Fluoride is an extremely toxic substance, yet for decades it has been promoted as “good for teeth.” The evidence supporting this claim is weak, while evidence of harm is extensive and growing.
Fluoride has long been linked to dental fluorosis, brittle bones, thyroid issues and other health problems. More recently, studies have connected fluoride exposure to reduced IQ and behavioural issues in children. In September 2024, a U.S. federal court ruled that water fluoridation at current levels poses an “unreasonable risk” of lowering children’s intelligence.
Health agencies have always known fluoride should not be swallowed. Fluoride toothpaste in New Zealand carries warnings advising against use by young children, and in the United States since 1997, all toothpaste tubes have been required to carry the label: “Keep out of reach of children under 6 years of age. If more than used for brushing is accidentally swallowed, get medical help or contact a Poison Control Centre right away.”
Only about 4% of the world’s population receives fluoridated water, with numbers steadily declining. The United States accounts for more than half of that total, yet even there, entire states such as Utah and most recently Florida, have rejected the practice.
In New Zealand, one of the most qualified voices on the issue was the late Dr John Colquhoun. A dental surgeon and Auckland’s former Principal Dental Officer, Dr Colquhoun began as a strong supporter of fluoridation and even promoted it as a city councillor. However, after extensive international research, he reversed his position and in 1997 published Why I Changed My Mind About Water Fluoridation. He later expressed regret at having once promoted it.
Fluoride Free NZ continues to highlight research and historical evidence challenging the safety of fluoridation. Their website, https://fluoridefree.org.nz/
contains a wealth of resources including Dr Colquhoun’s influential work.
The question remains: in light of mounting scientific and legal evidence, why do New Zealand officials still insist on adding fluoride to our drinking water?
















