John Yiamouyiannis, Ph.D. (1943–2000) liked to call himself “the world’s leading authority on the biological effects of fluoride.”  He was for more than 25 years the most active antifluoridationists in the United States. He was very bright—and determined. Had he chosen a positive direction, he might well have made a valuable contribution to science. But he did not. Despite training as a biochemist, he became obsessed with the idea that water fluoridation is dangerous.
Yiamouyiannis received a B.S. degree in chemistry from the University of Chicago and in 1967 a Ph.D. in biochemistry from the University of Rhode Island. After working for about a year as a laboratory biochemist at Case Western Reserve University he was hired as as assistant editor (one of about 200 assistant editors) by Chemical Abstracts Service (CAS), a division of the American Chemical Society. His job was to abstract articles on chemical topics. In 1969 and 1970, he gave talks to various groups concerning his opposition to fluoridation. In 1970, CAS warned Yiamouyiannis that if he made more speeches where his opposition to fluoridation was identified with CAS, he would be fired. In 1972, he was placed on probationary status with CAS, which said that his work was inadequate. He immediately resigned and sued the company, but his case was dismissed .
Yiamouyiannis described his Chemical Abstract experience in testimony that he gave in a fluoridation lawsuit in South Carolina. Among other things, he said that in 1971 he attended a meeting at a high school “incognito” (wearing a bag over his head) and “made a dramatic representation that my employer didn’t want me to speak out on the subject.” In the South Carolina case, a citizens group asked the court to enjoin fluoridation as a “public nuisance.” The final order dismissing the case described Yiamouyiannis as “sincere” but lacking in scientific credibility .
After leaving Chemical Abstracts, Yiamouyiannis began manufacturing salad dressing in his garage but earned only about $1,500 per year doing this . In 1974, the National Health Federation (NHF) recruited him as “science director.” The letter that announced his hiring stated that fluoridation was NHF’s No 2 priority and that he had been hired to head its effort to “break the back of promoters’ efforts to fluoridate more American cities.”  He remained with NHF until 1980.
About two years before NHF hired Yiamouyiannis, it gave a $16,000 to the Center for Science in the Public Interest to do a study that NHF believed would supply “unassailable, up-to-date scientific data to help defeat fluoridation.”  The plan backfired, however, because the author, who was a competent researcher, concluded that although more research should be done, “the known benefits of fluoridation to dental heath far outweigh any risks which may be involved.” 
I saw Yiamouyiannis in action several times. He was personable and appeared sincere. Though public health officials regarded him as a terrorist, to the uninformed he seemed credible. His activities have frightened many communities into opposing fluoridation. If he didn’t appear in person, his presence—through his publications—was often felt where fluoridation was considered. In 1978, Yiamouyiannis reportedly charged $250 per day for his testimony in an antifluoridation court case .
In the late 1970s, he and I were invited by a government panel to discuss fluoridation oif a large City in Texas. When I mentioned that NHF’s own study had been favorable to fluoridation, he said he knew about the report but it had never been completed. Since I had a copy of the report , I pointed out to the panel that he was flat-out lying.
Fighting fluoridation is actually quite simple. Just claim that it causes cancer, damages the immune system, or causes dozens of other diseases. Or suggest that it is a form of pollution, will raise taxes, is undemocratic, or hasn’t been studied enough. Or use dozens of other ploys and hope that at least one will work. It isn’t necessary to convince people that all antifluoridation arguments are valid. A single doubt may be persuasive.
Yiamouyiannis used many such ploys, but his most persistent was that fluoridation causes cancer. Experts concluded that his reports were based on a misinterpretation of government statistics. In true “anti” fashion, he compared cancer death rates in fluoridated and nonfluoridated cities but failed to adjust for various factors in each city (such as industrial pollution) that are known to raise the cancer death rate . By 1977, independent investigations by eight of the leading medical and scientific organizations in the English-speaking world had refuted the cancer claims. That same year, at a Congressional hearing.Robert N. Hoover, M.D., a prominent epidemiologist who worked at the National Cancer Institute, discussed Yiamouyiannis’s errors in detail and said that his fluoride-cancer study “happens to represent the worst piece of work that has been done to date on fluoride.” 
