People who eat processed meats like bacon, sausage, and deli meats have a 42% higher risk of getting heart disease and a 19% higher risk of getting Type 2 diabetes.
A new study by researchers at the Harvard School of Public Health (HSPH) in Boston found that people who eat processed meats like bacon, sausage, and deli meats have a 42 percent higher risk of getting heart disease and a 19 percent higher risk of getting Type 2 diabetes for each daily serving of about 1.8 ounces (50 grams) they have. In other words, the 42 percent higher risk for heart disease and increased diabetes risk comes from eating as little as 1.8 ounces of processed meat.
The researchers systematically winnowed 1600 studies from all over the world down to the 20 that were most relevant. (This is called a “meta-analysis” because it is an analysis of other studies.) These 20 studies involved 1,218,310 people from 10 countries in North America, Australia, Europe and Asia. The researchers defined any meat prepared by curing, salting, smoking or adding chemical preservatives as processed. Unprocessed meats were defined as those served in the state they were taken from pigs, cattle, or sheep (but cooked). Poultry and vegetable sources of protein were excluded from the study.
Interestingly, in this study, eating unprocessed red meat — beef, pork, and lamb — did not correspond to a higher risk for either disease in this study. I’ve reported very different results from prior studies. In fact, last year, I wrote a health blog about a study conducted by the National Institutes for Health and the AARP tracking more than half a million people between the ages of 50 and 71 for more than a decade. That study found that those subjects who ate the equivalent of a small hamburger daily had a 30 percent elevated risk of death from all causes, but particularly from cancer and heart problems. The elevated risk for women was particularly startling, with those who ate the most red meat, increasing their mortality risk by 36% and their risk of dying from heart failure by 50%. (Note: we’re not talking about grass fed or organic beef here, which might significantly change the equation.)
In any event, it makes sense that processed meats would be more deadly than the unprocessed variety, but not because of the amount of saturated fats and cholesterol. These were similar in the processed and unprocessed meats. So were the “lifestyle factors” of those eating processed and unprocessed meats. The real difference, it seems, was the much higher sodium nitrate preservatives content found in processed meats. According to study leader Dariush Mozaffarian, assistant professor in the HSPH department of epidemiology, “…processed meats contained, on average, four times more sodium and 50% more nitrate preservatives. This suggests that differences in salt and preservatives, rather than fats, might explain the higher risk of heart disease and diabetes seen with processed meats, but not with unprocessed red meats.”
While this is not exactly new news, it is the first worldwide study to indicate a possible negative impact of salt and nitrate preservatives on the body. I’ve mentioned in many places that refined commercial, iodized table salt is a contributor to high blood pressure, a cause of heart disease. (Note: not all salts are created equal.) Nitrates are another story. Found naturally in vegetables and fruits, nitrates are added to meats and other foods to maintain color and act as a preservative. The body converts nitrates to nitrites, and nitrites have a controversial relationship to cancer, with some studies showing a high correlation to cancer, and others showing none. The National Academy of Science, for one, maintains that nitrites are unlikely to cause any kind of cancer, but the Harvard study cited above shows a clear correlation between intake of sodium and nitrates in processed meats and an increased risk of heart diseases and diabetes. Moreover, it also indicates that, despite the research controversies, there may be more of a link between intake of nitrates and colorectal cancer, as well as other cancers than recognized by the medical establishment.
Interestingly, physicians use nitrates to intervene in cases of heart attacks and angina because it dilates the arteries of the heart and increases blood flow. There are three main forms — nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. When used in these forms, it can be injected into the bloodstream (in heart attack emergencies), taken as a spray, a pill, a paste, or a patch. The hotdog variety of nitrate, however, serves no purpose other than sensory pleasure for those so inclined. I know of no doctor who recommends eating a hotdog when experiencing a heart attack or angina.
Again, there’s plenty of evidence that processed meats are deadly. The HSPH study showed that a mere serving a day is enough to have dire impact. The upshot is that if you’re going to eat the cow, it’s probably somewhat better to eat it in a more cow-like state. On the other hand, if you want to live longer and stay healthier, you’re probably better off not eating the cow at all…or at least restrict your eating to organic, grass fed cows.