Is Highly Cooked Meat Linked to Cancer?
Reprinted from the Community Connections Newsletter, Fall 2008
African American men have the highest rate of prostate cancer in the world. Part of the problem, according to researchers at Alta Bates Summit Medical Center, might be the result of eating too much meat cooked with high heat.
One potential culprit, they believe, is a group of chemicals called heterocyclic amines (HCAs) that develop in meat that is cooked at high temperatures over direct heat. Early research shows that consuming HCAs may elevate prostate-specific antigen (PSA), which is associated with prostate cancer.
To learn more, researchers from the Markstein Cancer Education and Prevention Services at Alta Bates Summit Medical Center (partnering with UCSF and Lawrence Livermore National Laboratory) conducted a study of eating habits of African American men between the ages of 40 and 70 who had no history of prostate cancer, and asked them about their diet over the previous year. The men shared information about their typical food portions, including how often they ate meat and how it was cooked.
One study, published in the Journal of Prostate Cancer and Prostatic Diseases, reveals that African American men consume twice the amount of HCAs as do their Caucasian counterparts. Chicken appears to have the highest levels of HCAs among all the meats that were assessed.
"We think there are many causes of prostate cancer, and potentially this is one of them," explains Leslie Paine, M.O.T., O.T.R., manager of Markstein Services. "So many of the African American men who participated in this study knew someone who had been touched by prostate cancer. Many were participating because they want to help change that."
Barbecuing, which blackens meat, also creates cancer-causing carcinogens. Research done by Alta Bates Summit, Lawrence Livermore National Laboratory, University of California, Livermore and University of California San Francisco, has shown that when chicken, beef, lamb, or fish is cooked so that it maintains a high, sustained internal temperature - whether it be barbecued, fried grilled or broiled – HCAs can form.
Another interesting finding – the researchers found that cruciferous vegetables, such as broccoli, can block the effects of HCAs, but only if they are eaten two days prior to eating HCA-laden meat. The study also showed that adding moisture to meat reduces the formation of HCAs, so it’s a good idea to marinate meat prior to cooking it.