In the late 1970s and early 1980s, nitrosamines -- and consequently bacon and other smoked pork products -- were in the news. The claim and concern was that they contributed to cancer risks. After much investigation, debate and research, it was determined that only obscenely massive consumption of products with nitrosamine traces might present a concern.

The issue was generally tabled and concerns calmed. Certainly in recent years bacon has become a flavor favorite, especially accompanying a burger.  

Now, a Harvard University study suggests a connection between bacon and boneless chicken breast have a higher risk of bladder cancer than people who don't eat those products. Specifically, people who eat bacon at least five times a week are 59 percent more likely to develop bladder cancer than none eaters. (Researchers did not report the amount of bacon per meal.) The study also shows that people who frequently eat skinless chicken are 52 percent more likely to develop the same disease. Between the two consumption patterns, it's less likely that a person would eat bacon five times in a week, versus making skinless check a regular menu item. 

Nitrosamines and heterocyclic amines (which forms when meat is cooked at high temperatures) are the speculative agents, according to the study, which appears in the American Journal of Clinical Nutrition. Chicken with skin contains smaller amounts of heterocyclic amines.

Researchers studied 136,000 people who were tracked for as much as 22 years, during which 808 developed bladder cancer. The researchers did, however, find that people who ate bacon and other processed meats also were more likely to smoke, consume more fat and fewer vitamins, and be less likely to exercise.

Researchers admit that more research is needed to determine causality between high bacon and chicken consumption and bladder cancer. That said, it does put nitrosamines back in the news.

Source: Meatingplace.com, Harvard University