Can eating well-cooked meats raise a woman’s risk of getting breast cancer? A decade worth of science has yet to provide conclusive results.
In 1998, a team of researchers at the University of Southern California, lead by Wei Zheng, M.D., Ph.D., found that women who eat well-cooked meats were four times more likely to have breast cancer. Over cooking meats by frying or grilling can create carcinogenic compounds called heterocyclic amines (HCAs), which have been linked to some cancers, including stomach and colorectal.
Although Zheng’s study was relatively small (only 273 breast cancer cases were included), the results were intriguing. Heterocyclic amines had been shown to produce mammary cancers in laboratory rats, but few studies had looked at the compounds in humans.
Zheng’s findings, however, were soon contradicted. In 2000, a UC Irvine College of Medicine study found that well-done red meat does not appear to increase a women’s risk of breast cancer. The researchers found no significant associations of breast cancer with red meats at any level of doneness.
Well, which is it?
“We have published a number of papers since then (1998) showing that some genetic factors may modify the association of HCA exposure and breast cancer risk,” writes Dr. Zheng, now at Vanderbilt University Medical Center. “But the studies are small and results inconclusive.”
Although the relationship between HCA’s and breast cancer has yet to be clarified, it does not mean there isn’t one. Instead, it may mean the relationship is more complex than originally thought.
One of the complexities that Zheng is studying is polymorphisms, or genetic changes that vary across a population. Genetic polymorphisms can affect how a person metabolizes heterocyclic amines and may therefore need to be taken into account when trying to find out if well-cooked steaks and pork chops increase one’s risk of breast cancer.
In addition, heterocyclic amines may not be the only toxic compound found in well cooked meats.
“The assumption is that heterocyclic amines are the causal agents in these meats; however, a variety of different types of genotoxic compounds are potentially present in grilled meats,” notes Robert Turesky, Ph.D., research scientist and Associate Professor at the New York State Department of Health.
Other researchers are looking at how heterocyclic amines cause the DNA damage that can lead to breast cancer.
“There are several reports in the literature which suggest that some heterocyclic amines form DNA adducts in breast tissue of women and in exfoliated epithelial cells of lactating mothers. These adducts are an indication of potential DNA damage,” says Turesky.
He also notes there is some laboratory evidence indicating these compounds can have estrogenic activity and may contribute to tumor growth.
So what should women do?
“It is probably unwise to frequently eat meats that are cooked very well-done or charred. The meats should be cooked at sufficient temperature to inactivate pathogens, but not excessively charred. This will result in lower exposure to HCA,” recommends Turesky.
Cutting back on frying, broiling, or barbecuing may not necessarily reduce your risk of breast cancer, but it will result in fewer heterocyclic amines formed and consumed.
For now, I’ll take mine rare.
Fund free mammograms for women in need just by clicking—it’s free.
