Is fluoride in drinking water safe?
Updated: Jun 14
Fluoride is found naturally in soil, water, and foods. It is also produced synthetically for use in drinking water, toothpaste, mouthwashes and other chemical products.
In the USA, UK, Australia, NZ and a few other countries the water authorities add fluoride to the municipal water supply, because some studies have shown that adding it in areas where fluoride levels in the water are low can reduce the prevalence of tooth decay.
The following graph shows the average decayed, missing or filled teeth at age 12 from 1975 to 2014.
Most European countries, Canada, Japan and Mexico don't use fluoride in their drinking water - and they have also seen a drop in tooth decay over the years - as the below graph shows.
Concerns have arisen regarding fluoride's effect on health, including problems with bones, teeth, thyroid dysfunction and lowering of IQ in children. Causing more worries is preliminary research in laboratory animals suggesting that high levels of fluoride may be toxic to brain and nerve cells.
In June 2015, the Cochrane Collaboration—a global independent network of researchers and health care professionals known for rigorous scientific reviews of public health policies—published an analysis of 20 key studies on water fluoridation. They found that while water fluoridation is effective at reducing tooth decay among children, no studies that aimed to determine the effectiveness of water fluoridation for preventing caries [cavities] in adults met the review’s inclusion criteria.