‘Dad bods' may influence childhood obesity risks

Irvine, Calif., June 4, 2026 - As obesity rates rise across the U.S., new research from Joe C. Wen School of Population & Public Health at the University of California, Irvine scientists draws attention to an often-overlooked factor in children's long-term health: fathers.

Published in Current Obesity Reports, the review examines how a father's health before and during parenthood-including obesity, diet, stress, mental health and lifestyle habits-can influence a child's risk for obesity and related health conditions, even before conception. The findings suggest that what is often dismissed as a "dad bod" may reflect health factors that can shape children's long-term well-being, or in other words, not as harmless as it may seem.

"We found that fathers' health as an important contributor to children's health through biological, behavioral and environmental pathways," said corresponding author Matthew Landry, assistant professor of population health & disease prevention and a registered dietitian nutritionist.

Current trends indicate that more than 250 million people in the U.S. will be overweight or obese by 2050, according to estimates cited by the researchers. While maternal health has long been the focus of efforts to understand childhood obesity, this study and other evidence suggest fathers also play a meaningful role in shaping children's health.

"Obesity is not simply the result of individual choices," Landry said. "This work highlights that obesity risk is 40 to 70 percent heritable and can be passed across generations through complex biological and environmental influences."

Recent evidence collected in this review suggests that obesity can affect sperm quality and alter epigenetic markers - biological signals influenced by behaviors and environment that help regulate how genes function during early development. These changes can potentially affect appetite regulation, metabolism and long-term disease risk in children.

Encouragingly, though, there is evidence that suggests these effects may be reversible. Weight-loss interventions, including lifestyle changes and bariatric surgery, can improve sperm health and modify obesity-related epigenetic patterns, according to the researchers.

Beyond biology, fathers help shape family routines and behaviors that influence children's health. Fathers' eating habits, physical activity levels and approaches to parenting are closely associated with children's diet quality, activity levels and obesity risk. Active involvement in meal preparation, eating meals together and shared physical activity has been linked to healthier outcomes for children.

The review also highlights the broader factors that affect fathers' ability to support healthy lifestyles, including income, food insecurity, neighborhood conditions, workplace policies and mental health.

The authors argue that healthcare systems and public health programs should include fathers in obesity prevention efforts to a greater degree. Recommendations include father-inclusive prenatal care, expanded support for paternal mental health, paid parental leave and flexible workplace policies that support family well-being.

"Fathers have historically been overlooked in maternal and child health research and intervention efforts," Landry said. "Recognizing fathers as active contributors to family health creates new opportunities to improve outcomes for future generations."

The researchers conclude that addressing obesity requires a family-centered, multigenerational approach - one that recognizes fathers as essential partners in building healthier futures for children.

The research was supported by an American Heart Association Career Development Award to Landry. Co-author John James Parker is an assistant professor of pediatrics at Northwestern University Feinberg School of Medicine.

About the University of California, Irvine: Founded in 1965, UC Irvine is a member of the prestigious Association of American Universities and is ranked among the nation's top 10 public universities by U.S. News & World Report. The campus has produced five Nobel laureates and is known for its academic achievement, premier research, innovation and anteater mascot. Led by Chancellor Howard Gillman, UC Irvine has more than 36,000 students and offers 224 degree programs. It's located in one of the world's safest and most economically vibrant communities and is Orange County's second-largest employer, contributing $7 billion annually to the local economy and $8 billion statewide. For more on UC Irvine, visit www.uci.edu.

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