Why children of obese fathers are prone to weight gain, by study

• Overweight expectant mothers at risk of damaging their baby’s heart’
• Breastfeeding slashes woman’s risk of diabetes by 20%
A man’s weight affects the heritable information contained in sperm, according to a study published in Cell Metabolism. This could help explain why children of obese fathers are more likely to suffer from obesity.

Obesity is a metabolic disorder resulting from behavioral and heritable causes. Children of obese fathers more frequently develop metabolic diseases later in life, regardless of the mother’s body weight.

This suggests that obesity and related conditions could stem from the father, supporting the findings of previous rodent studies.

Senior author Romain Barrès, an associate professor at the University of Copenhagen in Denmark, was inspired by a previous study in which the availability of food to people during a famine correlated with the risk of their grandchildren developing cardiometabolic diseases.
That study indicated that the nutritional stress of the grandparents was probably passed down through epigenetic marks.

These can be chemical additions on protein that wrap up Deoxy ribonucleic Acid (DNA)/genetic material, methyl groups that change the structure of DNA once attached or molecules called small Ribo Nucleic Acids (RNAs).
Epigenetic marks can control how genes are expressed, and they have been seen to affect the health of offspring in insects and rodents.

Barrès and colleagues compared specific epigenetic marks in the ejaculate of 13 lean and 10 obese men.
Sperm cells of lean and obese men were found to possess different epigenetic marks, especially in regions associated with appetite control.

While no differences were seen in the proteins that wrap up DNA, there were variations between the participants’ small RNAs, as well as methylation of genes associated with brain development and appetite. The function of the RNAs is not yet determined.
To find out whether these differences were byproducts of obesity, the researchers looked at the effect of bariatric surgery on sperm epigenetics. They tracked six men undergoing weight-loss surgery to study the impact on their sperm.

An average of 5,000 structural changes to sperm cell DNA were observed before the surgery, directly after and one year later, indicating that weight is the main factor.

The findings suggest that sperm carries information about a man’s health, but more research is needed to establish the meaning of these differences and their effects on offspring.

Barrès says: “Our research could lead to changing behavior, particularly pre-conception behavior of the father. It is common knowledge that when a woman is pregnant she should take care of herself, not drink alcohol, stay away from pollutants, and so on; but if the implication of our study holds true, then recommendations should be directed towards men, too.”

Meanwhile, pregnant women who are obese risk a myriad of health problems afflicting their unborn baby. From diabetes to weight problems, scientists have long argued the dangers of women conceiving while they are overweight.

But now, a new study has added another concern to that list. A New York-based cardiologist has warned obese expectant mothers, and those with diabetes, risk causing damage to their baby’s hearts.
The research was presented at EuroEcho-Imaging 2015, the annual meeting of the European Association of Cardiovascular Imaging, a branch of the European Society of Cardiology in Seville last week.

Dr. Aparna Kulkarni, a paediatric cardiologist from the Bronx, said changes in foetal hearts have been detected in these groups of pregnant women.

She said: “The main concept behind this study is of foetal programming. This refers to changes that occur in the structure and physiology of tissues in the foetus as a result of the mother’s health. Diabetes and obesity are major epidemics of the present century.
“I see a lot of mothers with one or both conditions in my clinical practice and wanted to investigate if these maternal conditions had any effect on the foetal hearts.”

Also, a major study has found breastfeeding cuts a woman’s risk of getting diabetes by a quarter.
Not only that, it also reduces her baby’s chance of developing the condition in adulthood by almost a fifth.
Researchers believe breastfeeding uses up excess fat and sugar in a mother’s body helping protect her from diabetes.
Furthermore, babies given breast milk are far less likely to become obese, which is strongly linked to the condition.

The Canadian scientists say their findings are yet further evidence of the numerous health benefits of breastfeeding for women and their babies.
Professor Gary Shen, of the University of Manitoba, analysed the records of 334,553 babies born over a 24-year period in that region.

He also studied whether the mothers had breastfed for any length of time and if they or their children had later developed diabetes.
The results showed that women who had started breastfeeding were 23 per cent less likely to develop diabetes over the 24-year time frame. Their babies were also 18 per cent less at risk compared to children who had been given formula milk.

Shen, who presented the findings this week at the World Diabetes Congress in Vancouver, is unsure of the exact explanation but there are several possible causes.
One is that breastfeeding uses up a woman’s excess fat and sugar, which can trigger type 2 diabetes. It also prevents obesity – which is strongly linked to the condition – and burns between 200 and 500 calories a day. Babies who are breastfed are also less likely to become obese – as breast milk is less rich than formula milk and so they do not drink as much.