In 1978, Consumer Reports published a two-part series on fluoridation that criticized Yiamouyiannis’s work and concluded:
The simple truth is that there’s no “scientific controversy” over the safety of fluoridation. The practice is safe, economical, and beneficial. The survival of this fake controversy represents, in Consumers Union’s opinion, one of the major triumphs of quackery over science in our generation .
A few months later, Yiamouyiannis filed suit for libel, charging that he had been defamed by Consumers Union’s report. After a lower court dismissed the suit , Yiamouyiannis appealed to the United States Court of Appeals for the Second Circuit, which upheld the dismissal. The appeals court’s ruling, issued in 1980, stated:
It is clear that [Consumers Union] . . . made a thorough investigation of the facts. Scientific writings and authorities in the field were consulted; authoritative scientific bodies speaking for substantial segments of the medical and scientific community were investigated. The unquestioned methodology of the preparation of the article exemplifies the very highest order of responsible journalism: the entire article was checked and rechecked across a spectrum of knowledge and, where necessary, changes were made in the interests of accuracy .
At about this time, Yiamouyiannis had a falling out with other NHF officials, left NHF, and founded the National Health Action Committee, which he described in its brochure as “a union of virtually every effective antifluoridation group in the country.” He also founded and operated the Safe Water Foundation, which in 1984 was renamed Center for Health Action. Without NHF support, however, Yiamouyiannis himself became much less effective.
Yiamouyiannis also sued Marvin A. Schneiderman, associate director of the National Cancer Institute. In 1978, Schneiderman had testified as an expert at a fluoridation hearing in Pennsylvania and later criticized one of Yiamouyiannis’s reports during an interview. The suit was brought against him individually, but the court dismissed the suit because he was acting on behalf of the agency and therefore immune from individual liability .
In 1985, a prestigious group appointed by the British Department of Health and Social Security issued yet another review of the cancer charge plus more recent studies from a dozen countries. Agreeing that fluoridation does not cause cancer, the group said, “The only contrary conclusions are in our view attributable to errors in data, errors in analytical technique, and errors in scientific logic.” 
During the same year, Yiamouyiannis’s credibility was attacked further when a team of public health experts from the Ohio Department of Health published a book analyzing his pamphlet, “A Lifesaver’s Guide to Fluoridation.” This pamphlet, which was invariably distributed wherever community fluoridation was considered, cited 250 references that supposedly backed up Yiamouyiannis’s claims that fluoridation is ineffective and dangerous . However, when the Ohio team traced the references, they found that almost half had no relevance to community water fluoridation and many others actually supported fluoridation but were selectively quoted and misrepresented. Eighty-six citations, for example, referred to studies conducted on plants or animals . In 1988, after Yiamouyiannis revised his pamphlet, the expert team produced a second edition of the book, which is now available online.
Yiamouyiannis also operated the Health Action Press, which produced three titles: Fluoride: the Aging Factor (1983, 1986, 1993), High Performance Health (1987), and AIDS: The Good News Is That HIV Doesn’t Cause It (1995), which he co-authored with Peter Duesberg, the leading HIV denialist. The jacket of his 1983 book stated:
Dr. Yiamouyiannis lives with his wife and six children on a 35-acre farm just outside of Columbus, Ohio. Their lifestyle revolves around a total preventive health care program with emphasis on a virtually fluoride-free diet. The results: all of his children are excellent athletes in excellent health. For the last twenty years, their total medical bill has been less than $500.
Yiamouyiannis was also opposed to vaccination. In High Performance Health, he expressed concerns that when vaccinations are given during the first few months of life, “it is likely that at least a portion of those vaccinated suffer permanent damage to the immune system.” He also speculated that vaccinated people would have a higher incidence of AIDS. There is no scientific evidence supporting either of these views.
In 1995, the British Dental Association published a critical summary of his activities .
