WASHINGTON — Researchers have long thought there is a link between a woman’s weight when she becomes pregnant and the health of her child.

Now, they are beginning to look at dads.

Researchers at the Georgetown Lombardi Comprehensive Cancer Center conducted a study in mice and found that if a father is obese at the time of conception, his daughter could be at greater risk for breast cancer.

Sonio de Assis, an assistant professor in the department of oncology at Lombardi, was the lead author of the study.

“Our study provides evidence that, in a mouse model, a fathers’ body weight at the time of conception affects their daughter’s body weight and likely also their risk of getting breast cancer later in life,” Assis says.

The female mice of obese fathers tend to grow up with an increased number of what scientists call “terminal end buds” in their breast tissue. That’s the site were cancer often develops in rodents.”

Of course, it is a big leap from mice to humans, and de Assis warns that much more study is needed. But in the meantime, she says “everyone — both men and women — should eat a balanced diet, not only for their own benefit, but also to give their offspring the best chances of being healthy.”

The Georgetown research team will formally report its findings on Tuesday at the annual meeting of the American Association for Cancer Research.

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