The Meat You Eat and Cancer
By Gary Null PhD, Amy Mitura Esq. and Neal Greenfield, Esq.
Who are we supposed to believe when it comes to our health? There is a movement towards plant-based foods with many leading physicians seeing the reversal of conditions in patients following plant-based diets. Unfortunately, people researching the subject may come across writings by Dr. Stephen Barrett. Regarding nutrition, Barrett relies on the now scientifically debunked advice of the food pyramid where meat and dairy are the top bases of the diet, followed by wheat products, such as breads and pastas. Fruits and vegetables are given less significance. As Barrett has been a primary source for health-related articles on Wikipedia, influencing a massive audience, we decided to look at a few of the statements he has made over the years. Does he deserve to be considered an unbiased, objective authority on the subject? Judge for yourself…
In his book The Health Robbers (last edition in 1993), Barrett argues that quacks and charlatans “claim that most Americans are poorly nourished,” saying, “this is an appeal to fear that is not only untrue, but ignores the fact that the main forms of bad nourishment in the United States are undernourishment among the poverty-stricken and overweight in the population at large.” (32) Many of Barrett’s assertions are based on the U.S. government’s original Food Guide Pyramid, which, according to Harvard School of Public Health, “conveyed the wrong dietary advice. And MyPyramid, its 2005 replacement was vague and confusing.” Again Barrett was wrong. Terribly wrong.
Barrett has also been consistently incorrect about one of the food groups in that pyramid—meat and the chemical used during the curing process, sodium nitrite. According to Barrett, “Nitrosamines have been found to cause cancer when fed in large amounts to test animals. However, sodium nitrite is a normal component of human saliva, and some 80 percent of the nitrite in the body comes from eating celery, beets, radishes, lettuce, spinach, and other commonly consumed vegetables. So it seems a bit absurd to panic about adding small amounts of substances that prevent serious health threats while remaining unconcerned about larger amounts that are present naturally.” (Barrett 70-71)
Barrett’s comparison of nitrosamines to sodium nitrite and commonly consumed vegetables is misleading at best. According to the National Cancer Institute, “vegetables also contain compounds that prevent the formation of N-nitroso compounds (NOC), which are known to cause cancer in animals and may cause cancer in humans.” Studies have shown increased risks of colon, kidney, and stomach cancer among people with higher ingestion of water nitrate and higher meat intake compared with low intakes of both. Other studies have shown modest evidence that higher nitrate intake can increase the risk of thyroid cancer and ovarian cancer among women.
There are several notable studies that appear in the peer-reviewed medical literature showing the increased risk of cancer associated with higher nitrate intake:
In 2013 the International Journal of Cancer published the Shanghai Women’s Health Study. The study, conducted by the University of Chicago, evaluated the effects of nitrite and nitrate from meat consumption in over 73,000 Chinese women. The researchers concluded that “women consuming higher levels of nitrite from animal sources, particularly from processed meat, may have an increased risk of thyroid cancer.”
According to the Harvard School of Public Health, the World Health Organization (WHO)’s International Agency for Research on Cancer (IARC) found that “consumption of processed meat is ‘carcinogenic to humans,’ and…consumption of red meat is ‘probably carcinogenic to humans.” The IARC Working Group, comprised of 22 scientists from ten countries, evaluated over 800 studies. “Conclusions were primarily based on the evidence for colorectal cancer. Positive associations between processed meat consumption and stomach cancer, and between red meat consumption and pancreatic and prostate cancer were also identified. “Meat processing such as curing (by adding nitrates or nitrites) or smoking can lead to the formation of potentially cancer-causing (carcinogenic chemicals such as N-nitroso-compounds and polycyclic aromatic hydrocarbons (PAH).”
Other health risks associated with meat consumption include cardiovascular disease and stroke, diabetes, obesity, acne, erectile dysfunction, and Alzheimer’s. A University of Wurzburg analysis of 11,000 middle-aged people concluded that those who consumed the most red meat had a 47 percent higher risk of ischemic stroke caused by artery blockage. A more recent 2016 Mayo Clinic analysis, published under the heading “Is Meat Killing Us?” reviewed 1.5 million Americans and found that all health causes for mortality was higher among regular meat-eaters.
In an article published this June, the Union of Concerned Scientists informs us that “guidelines reflecting up-to-date science could have saved as many as 3,900 deaths from colorectal cancer and cut related medical costs by $1.5 billion.” Despite the fact that a review of the scientific evidence concluded that a healthy diet generally means less red and processed meat, the U.S. Department of Agriculture (USDA) and the Department of Health and Human Services (HHS), the federal agencies that have the final say on the guidelines, chose not to recommend eating less of either.
So perhaps it wasn’t “absurd to panic” about nitrates after all. And perhaps it wasn’t wise to assume that following the U.S. dietary guidelines would keep people well-nourished. In what seems like an attempt at humor, Barrett writes, “Every group of people on earth gets cancer. So do virtually all animals (vegetarians and meat-eaters alike)…” (Barrett 9) But perhaps they don’t get cancer “alike.” Clearly the science indicates that people who rely upon the Food Pyramid and Barrett’s suggestions get cancer more than other groups. Once again, it appears to be Stephen Barrett, and anyone using him as a source, who is the real Health Robber.
In conclusion, it is this simple, look on PubMed or any other legitimate resource and you will find a considerable amount of peer-reviewed studies–710 studies on plant-based diets and health, 4800 on vegetarian diets and health, 1059 on vegan diets and health, and 3454 on Meditteranean diets and health. Try to find one on meat-based diets and health…
Duke Med Health News. 2010 Jan;16(1):1-2.