LOS ANGELES — Finally, some good news for carnivores. Although several studies have linked a Western diet—including a high intake of red meat—to an increased risk of prostate cancer, a large prospective cohort study has narrowed the risk to well-done or very well-done meat.
The study, by Stella Koutros of the National Cancer Institute and colleagues, was presented as a poster at the annual meeting of the American Association for Cancer Research.
They found no association between prostate cancer and total consumption of meat, red-meat, chicken, bacon, sausage, processed meat, steak, hamburger, pork chops, or ham steaks. There also was no association between prostate cancer and the method used to cook the meat, including barbecuing, pan frying, or broiling.
Subjects in this analysis were enrolled in the Agricultural Health Study, a prospective cohort of 55,966 male pesticide applicators and their spouses in Iowa and North Carolina. After excluding more than 31,000 subjects for whom the investigators had no information on meat-cooking practices and another 1,424 subjects with prevalent cases of cancer, the investigators had 23,080 individuals and 197,017 person-years of follow-up available for analysis.
Among those individuals were 668 cases of prostate cancer, 613 of which were incident cases diagnosed after 1 year of follow-up. Advanced cases, defined as those in disease stage III or IV, numbered 140.
The subjects completed questionnaires on their dietary habits and cooking methods, and the investigators linked that data to a database of carcinogenic heterocyclic amines (HCAs) to estimate intake of three HCAs. The analyses were adjusted for age, state of residence, race, family history of prostate cancer, and smoking status.
The only statistically significant results involved the total intake of well-done or very well-done meat. Men in the highest tertile of total intake had a 22% higher risk of prostate cancer than those in the lowest tertile. Men in the highest tertile had almost twice the risk of having advanced prostate cancer as those in the lowest tertile.
Although high-temperature cooking methods result in the formation of carcinogenic HCAs, the increased risk associated with estimated intake of the three HCAs did not quite reach statistical significance. The researchers suggested that these HCAs may be correlated with the presence of other similar compounds that were not measured and that may be more closely related to prostate cancer risk.