Men, if you have been looking for yet another reason to finally get into shape, try this one: Your obesity may increase your daughter's risk for breast cancer.

Do we have your attention now?

Researchers at the Department of Oncology at Georgetown Lombardi Comprehensive Cancer Center in Washington, D.C. have found evidence that obesity alters the epigenetic regulators of gene expression in both the dad's sperm and the daughter's breast tissue. In short, there's a direct connection between obese fathers and their daughter's breast cancer risk.

Medicine has known for a while that a mother's lifestyle – diet and smoking, for instance – could lead to gene mutations she could pass along to her children, but until this study, the fathers had gotten a pass. The scientists have published their data in Scientific Reports.

The epigenetic regulators identified control insulin receptor signaling, which is linked to alterations in body weight, and other molecular pathways that are associated with cancer development such as the hypoxia signaling pathway.

"This study provides evidence that, in animals, a fathers' body weight at the time of conception affects both their daughters' body weight at birth and in childhood as well as their risk of breast cancer later in life," says the study's lead investigator, Sonia de Assis, PhD, an assistant professor in the department of oncology at Georgetown Lombardi.

"Of course our study was done in mice, but it recapitulates recent findings in humans which show that obese men have significant epigenetic alterations in their sperm compared to lean men. Our animal study suggests that those epigenetic alterations in sperm may have consequences for next generation cancer risk."

de Assis says the next step in this research is to see if the same associations regarding breast cancer risk hold for daughters of human fathers who are overweight around the time of conception.

"Until we know about this association in men, we should stick to what we all know is good advice: women -- and men -- should eat a balanced diet, keep a healthy body weight and life-style not only for their own benefit but also to give their offspring's the best chances of being healthy."