Study Determines Processed Meat Increases the Risk of Polyps

hot dogs processed meat
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A study published in the journal Carcinogenesis concluded that consuming processed meat such as bacon, pepperoni, and hot dogs can increase the risk of developing colorectal polyps. This is of concern because cancer of the colon and rectum develops from polyps. An increased risk of polyps means an increased risk of developing cancer.

When they compared polyp occurrence in people who consumed the most processed meat vs. people who consumed the least, the results were pretty convincing.

People who consumed the most processed meat were twice as likely to develop polyps as those who consumed the least.

This study compared 146 patients at the National Naval Medical Center in Bethesda, Maryland who had colorectal adenoma (polyps) with 228 people who did not have any polyps. They completed a food frequency questionnaire about their diet the 12 months before their colonoscopy. They answered questions in details about the type of meat they ate and how it was cooked.

What's So Bad About Processed Meat?

The researchers attributed the increased risk of polyps to the presence of nitrates (NaNO3) and nitrites (NaNO2). Both are preservatives that allow processed meat to maintain its redness. They're why SPAM is pink instead of gray. Processed meat that isn't pink, like canned tuna and chicken, doesn't contain nitrates and nitrites. They note that vegetables are the main source of nitrates in the diet, but they were interested in the additional nitrates from meat.​

How Can You Apply This Research to Your Life?

The take-home message from this study is to limit your consumption of processed meat if you're interested in lowering your risk of developing colorectal cancer. If you know someone who practically lives off of processed meat, you can add this research to your arsenal of reasons why that person should adhere to colon cancer screening guidelines.

The US Centers for Disease Control Agency for Toxic Substances and Disease Registry notes that epidemiological and toxicological studies on humans have not shown a definitive relationship between nitrate intake and the risk of cancer. The jury is still out on this question.

Related Articles:


  1. "Nitrate/Nitrite Toxicity: What Are the Health Effects from Exposure to Nitrates and Nitrites?" Agency for Toxic Substances and Disease Registry (ATSDR). Accessed 4 Dec. 2015 [].
  2. Ward, M. and Cross, A. "Processed Meat Intake, CYP2A6 Activity, and Risk of Colorectal Adenoma." Carcinogenesis Published online ahead of print 2 Feb. 2007. Accessed 6 Feb. 2007.