The BBC reports: A high-fat diet during pregnancy has the potential to alter a baby's developing brain and increase its chances of obesity later in life, animal studies suggest.
The team at Yale School of Medicine, in the US, showed diet could change the structure of mice brains.
They argue this could explain why the children of obese parents are more likely to become grossly overweight.
Experts said the study had merit, but brain changes in humans were unproven.
Obesity can run in families and shared eating habits are a major factor.
However, there is evidence that diet during pregnancy can also influence a child's future waistline, such as through changes to DNA.