Overweight teenage boys risk passing on harmful traits to future children, study suggests
People whose fathers were overweight as teenagers had DNA changes associated with asthma, obesity and low lung function.
A new study has investigated the long-term consequences of fathers’ early teenage obesity. It was led by researchers at the University of Southampton (UoS) and the University of Bergen.
They found boys who become overweight in their early teens risk damaging the genes of their future children. This puts them at greater risk of developing asthma, obesity and low lung function.
Researchers say the study highlights how failure to address obesity in young teenagers today could harm future generations.
Their findings have been published in Nature Communications Biology.
Investigating the impact
This is the first human study to reveal the likely biological mechanism behind the impact of fathers’ early teenage obesity on their children.
The researchers analysed data from 339 people. They were aged between seven and fifty-one.
They looked at the participants’ epigenetics - how a person’s environment affects the way their genes work, for example by switching them ‘on’ or ‘off’.
They also assessed the father’s changes in body composition across adolescence. To do this, they used self-reported body image as a proxy for body fat composition.
Changes to DNA
The research team identified epigenetic changes in over 2,000 sites in 1,962 genes. The genes are linked with formation of fat cells (adipogenesis) and fat (lipid) metabolism.
These changes in the way DNA is packaged in cells (methylation) regulate gene expression. They are associated with asthma, obesity and lung function.
The effect was more pronounced in female children than male children, with different genes involved.
Dr Negusse Tadesse Kitaba, Senior Research Fellow at UoS, authored the paper.
Dr Kitaba said: “The overweight status of future fathers during puberty was associated with a strong signal in their children’s DNA which were also related to the likelihood of their children being overweight themselves.
“Early puberty, when boys start their developing sperm, seems to be a key window of vulnerability for lifestyle influences to drive epigenetic changes in future offspring.”
Lifelong health consequences
Obesity is a major public health problem.
People living with obesity are at greater risk of many health diseases. These include type 2 diabetes, heart disease and some types of cancer. It may also have a negative effect on their mental health.
Prof John Holloway is a Professor of Allergy and Respiratory Genetics at UoS. He is also part of the NIHR Southampton Biomedical Research Centre.
Prof Holloway said: “Childhood obesity is increasing globally. The results of this study demonstrate that this is a concern not only for the health of the population now, but also for generations to come.”
Prof Cecilie Svanes is a Professor at the University of Bergen.
Prof Svanes added: “The new findings have significant implications for public health. They may be a game-changer in public health intervention strategies.
“They suggest that a failure to address obesity in young teenagers today could damage the health of future generations, further entrenching health inequalities for decades to come.”
The research was funded by the Norwegian Research Council.
Image credit: World Obesity Federation