A small study seems to suggest that eating a lot of grilled, barbecued, and smoked meat may decrease survival after breast cancer. Still, there are questions about the study.
The research was published in the Jan. 5, 2017 issue of the Journal of the National Cancer Institute. Read “Grilled, Barbecued, and Smoked Meat Intake and Survival Following Breast Cancer.”
When meat is cooked at high temperatures until well-done, a group of chemicals called heterocyclic amines (HCAs) forms. The longer and hotter the cooking, the more HCAs form, especially in the blackened parts of the meat. The National Cancer Institute has identified 17 HCAs that may increase the risk of cancer. Another group of chemicals -- polycyclic aromatic hydrocarbons (PAHs) -- form in smoke produced when fat burns or drips on hot grill coals. PAHs have been linked to breast cancer.
In this study, the researchers interviewed 1,508 women who lived in Long Island, NY, who had been diagnosed with DCIS or early-stage breast cancer between Aug. 1, 1996 and July 31, 1997. About 73% of the women were 50 or older when they were diagnosed. The women were interviewed within 3 months of being diagnosed with breast cancer. The researchers asked the women about the types of food they ate, including:
- grilled/barbecued beef, lamb, and pork
- smoked beef, lamb, and pork, such as bacon or ham
- grilled/barbecued poultry and fish
- smoked poultry and fish, such as smoked turkey or lox
The women were asked about how much of these foods they ate in each decade of their lives. The researchers also asked the women to tell them when during the year -- spring, summer, winter, or fall -- they ate the most grilled, smoked, or barbecued meat.
Five years later, the researchers asked the women similar questions about their grilled, smoked, and barbecued meat-eating habits since they had been diagnosed. If a woman had died during the 5 years, the researchers asked a family member (called a proxy) to answer the questions. Overall, 1,033 women or their proxies completed the second interview. During the study, 597 women died; 39.7% of these deaths were related to breast cancer.
The researchers found:
- Compared to women who ate less grilled, barbecued, and smoked meat before being diagnosed with breast cancer, women who ate more were more likely to die from any cause.
- When the researchers looked at each of the four types of meats individually, there were some associations, but none of them were statistically significant, which means they could have been due to chance and not because of what the women ate.
While the researchers said that the results support the hypothesis that eating a lot of grilled, barbecued, and smoked meat may increase mortality after a breast cancer diagnosis, they also said that they could not rule out chance as an explanation for some of their findings.
It’s also important to know that this study asked the women to recall what they ate during each decade of their life. This means that women who were older than 50 had to remember in detail what they ate when they were 20 years old. Since many people can’t remember what they ate 6 months ago, it seems very, very unlikely that the women accurately remembered what they ate in their 20s, 30s, 40s, and 50s.
The conclusion of this paper is completely dependent on the women accurately remembering what they ate. So, since it’s unlikely the women’s memories are correct, the paper’s conclusion has to be questioned.
Also, all the women in this study lived in Long Island, so it’s unclear how widely these results can be applied to women who live in other areas.
Still, we do know that HCAs and PHAs produced when meat is charred are linked to cancer. To keep your exposure to these chemicals as low as it can be, you can:
- Choose lean cuts of meat and trim the fat to avoid PHAs.
- Grill at lower temperatures.
- Consider precooking (roasting or baking) meat before grilling to cook off fat.
- Don't use recipes for "blackened" foods.
- Trim off any charred or burned parts of food.
- Avoid overcooking (and undercooking) by using a meat thermometer to cook meat to the correct temperature indicated on the thermometer.
- Marinate meats in herb mixtures to reduce HCAs. Research shows the herbs in marinades reduce HCAs.
For more information on healthy eating and how it can help you during and after breast cancer treatment, visit the Breastcancer.org Nutrition section.