In August 2000, the water district that serves Yiamouyiannis’s home community (Delaware, Ohio) approved fluoridation. A few months later, the Columbus Dispatch reported that he had died “after a long and noble fight with cancer.”  However, a subsequent report by Peter Barry Chowka indicates that Yiamouyiannis’s death was probably hastened by neglect. In September 1999, Yiamouyiannis described to Chowka that about a year earlier, he had begun having bloody stools and went to several Mexican cancer clinics where he was diagnosed with rectal cancer, treated with “IV drips of laetrile, vitamin C, and a whole bunch of other stuff,” and advised to have surgery and chemotherapy. However, he decided to reject conventional therapy and treat himself with what he considered to be nontoxic approaches . The prognosis for colorectal cancer depends upon its location at the time it is discovered . If Yiamouyiannis’s cancer had not spread beyond his colon at the time it was discovered, the 5-year survival rates with treatment were about 95% for “Duke Stage 1” and 75% for “Duke Stage 2.” It would be interesting to know whether his antipathy for standard medical care was indirectly responsible for his death.
- Yiamouyiannis J. Fluoride: The Aging Factor. Delaware, OH: Health Action Press, 1983, 1986.
- Opinion. Yiamouyiannis v. Chemical Abstracts et al. United States Court of Appeals, Sixth Circuit. Case 521 F.2d 1392.
Decided Sept. 15, 1975.
- Yiamouyiannis J. Testimony in Charleston Committee for Safe Water et al. v. Commissioners of Public Works et al. 286 S.C. 10, 331 S.E.2d 371 (S.C. Ct. App. 1985). Decided May 30, 1985.
- Yiamouyiannis J. Testimony before the Pennsylvania Environmental Hearing Board, Docket No. 73-704-N. Sept 24, 1974.
- Crecelius CI. Fundraising letter to NHF members. Nov 1, 1974.
- Long H. SPECIAL URGENT APPEAL (fundraising memo to NHF members), January 1872.
- Statement by director, fluoride project, Center for Science in the Public Interest. Reported in USPHS PPB-54, March 1973.
- Schmitz J. Why fluoride foes sank $50,000 in fluoride suit. The Pittsburgh Press, Nov 22, 1978.
- Prival MJ. Fluorides and Human Health. Center for Science in the Public Interest, December 1972.
- National Cancer Institute. Statement by the National Cancer Institute on fluoridation studies by the National Health Federation, April 25, 1975.
- Hoover RN. Testimony. In Fluoridation of Drinking Water. House Committee on Government Operations, October 12, 1977, p 253.
- Fluoridation. Consumer Reports 43:392-396, 480-482, 1978.
- Memorandum and order. John Yiamouyiannis v. Consumers Union of United States. U.S. District Court, Southern District of New York, Case No, 78 Civ. 4721, May 30,
- Opinion. John Yiamouyiannis v. Consumers Union. U.S. Court of Appeals for the Second Circuit. Case No. 470, Sept Term 1979. Decided March 19, 1980.
- Memorandum order. John Yiamouyiannis v. Marvin A. Schneiderman. U.S. District Court for the District of Columbia. Case No. 79-51, filed, Feb 9, 1980.
- Knox Working Party. Fluoridation of water and cancer: a review of the epidemiological evidence. HMSO, London, Jan 14, 1985.
- Yiamouyiannis J. Lifesavers guide to fluoridation. Risks/benefits evaluated in the 1982 question and answer report. Delaware, OH: Safe Water Foundation, 1982.
- Wulf C and others. Abuse of the Scientific Literature in an Antifluoridation Pamphlet. Columbus, OH: American Oral Health Institute, 1985, 1988.
- Hunt J and others. Putting Yiamouyiannis into perspective. British Dental Journal 179:121-123, 1995.
- Obituary: John Yiamouyiannis. Columbus Dispatch, Oct 10, 2000.
- Chowka PB. John Yiamouyiannis, PhD: A pioneering health researcher speaks out – Part two. Natural Health Village News, Oct 1, 1999.
- How is colorectal cancer staged? American Cancer Society Web site, Feb 1, 2005.
- This article was revised on July 3, 2020.