Bacon, Cancer, and How We Cook
Headlines hit the news in the fall of 2015 that “Bacon Causes Cancer!” These sensational headlines were, in fact, grounded in science. A group of 22 scientists from the World Health Organization met in October of 2015 to evaluate whether red meats or processed meats were cancer causing foods. The group evaluated more than 800 studies conducted around the globe on the relationship between more than 15 types of cancer and the consumption of red or processed meats. Based primarily on data related to colorectal cancer, the scientists concluded that processed meats are “carcinogenic to humans” and that red meats are “probably carcinogenic to humans.”[i]
Why would processed or red meats cause cancer?
Meat processing can create cancer-causing compounds: N-nitroso-compounds (NOCs) and polycyclic aromatic hydrocarbons (PAHs). High-temperature cooking can also create cancer-causing compounds: heterocyclic aromatic amines (HAAs) and advanced glycation end products (AGEs). This alphabet soup of chemicals can damage human DNA and possibly initiate or further the progression of cancer.
Cancer-causing compounds form when meat proteins and fats are exposed to high heat. Curing and smoking create the highest levels of cancer-causing compounds in processed meats, while grilling and barbecuing create the highest levels in cooked meats. A list of the AGE content of 549 different foods has been published in the Journal of the American Dietetic Association.[ii] At the top of this list is a broiled hot dog, with a whopping 10,143 AGE units per serving. Pan-fried steak comes in at 9,000 AGE units per serving, and barbecued chicken at almost 8,000. To put this in perspective, steamed salmon has only 900 AGE units per serving, and a poached egg only 27.
Taken together, this information does not mean that you need to stop eating meat. It does mean that you need to pay attention to the way that you prepare it. Unlike many plant foods, which can be eaten raw or sprouted, most meats need to be cooked for safety reasons. Cooking methods that create the highest levels of carcinogens are those that use high and dry heat: pan-frying, deep-frying, broiling, grilling, barbecuing, and smoking.
Cooking methods that create the lowest levels of carcinogens are those that use low and moist heat: boiling, poaching, steaming, and stewing. There is also a fascinating method of cooking that is used in some gourmet restaurants, called “sous-vide.” This method seals the food into plastic bags and cooks it in warm water, at a much lower temperature than typical cooking, for as long as 96 hours.
So what about bacon?
The scientists of the World Health Organization concluded that processed meats are carcinogenic to humans. There are a couple of reasons not to get overly concerned about this conclusion. First, the conclusion is based entirely on epidemiological studies, which means that there is virtually no way to be certain of cause and effect. People who eat bacon may have other unhealthy habits, or the bacon that people eat may be laden with toxins from industrial farming techniques. Second, their studies showed that eating 2 slices of bacon every day increases your risk of colorectal cancer by 18%. Compared with the increased risk of lung cancer from smoking (2,500%), occasional bacon may not be enough to tip the scales out of your favor.[iii]
Red meats are a rich source of biologically available protein and important nutrients, such as B vitamins, iron, and zinc. Organic meats are raised without exposure to artificial hormones, antibiotics, pesticides, or other potentially cancer-causing toxins. A handful of conscientious companies process uncured bacon, sausage, and lunch meats without added nitrates. This is the ideal method for bacon processing.
A healthy diet should include quality protein sources. Protein can come from a wide variety of foods: beans, nuts, eggs, fish, poultry, and even red or naturally processed meats. In addition, fresh fruits, vegetables, nuts, and seeds offer antioxidant protection against any potentially cancer-causing compounds in the diet.
Ideally, you should eat a whole food plant based diet. Dr. G eats a mostly plant based diet with naturally processed meats.
It can be tough to know if you’re eating right. If you want help planning healthy meals and snacks to optimize your health, talk with one of our talented nutrition therapists. We look forward to serving you!
[i] Bouvard V, Loomis D, Guyton KZ, et al. Carcinogenicity of consumption of red and processed meat. Lancet Oncol. 2015;161599-1600.
[ii] Uribarri J, Woodruff S, Goodman S, et al. Advanced glycation end products in foods and a practical guide to their reduction in the diet. J Am Diet Assoc. 2010;110(6):911-16.e12.
[iii] Zhang, S. Bacon Causes Cancer? Sort Of. Not Really. Ish. Wired Web site. http://www.wired.com/2015/10/who-does-bacon-cause-cancer-sort-of-but-not-really/. Accessed January 6, 2015.
About the Author: Dr. Gerard Guillory, MD is Board Certified in Internal Medicine and has published two books on Irritable Bowel Syndrome (IBS). In 1985, he opened The Care Group, PC. Today, his clinic is a Primary Care facility that is a hybrid of functional and traditional medicine treating patients with digestive disorders, autoimmune disease, and other conditions. You can learn more about Dr. Guillory here.