Fathers who eat a high-fat diet may be bad news for their daughter's health.
This study was done using rats and such studies are difficult to conduct in humans because it is hard to control other environmental factors.
"If it is true in humans, then it may be potentially contributing to what seems to be the amplification of the obesity and diabetes
epidemic," said Margaret Morris, senior author of the study, which was published in the journal Nature Thursday.
Studies in the past found that a pregnant woman's body weight and state of health affect her foetus, but this study suggests the father's health and lifestyle may also be important.
"The take home message is we have to consider that metabolic health, fitness, blood glucose and weight of both mother and father at the time of conception have the potential to impact on the health of the offspring," said Morris of the pharmacology department at the University of New South Wales in Sydney.
"Fathers have been advised to stop smoking and consume less alcohol
around conception but maybe the advice ought to go stronger than that in terms of maintaining a healthy body weight and diet," she said by telephone.
Led by Ng Sheau Fang at the University of New South Wales, the study used male rats that were genetically similar. Half were fed a high-fat diet, the other half a normal diet, and the first group ended up obese and diabetic.
They were all paired with healthy, non-diabetic female rats of normal weight and female offspring of the obese and diabetic rats began showing signs of diabetes by week 13.
Morris said the outcome may be attributed to non-genetic "environmental factors."
"The only difference here is that the sperm was influenced by the environment and hormonal and metabolic change in the (obese and diabetic) father. But that somehow is being transmitted to the offspring and into their pancreas," Morris said.
"One possibility has to be that it altered the sperm ... in motility, some increased risk of DNA damage," she said.Do you look after yourself as a parent? Did you know it could affect your children if you didn't?