 Why was there so much more lymphoma and leukemia risk among those eating just a small serving of chicken a day? The reasons are unclear. Certainly, there are industrial carcinogens like dioxins that may increase risk of non-Hochins lymphoma and have been found in meat and dairy. But the study did not observe an increased risk in association with high milk consumption, so that's probably not it. Secondly, poultry may contain oncogenic or cancer-causing viruses, especially if the meat is not cooked well. And it's interesting, there are actually studies in the US reporting a lower risk of lymphoma in women consuming well-done meat. You'd think it'd be the other way around, because of the heterocyclic. It means that cooked meat carcinogens created when you grill chicken, but not if it's the viruses in chicken that are responsible. Then how do you cook it? The more viruses you wipe out. Organic animal viruses, cancer-causing animal viruses, have been suspected as causes of lymphoma among farmers and slaughterhouse workers, but this is just preliminary. Meat consumption has not been connected with transmission of oncogenic viruses yet. And the third theory why poultry was so significantly associated with blood and lymph node cancers is maybe it's because chickens and turkeys are often treated with anti-parasitic drugs and antibiotics to enhance growth of the animals and to treat and prevent disease, especially given the conditions in which many of them are now raised. And indeed, antibiotic use has sometimes been associated with risk of lymphoma. However, it's unclear whether the association between antibiotic use and cancer risk is causing effect, and more importantly, whether antibiotic use in food animals can affect cancer risk in human beings. Bottom line, we just don't know yet why the cancer-chicken connection.