"We know that poor diet and defective genes can both affect development, but here we have seen the two combine to cause a much greater risk of developing health problems and more severe problems. We are excited by this as it suggests that congenital heart defects may be preventable by measures such as altering maternal diet."

"There is a growing amount of research which suggests that a mother's diet can have a long term impact on the health of her offspring," says BHF Professor Shoumo Bhattacharya. "This is concerning when we also consider the increasing problem of obesity in women of reproductive age. A healthy, balanced diet is important at all times, but our research shows that this is particularly true during pregnancy when diet can potentially affect both the mother and her child."

Professor Jeremy Pearson, Associate Medical Director of the BHF, which part-funded the study, said:

"This research shows that diet during pregnancy can directly affect which genes get switched on in unborn offspring. The study was with mice, but a similar link may exist in humans, leading to some cases of congenital heart disease.

"We already know that if pregnant women lack certain nutrients in the diet, such as folic acid, it can lead to abnormal development in the baby, so it's not surprising that eating too much of something can also cause problems.

"The findings suggest it's wise for pregnant women to stick to a balanced diet and avoid eating too much fatty food. This is good advice for everyone, especially mothers and their children."

Source: Wellcome Trust