Reacting to a new study published in the US Journal of the American Medical Association (JAMA) Paediatrics that purports to link higher exposure of fluoride in water to lower IQ in children, Professor Grant McIntyre, Dean of the Faculty of Dental Surgery at the Royal College of Surgeons of Edinburgh said:
“This study should not be regarded as providing any proof that fluoridation in water is harmful. On the contrary, there is overwhelming evidence to show that fluoridation has huge public health benefits.
Even the study’s authors admit there are flaws in the report's methodology. For example, whilst the study analysed data from 74 studies conducted in 10 countries, 52 of these studies were in their view of “low quality.” Indeed, the report’s authors themselves acknowledge that “there is not enough data to determine if 0.7 mg/L of fluoride exposure in drinking water affected children’s IQ.
Furthermore, almost all of these studies were done in settings where other contaminants, such as coal pollution in China, were present and based single-point urine samples instead of 24-hour collections which provide greater accuracy.
Fluoride is a naturally occurring mineral found in soil, food, and drink and also in drinking water supplies that helps restore minerals lost to acid breakdown in teeth, reduces acid production by cavity-causing bacteria, and makes it harder for these bacteria to stick to the teeth.
“In some parts of England, local geology means that the level of fluoride in public water is already at the level (1mg/l) that fluoridation schemes run at. This, one should note, is well below the World Health Organization’s safety limit of 1.5mg/l.
Not all parts of the UK have fluoridation, but the public health benefits are clear. For instance, Public Health England estimate that if all 5-year-olds in England drinking water with 0.2mg/l of fluoride instead received fluoridated water of at least 0.7mg/l, then the number experiencing decay would fall by 17% in the least deprived areas, rising to 28% in the most deprived areas.
We are therefore confident that fluoridation is safe and has significant benefits to public health in reducing tooth decay, particularly in more deprived areas. Indeed, a further benefit of water fluoridation over other approaches is that it does not rely on behaviour change, which is particularly important for children and vulnerable groups.”