One of the many arguments offered in the never-ending manufactroversy surrounding water fluoridation is that it causes cancer. This unsupported claim is nothing new and while it has been addressed many times it continues to periodically pop up and make the rounds again and again. In the age of the internet misinformation spreads quickly and myths die hard. The “natural health” blogosphere often capitalizes on this cycle of misinformation, dredging up outdated scare stories and spinning them as accepted fact. One such article from Natural Society reads,
In 1977, it was shown that fluoridation caused about 10,000 cancer deaths in epidemiological studies by Dr. Dean Burk, former head of the Cytochemistry Section at the National Cancer Institute and Yiamouyiannis.
This extraordinary claim originated with a paper on the subject of fluoride and cancer, titled “Fluoridation and cancer, age-dependence of cancer mortality related to artificial fluoridation”, which was originally put forward in 1975 and then again in 1977 by Dr. Dean Burk and fellow fluoridation opponent John Yiamouyiannis¹. However, the paper was not well received by the majority of scientists at the time and the paper’s methodology was criticized, such as for failure to adjust for important variables. Numerous subsequent scientific studies from the US, Ireland, Taiwan, Wales, Australia, and New Zealand, including a review of over 50 published studies contradicted Burk’s conclusion and found no evidence to support such an outrageous claim. The CDC has since been quoted saying,
at this time, the weight of the scientific evidence, as assessed by independent committees of experts, comprehensive systematic reviews, and review of the findings of individual studies does not support an association between water fluoridated at levels optimal for oral health and the risk for cancer, including osteosarcoma.
The American Cancer Society has also gone on record stating, “Scientific studies show no connection between cancer rates in humans and adding fluoride to drinking water.” But rather than listen to the scientific community, fluoridation opponents prefer to stay in their echo-chamber with select fringe “experts” where they can build their conspiratorial narratives.
Anti-fluoridation activists love to cite Dr. Burk, who has gone so far as to say that “fluoridation is a form of public mass murder.” As the past head of the National Cancer Institute’s Cytochemistry Sector² from 1938 to 1974, Burk is often cited as an unquestionable expert. However, Dr. Burk is an outlier on this issue in the scientific community. While Dr. Burk had a long scientific career and was notable as a co-discoverer of both biotin and a MRI prototype, a closer look at his career raises serious questions about his credibility. Burk’s approach to fluoridation was one of an activist more than a scientist. The self-correcting model of science advances on the basis of new evidence, yet Burk was never able to accept the mounting evidence against his favored hypothesis.
Burk’s quackery did not end at his anti-fluoridation activities however, he was also known for his support of the now disproven and potentially dangerous cancer “cure” laetrile. While in initial in vitro experiments Burk claimed to see “cancer cells dying off like flies“, these results are now understood to be very misleading and subsequent in vivo experimentation did not support the claims made for laetrile. A 2011 Cochrane Review of over 63 papers found “no reliable evidence for the alleged effects of laetrile or amygdalin for curative effects in cancer patients.” A common theme of Burk’s career was an over-confidence in preliminary data, while having a lack of respect for peer review and scientific criticism³.
Unfortunately even distinguished scientists are not above quackery. This can happen when a researcher strays outside their field of expertise, as is common among those cited by promoters of pseudoscience, though it can even occur with respected researchers within fields related to their expertise. Linus Pauling was a Nobel Laureate and admired chemist, yet in his later life he became a major proponent of high-dose vitamin C as a cancer cure, a worthless “treatment”. Peter Duesberg, a professor of Molecular and Cell Biology at the University of California, Berkeley, may be responsible for hundreds of thousands of deaths for his promotion of HIV/AIDs denial. Luc Montagnier, who was awarded the Nobel prize for co-discovery of the human immunodeficiency virus (HIV), has gone down the rabbit hole with his own crank theory of the true cause of autism. Unfortunately there is no shortage of once respectable-researchers-turned-cranks. This is why it is important to consider the scientific consensus formed by relevant experts, rather than the statements of outspoken advocates on the fringe, even though they may have a degree and the air of authority.
1. Yiamouyiannis was a dedicated anti-fluoridation advocate and author and his work is held in high regard among fluoridation opponents. Like Burk, Yiamouyiannis was not content to be a single issue crank, he also denied a link between HIV and AIDs as well as opposing vaccination. In 2000 he died of colorectal cancer, he had chosen to forgo science-based medicine and instead sought “treatment” in Mexico in the form of vitamins and laetrile.
2. NOT head of all NCI research as is sometimes touted.
3. Burk also developed of what he considered a “safer” cigarette filter that incorporated charcoal. Evidence of its effectiveness was lacking however.
Fluoride & Heart Disease?
Fluoride & Brain Damage
Fluoride & the Brain: Déjà Vu
Fluoride & the Brain: Strike 3, You’re Out!
Fluoride & the Brain: The China Studies
Science by Press Release: Fluoride & IQ
How do scientists become cranks and doctors quacks? by David Gorski