New evidence suggests that fathers may influence their children’s obesity risk through changes in sperm, lifestyle habits, parenting behaviors and the family environment, prompting researchers to call for inclusive strategies that start even before conception.
Study: The Role of Fathers in the Intergenerational Transmission of Obesity. Image credit: Creativa Images/Shutterstock.com
A recent review published in the magazine Current obesity reports suggests that fathers influence obesity risk in their children through multiple interactive pathways that begin before conception. The findings suggest that childhood obesity prevention and research efforts should focus on both fathers and mothers.
Expanding obesity research beyond maternal factors
Childhood obesity continues to rise in the United States alongside rising rates of overweight and obesity among adults. Current projections show that more than 250 million Americans could be overweight or obese by 2050.
Research shows that children are more likely to develop obesity when one or both parents are affected, particularly when both parents are obese. This relationship highlights the complex interplay of genetic, biological, behavioral, and environmental factors that contribute to intergenerational obesity risk.
According to the Developmental Origins of Health and Disease (DOHaD), the periconceptional period is critical for setting the stage for future long-term outcomes, including cardiometabolic disease, through exposure to environmental factors. Maternal nutrition, obesity, and metabolism have been studied in detail because they shape the fetal environment.
More recently, the Paternal Origins of Health and Disease (POHaD) framework was brought under the DOHaD umbrella. The current review examined biological, psychological, and behavioral pathways through which paternal factors influence children’s health, although not in isolation from family dynamics and other environmental and social factors. The authors emphasize that paternal influences operate alongside maternal and extended family influences.
Obesity alters sperm and offspring metabolism
About 40% to 70% of obesity is inherited through hundreds of obesity-linked variants. Paternal obesity affects offspring metabolic health in several ways.
Paternal obesity affects sperm quality, reduces sperm concentration and motility, and increases the rate of sperm DNA fragmentation. These changes are associated with the adverse effects of obesity on paternal metabolism. These sperm abnormalities are reflected in a 30% to 66% increase in the risk of infertility in men with obesity and increase the risk of pregnancy loss unrelated to maternal factors.
Obesity is associated with metabolic dysregulation through disrupted endocrine regulation of sperm production. testicular inflammation and systemic; and epigenetic alterations in sperm. Sperm are continuously produced and mature for months before conception, allowing for a wide window of environmental exposure.
Changes in the epigenetic profile are heritable and affect gene expression in the developing fetus in pathways linked to appetite regulation, insulin signaling and fat metabolism. In animals, a high-fat diet in the father is associated with obesity-related changes in the offspring. However, while animal studies provide strong evidence for these mechanisms, the biological pathways in humans remain poorly understood.
Specifically, some epigenetic changes in sperm associated with obesity are reversible with lifestyle modifications prior to conception.
The habits of fathers help shape the behavior of children
Fatherhood tends to be associated with weight gain in fathers and changes in multiple health behaviors, for better or worse. A healthy paternal diet before conception is associated with improved sperm quality and concentration, independent of age and body mass index (BMI). The reverse is true with a poor quality diet.
The quality of the father’s diet, physical activity habits, feeding practices and parenting style directly and indirectly, through role models, influence the child’s nutrition and activity levels. This also happens with physical activity and sedentary habits in the father.
Positive modeling, monitoring, and shared family meals are associated with better diet quality and healthier food choices in children.
Neighborhood and access to food shape outcomes
The risk of paternal obesity is influenced by many other factors, including income, education, and type of neighborhood.
Residential neighborhood affects children’s nutrition, directly through access to food and indirectly through its association with food security, socio-economic status and father’s mental health. Food insecurity is associated with greater consumption of high-calorie foods and an increased risk of obesity. Similarly, limited access to safe recreational spaces limits physical activity and increases the risk of obesity.
Such factors operate at the family level, affecting multiple domains, ranging from the father’s physiology and parenting to the child’s developmental environment. These interact to exacerbate the intergenerational increase in obesity risk.
Mental health is especially important. If the father is depressed, he is less likely to have an engaged or positive parenting style or to value preventive health care for himself or his family. This worsens children’s eating and sleeping behaviors and increases the risk of obesity. Children who live with a parent experiencing depression are at increased risk of adverse childhood experiences (ACEs), which may influence long-term obesity risk.
Fathers may influence obesity risk early on
The authors conclude that fathers play an important role in how obesity risk is transmitted between generations. This begins before conception and continues into childhood. However, the authors note that much of the current evidence is observational, and additional human research is needed to better understand the biological mechanisms linking paternal health and offspring obesity risk.
They suggest that obesity prevention strategies should include preconception counseling aimed at fathers as well as mothers. perinatal education targeting both parents; including fathers in obesity prevention methods; workplace policies that promote father involvement in child care; and placing greater emphasis on research examining the role of fathers in the intergenerational transmission of obesity.
