The lifestyle of parents - rather than their genes – is mainly responsible for their children being overweight, say researchers.
A new study of adoptive children shows inherited factors are far less important in creating weight problems than the environment where they grow up, including the parents' diet and exercise habits.
The researchers compared the bodyweight of thousands of biological and adopted children to that of their parents.
They found that when both adoptive parents are overweight, the likelihood of an adopted child being overweight is up to 21 per cent higher than when the parents are not overweight.