Nitrates, Nitrites and NO, NO, NO!
For years the conventional wisdom has blamed any ill health effects from bacon at the feet of the nitrites and nitrates, such as the aforementioned sodium nitrite, that are added during the preservation process.
But what are these compounds and what is the truth behind this porcine puzzle and the “no artificial nitrates/nitrites added” bacon bluster?
Both nitrites and nitrates in this setting refer to compounds which contain a nitrogen molecule and two oxygen molecules in the case of nitrites, and three oxygen molecules in the case of nitrates. They occur naturally in many forms throughout the environment, including many of the fresh, wholesome foods we eat (more on that later) and are produced in our own bodies where they are critical for the maintenance of life.
Like many of the food myths that have become conventional wisdom, the story about the detrimental effects of nitrates and nitrites began with animal experiments during the 1970s.
The original research that started the row was performed under the direction of Dr. Newberne at MIT at the request of the FDA. This in turn was generated from public concern over possible carcinogenic effects of nitrates and nitrates. Previously for hundreds, if not thousands of years, nitrates and nitrites had been valued as a healthful adjunct; dating back to at least 2200 BC where the addition to meat preservation was in the form of naturally occurring saltpeter (potassium nitrate).
The modern concern over the carcinogenicity of nitrites centered on the development of lymphatic cancer in a strain of rats as demonstrated in Dr. Newberne’s study done in the mid-1970s. However, a more careful analysis in 1978 by an outside review found that than the original MIT study was flawed. In 1980, a final report from the intra-agency Ad Hoc Working Group (IAWG) consisting of scientists from the FDA, USDA, and NIH was issued on August 15 which failed to confirm the carcinogenicity of nitrite.
When the original pathology slides were reevaluated by a committee consisting of members from fifteen different universities; they found a “reduction of incidence [of lymphomas] to approximately 1% among treated and control groups. This rate of lymphoma incidence is similar to that usually seen spontaneously in Sprague-Dawley rats.”[i] One of the reasons for the discrepancy may have been, as later determined by an investigation under the auspices of the Government Accounting Office (GAO), that “a major portion of his pathological diagnoses was done by students not Dr. Newberne himself.”[ii] The final report stated unequivocally that nitrite is not a carcinogen at the doses studied.
These findings were reconfirmed in a 1981 review of nitrites, nitrates and human cancer risk performed by National Academy of Sciences. Today more than fifty additional studies and reviews have failed to demonstrate a link between nitrites, nitrates and the risk of developing cancer.
Part 3 to follow
[i] (St. Hilaire, 2014) page 48
[ii] (St. Hilaire, 2014) page 51