduce your chance of developing cancer. These findings point worryingly to a greater future burden of cancer.”
In a paper to be published in the Annals of Oncology, the researchers describe how the students with the highest Body Mass Index – a figure based on an individual’s height and weight – at age 18 were 35 per cent more likely to die from cancer later in life than those who were thinner.
Those who were overweight or obese as teenagers were 50 per cent more likely to die of lung cancer than those who were a healthy weight, regardless of whether or not they smoked.
Weight loss between early adulthood and middle age did not affect the risk.