Rat Grandmas' Diet Linked to Granddaughters' Cancer

A high-fat diet consumed by female rats was associated with a greater risk of breast cancer in her next two generations of female progeny, who ate a normal diet. Cynthia Graber reports

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How’s this for a possible new culprit for breast cancer sufferers: they may be able to blame their grandmas’ diets. That’s the implication of a study done with rats. Researchers [Sonia de Assis et al.] affiliated with the Georgetown University Medical Center fed a group of pregnant rats a high-fat diet throughout their gestation, with 43 percent of calories coming from fat. A control group ate a normal diet. Both groups consumed the same total calories. All the rats’ offspring and the next generation, the granddaughters, ate a normal diet.

That high-fat diet increased breast cancer in the rats’ female offspring. And, more surprisingly, it apparently increased breast cancer in the granddaughters. They had an 80 percent chance of developing the disease, compared with 50 percent in the control group. The results were presented at the meeting of the American Association for Cancer Research.

Researchers theorize that the high-fat diet may change gene expression in the grandmothers in a way that somehow affects subsequent generations and leads to a greater breast cancer risk. The scientists say this may mean that pregnant moms should eat well not only for the health of their offspring but for future generations as well.


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—Cynthia Graber

[The above text is an exact transcript of this podcast.]

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