There is no link between adding small amounts of fluoride to water and IQ levels.
Australia’s National Health and Medical Research Council (NHMRC) has been researching it for more than 60 years, and has just released its latest findings.
It began this most recent study in 2014 in the interest of “individuals and organisations who want to know more about the health effects of water fluoridation in Australia, including Australian Government decision makers, dental and other health care providers, and non-government organisations”.
“Many members of the public are also interested in this issue,” it said.
Water fluoridation is a staple issue for conspiracy theorists on the internet, and especially social media users.
There are studies – notably, one with Harvard’s assistance – that show a link between high fluoride levels and low IQ. But the common consensus is that these are widely used out of context when it comes to adding small amounts of fluoride to water supplies.
For example, the most damning evidence which opponents cite is based on research in China and India, where water in general is highly contaminated with fluoride and citizens are also susceptible to inhaling large amounts of it due to coal burning.
The more radical opponents claim fluoride was used by the Germans and Russians to pacify Jewish ghettos and prisoners of war, making individuals “docile” and “submissive”.
Still, there’s nothing wrong with keeping tabs on the situation, and that’s what the NHMRC has done every few years.
And the vast weight of evidence suggest fluoride helps reduce tooth decay, which is why it is added to water supplies.
In Australia, tooth decay is recognised as a “significant problem”, according to the NHMRC, which can cause “pain, suffering, difficulty eating and sleeping, and make people feel unhappy about their appearance”.
It says the benefits to people who can’t afford dental care and those who “find it difficult to change their behaviour and lifestyle” outweigh concerns about free choice and possible side-effects.
“Treating tooth decay is costly,” the authors note, and “most dental treatments are not covered by Medicare”.
Specifically, according to the NHMRC’s latest findings, added fluoride:
- reduces tooth decay by 26-44% in children, teenagers and adults
There is also:
- no link between water fluoridation at Australian levels and IQ or cognitive function of children or adults
- no link between water fluoridation at Australian levels and cancer overall, and
- insufficient evidence to link water fluoridation with kidney disease, kidney stones, low birth weight, thyroid problems and heart disease
But there is some:
- chance of having very mild or mild dental fluorosis – small white lines on tooth surfaces, most of which are not readily visible, have no effect on the function of teeth and often disappear with age
The NMRC has spent two years on the review. It evaluated 60 years of research, more than 3000 studies, reports and reviews, selecting and analysing them “based on their quality and relevance”.
The review was led by a team of health, dental and “other” experts who were picked based on their expertise and not their views on fluoridation. It focused only on “high quality” research and discarded studies on animals and those which allowed “self-reporting” as evidence to eliminate any possibility of confirmation bias.
It also tried to knock out instances where other factors might have contributed to low IQ levels. Higher earning, better educated people, for example, were less likely to live near contamination dangers.
And their consensus was, let’s keep adding fluoride to Australian water supplies, which, unlike those in parts of China and India, mostly have very low levels of naturally occurring fluoride – around 0.1 mg/L.
It’s why studies done in the US, South America and Africa, where levels above 3 mg/L, and China and India, where it has been recorded up to 20 mg/L, simply aren’t relevant in Australia.
The target range since 2007 in Australia has been to get fluoride levels up to 0.6 to 1.1 mg/L across the board.
In those scarce regions where fluoride levels are naturally higher – mainly some areas of central Australia – no fluoride is required to be added. Even in those places, natural fluoride levels “fall within the recommended range”.
And yes, the review took into account the extra fluoride added into systems by toothpaste and other food sources.
From a purely financial perspective, Australia is better off with fluoridated water. The review found that while the annual costs of providing water fluoridation ranged from $0.11 to $4.92 per person, the annual savings ranged from $5.49 to $93.19 per person in health care savings and lost productivity time.
For every dollar spent, an estimated $7-$18 is saved. Victoria alone saved itself, over 25 years, some $1 billion “through avoided dental costs, days away from work or school and other costs”.
And here’s an interesting take. The NHMRC also believes water fluoridation is important because it “demonstrates community solidarity”.
“We tend to think that governments should act to support good health, through ensuring things like clean air and safe foods and many people see water fluoridation in the same way.”
You can read the full report here.