The Fitness Zone
The detrimental effects of maternal obesity on offspring has been the clear focal point for many recent investigations, however it seems Dad's the word according to a new study.
Paternal Impact On Female Offspring
A recent PhD study, supervised by Professor Margaret Morris of the School of Medical Sciences at the University of New South Wales, revealed that female offspring of obese male rats developed the same glucose intolerance as their fathers.
“In mothers, there are clear mechanisms where that might happen through the uterus. What happens while a foetus is developing can have an impact,” Morris said, “but the father has really been a bit of an untapped question.”
In the study, male rats were fed on a diet known to cause obesity and diabetes, ten weeks before they were allowed to mate. When they were mated, they were obese, they had increased insulin and they were glucose intolerant: “diabetic, if you will,” said Morris.
The females developed glucose intolerance at six weeks, which got worse at twelve, demonstrating abnormalities in the genes of pancreatic cells which produce insulin. The most intriguing finding of this investigation, however, was that although the females became glucose intolerant at a young age, they were not obese.
One question that remains, of course, is whether the obesity may develop as they age. “That's the subject of ongoing work,” concluded Morris.
Paternal Impact On Male Offspring
In further studies at the Garvan Institute of Medical Research and the Victor Chang Institute, it was shown that obese male rats passed on a predisposition to metabolic diseases to both their sons and grandsons. Grandsons were susceptible to this predisposition even if their fathers were healthy at the time of conception. When fed a high fat, high sugar diet, the offspring quickly developed signs of fatty liver disease and pre-diabetic symptoms. It was noted that symptoms were still present, but significantly reduced in great-grandsons.
It is possible that changes in RNA (ribunucleic acid) in sperm lead to these results, and that the same results could occur in humans. Implications of these findings are that if your father or grandfather were overweight, you may need to be particularly mindful of pursuing your fitness and a healthy diet in order to maintain a healthy weight. If you are considering fatherhood, there is an incentive to achieve a healthy weight before conception.
Similar studies at Georgetown University have shown that children fathered by obese men are at a higher risk of diabetes, abnormal metabolism and certain cancers. Conversely, the children and even grandchildren of men who had a lack of food as children are less likely to have heart disease and diabetes.
Earlier studies focused on the impact of maternal obesity on the health of children, while it is now evident that the impact of male obesity also needs to be considered. This research is important to the future health of Australians, as 63% of Australian adults are overweight or obese, with many of these in their childbearing years. This is a ten percent increase from levels in 1995. 25% of Australian children are overweight. Being overweight or obese is the second highest contributor to the burden of disease in Australia, with dietary risks coming in at number one.
Danish researchers have discovered that cells in sperm affecting the appetite of offspring can differ between lean men and obese men. Sperm takes two months to develop, so any improvements need to be made this amount of time before conception. The good news is that any improvement, no matter how great or small, will start making a difference.
It’s also important to note that childhood health is a product of both genetics and environment. The habits you teach your children can have a significant impact on the expression of the genes they have inherited from you. Many behaviours that influence lifelong health are established during early childhood, including eating habits, activity levels and sleeping patterns. In fact, childhood obesity is increasing at a rate exceeding the speed of genetic mutation. Other factors to consider are that food preferences are established in the womb, and breast feeding rather than formula feeding can also reduce the risk of childhood obesity.
Taking Steps To Ensure Healthy Children
The link between parental obesity and childhood health could highlight the possibility of a cycle that will be hard to break. The role of fitness and health professionals is becoming increasingly important and popular in managing the health of the nation, not just for the current generation but for those to come as well. When working with children, it is important to tailor programs to suit their age, size and capabilities, and it can be beneficial to get the whole family involved.
To find out more about about fitness courses with the Australian Institute of Fitness.