You have probably seen the headlines. "Fluoride causes cancer." It pops up on social media, in alternative health blogs, and in whispered conversations at the health food store. But is there any real truth behind it?

The short answer is no — not according to the weight of scientific evidence. Organisations like the National Cancer Institute, the World Health Organisation, and Public Health England have all reviewed the research and found no credible link between fluoride at the levels used in community water fluoridation and cancer risk.

One of the largest reviews was carried out in 1990 by the US National Toxicology Program. It found no evidence that sodium fluoride caused cancer in humans. More recent systematic reviews have reached the same conclusion.

The confusion often arises from mixing up different types of exposure. The fluoride used in water supplies is at very low concentrations — around 0.7 mg per litre in the UK. This is nothing like the high doses studied in laboratory settings that sometimes raised questions.

Fluoride helps teeth in a very practical way. It strengthens tooth enamel, making it more resistant to decay. Decayed teeth are painful, expensive to treat, and entirely preventable. The NHS and dental professionals across the UK continue to recommend fluoride because the benefits are clear and the risks at recommended levels are essentially non-existent.

If you have concerns about fluoride, bring them up at your next appointment. Your dentist can explain what fluoride levels are in your local water supply and whether additional fluoride would benefit you or your family.

The evidence on fluoride and cancer is reassuring. Do not let scare stories on the internet put you off something that genuinely protects your teeth.