Megan Cole and Claire Karlsson
You have probably heard it many times already–whether from your doctor, a health magazine, or a health promotion poster: don’t eat too much red meat or processed foods. But it’s processed red meats, like bacon, hot dogs, and salami, that are the biggest problem.
Red meats vs. Processed red meats
In October 2015, the International Agency for Research on Cancer of the World Health Organization concluded that processed meats cause cancer. Based upon a review of over 800 studies, 22 scientists from ten countries determined that processed meats can cause colorectal cancer and probably stomach cancer.1 Although red meat consumption is associated in various studies with pancreatic and prostate cancer, it is not possible to conclude whether red meat causes cancer, or whether people who eat more red meat tend to have other poor health habits that are the real causes of these cancers.
Not only are bacon, hot dogs and other processed meats now blamed for causing cancer, but they have also been linked with heart disease and diabetes. A 2010 study led by Dr. Renata Micha from the Harvard School of Public Health analyzed 20 previous studies that looked at the relationship between eating red and processed meat and developing heart disease and diabetes 2 The results showed that eating red meat did not predict whether someone had these diseases. Instead, the researchers found that for each additional portion of processed meat consumed each day (50 grams, or about one hot dog or two slices of deli meat), a person was 42% more likely to develop coronary heart disease and 19% more likely to develop diabetes.
Why the difference?
When comparing red meats with processed meats, there are some key nutritional differences. While levels of saturated fats and cholesterol are usually similar in processed and unprocessed meats, processed meats generally have four times the amount of sodium and 50% more preservatives than red meats.3 Researchers suggest that these increased levels of sodium and preservatives may explain the increase in health risk. To determine if that is true, further research is needed. What is known, however, is that sodium increases blood pressure and preservatives have been shown to reduce tolerance to sugars. High blood pressure contributes to heart disease and reduced tolerance to sugars increases the risk of diabetes.
…but don’t pick up that steak so fast.
Does this mean that you are now free to eat all the red meat you want as long as it isn’t processed? Well, no. In previous studies, red meat has been linked with heart disease by raising unhealthy cholesterol levels due to its high saturated fat content. Chicken and fish are much lower in unhealthy fat. Although less conclusive than the studies of processed meats, there is evidence that eating other red meat increases the risk of developing various cancers. Plus, reducing red meat consumption may help combat the effects of climate change, because meat production emits harmful greenhouse gases.4
What meats should I eat and what meats should I avoid?
As outlined by the US Department of Agriculture (USDA), the following should be taken into consideration when selecting meats for you or your family:
• Choose lean or low-fat meat and poultry. Avoid ground beef that is less than 80% lean (the leaner, the better), and choose skinless chicken.
• If you do buy processed meats, be sure to read the ingredients and Nutrition Facts label to help limit sodium intake. Look for products labeled “low sodium,” “reduced sodium,” or “no salt added.” To be considered “healthy,” products must not exceed 600 mg of sodium per serving.
• Consider eating fish rich in omega-3 fatty acids, such as salmon, trout, and herring, or getting protein from other non-meat sources, such as beans, legumes, almonds, sunflower seeds, and egg whites.5
Is ALL processed meat worse than red meat?
All processed meats are not necessarily worse than all other red meats, as the “healthiness” of a meat depends upon the number of calories per serving as well as its sodium and fat content. For instance, lean deli meat may be healthier than a fatty unprocessed hamburger or steak. However, in general, most processed meats will be nutritionally inferior to unprocessed red meats. Products such as bacon, sausage, and hot dogs, with the possible exception of lean and low-sodium varieties, are fattier, saltier, higher in calories, and contain more additives than unprocessed red meats such as beef, pork, and lamb.
The bottom line
Products higher in calories, saturated fat, and sodium tend to increase weight, fat, and blood pressure, which in turn, may lead to the development of heart disease and/or diabetes. So? Eat a balanced diet with plenty of whole grains, fruits, vegetables, low-fat dairy, and lean proteins. Enjoy red meat in moderation and remember: if you have to choose between a hot dog or a hamburger, the unprocessed meat of the hamburger is the safer bet when it comes to avoiding cancer, coronary heart disease and diabetes. (But also remember that the salt, ketchup, and pickles you add to that burger can make it even saltier than a hot dog).
- Bouvard, Véronique; Loomis, Dana; Guyton, Kathryn Z; Grosse, Yann; El Ghissassi, Fatiha; Benbrahim-Tallaa, Lamia; Guha, Neela; Mattock, Heidi; Straif, Kurt. (October 2015). “Carcinogenicity of consumption of red and processed meat”. The Lancet. DOI: http://dx.doi.org/10.1016/S1470-2045(15)00444-1. ▲
- Micha R, Wallace SK, Mozaffarian D. (2010 May 7) “Red and Processed Meat Consumption and Risk of Incident Cornary Heart Disease, Stroke, and Diabetes Mellitus: A Systematic Review and Meta-Analysis”. Journal of the American Heart Association (Circulation) 121(1):2271-2283. ▲
- Sinha R, Cross AJ, Graubard BI, Leitzmann MF, & Schatzkin A (2009 March 23) Meat intake and mortality: a prospective study over half a million people. Archives of Internal Medicine 169(6):562-571 ▲
- Powell R (2008) Eat less meat to help the environment, UN climate expert says. Telegraph. ▲
- United States Department of Agriculture (USDA) (2010). Inside the Pyramid (Meat). ▲