John Yiamouyiannis, Ph.D. (1945-2000) was the most prominent opponent of water fluoridation in the United States until his death in 2000. He is the author of the book Fluoride, the Aging Factor, the pamphlet A Lifesaver's Guide to Fluoridation, as well as the co-author (with Peter Duesberg) of AIDS: The Good News Is HIV Doesn't Cause It.
He was best known for being the "go-to" person for those trying to stop fluoridation in their communities. Originally he had been the biochemical editor at Chemical Abstracts Service, where he became convinced fluoridation was dangerous. He was the "science director" of the National Health Federation (an anti-fluoride, pro-quackery advocacy group) from 1974 to 1980, who hired him to "break the back of promoters' efforts to fluoridate more American cities." His pamphlet "A Lifesaver's Guide to Fluoridation" was usually distributed by opponents anywhere where fluoride was being considered, and Yiamouyiannis was often called to testify before local city councils and county boards in opposition. In 1980 he left the National Health Federation to start his own anti-fluoridation advocacy group, the National Health Action Committee. His claims - fluoride causes cancer, speeds up the aging process, causes bone deterioration, etc. have been disproven (at least in the low levels in municipal water supplies) by many scientific studies yet he persisted in them. In the early 1990s he found another angle to use, an environmentalist one: fluoridation was a plot by industries such as ALCOA to dispose of their toxic waste by putting it in our drinking water.
He also ran for President in 1992 as an independent but was only on the ballot in a few states. He died of colorectal cancer in 2000, which he chose to have treated in several Mexican clinics with laetrile and vitamins instead of seeking conventional treatment. Colorectal cancer has a 95% chance of survival beyond 5 years if caught early and properly treated using scientifically proven methods.
Since his death the anti-fluoridation movement has passed on to others and his work and name have become much less prominent - to the point that Wikipedia does not (yet) even have an article about him.