Fluoride: myths and facts

No other toothpaste ingredient sparks as much debate. Yet fluoride is the only ingredient whose ability to reduce the risk of caries is confirmed by systematic reviews. Let's go through five myths in order.

Myth 1. "Fluoride is a poison"

Fluorine as a gas is indeed toxic. But there is none in toothpaste: it contains fluoride — an ion that is part of salts (sodium fluoride, amine fluoride, monofluorophosphate). These are different substances, just as chlorine gas differs from table salt, where chlorine is present in the form of chloride.

Toxicity is determined by the dose. To reach a dangerous dose of fluoride, an adult would have to swallow several full tubes of toothpaste at once. Normal brushing delivers only trace amounts into the body.

Myth 2. "Fluoride causes fluorosis"

Fluorosis appears as chalky-white or brownish spots on the enamel. It is indeed linked to an excess of fluoride, but with one important caveat: fluorosis is only possible while the teeth are forming — that is, roughly up to age 8, while the crowns of the permanent teeth are still mineralising under the gum.

In an adult the teeth are already formed, and fluorosis is physically impossible — regardless of the amount of toothpaste. All fluorosis concerns relate to children, which is exactly why children's toothpastes are dosed by age.

How much fluoride a child needs

Exact ppm values for each LACALUT paste can be found in the kids' section and on the packaging.

Myth 3. "Fluoride-free pastes are safer"

Fluoride-free pastes are no more dangerous — but they do not protect against caries either. Hydroxyapatite, calcium, xylitol and herbal extracts support the enamel, yet none of them replaces fluoride in terms of the evidence base: only fluoride has a proven anti-caries effect.

In a country where the water is fluoride-deficient, giving up fluoride toothpaste means being left with no working source of enamel protection at all. That is a legitimate choice, but it should be an informed one.

Myth 4. "Fluoride accumulates in the body"

Fluoride that enters the bloodstream is excreted by the kidneys — about half of the ingested dose within 24 hours. Part of it is incorporated into bone tissue, which is a normal physiological process, not "poison accumulation". Problems are possible with years of high-dose intake from drinking water (skeletal fluorosis) — a situation found in regions where the fluoride level in water is several times above the norm. This does not apply to Belarus, where the water lacks fluoride.

Myth 5. "Adults no longer need fluoride — their teeth are fully grown"

Quite the opposite. Caries is not a childhood disease: by age 35–40 virtually every adult has had it. New risk factors come with age: gum recession exposes the root, which is 2–3 times softer than enamel; medications reduce salivation; crowns and fillings with marginal gaps appear.

The WHO and national prevention programmes recommend fluoride toothpaste for life, not "until adulthood".

How to use fluoride toothpaste correctly

• Do not rinse the paste away with water. Spit out the excess and skip rinsing — this keeps fluoride on the enamel longer.
• Brush for 2 minutes, twice a day. The evening brushing matters more than the morning one: less saliva is produced at night.
• Do not let small children use toothpaste unsupervised. It is not about toxicity — the dosage is designed for spitting out.
• Look for the ppm on the packaging. If the manufacturer does not state the concentration, that is a reason to be wary.