Sometimes, fluoride can lead to low levels of thyroid hormones. This causes the pituitary gland to release more thyroid-stimulated hormone (TSH), which can cause health complications.

Iodine is responsible for proper thyroid function. However, fluoride can interfere with iodine’s ability to produce hormones in the thyroid gland. If the body cannot produce enough thyroid hormones, a person can develop hypothyroidism.

Keep reading to learn about how fluoride affects the endocrine system, pituitary gland, and pineal gland.

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The endocrine system comprises various organs and structures in the body that produce hormones. These chemicals act as messengers across the body and influence the function of other organs and structures.

Fluoride affects two glands in the endocrine system: the pituitary and pineal glands. This can have various hormonal effects:

  • TSH: Studies confirm fluoride affects the production of thyroid hormones. This drives the pituitary gland to release more TSH, which stimulates the thyroid gland in an attempt to produce more thyroid hormones.
  • Melatonin: Fluoride accumulates in the pineal gland, which produces melatonin, a hormone that is responsible for establishing sleep patterns. Some experts suggest fluoride’s effect on the pineal gland reduces the amount of melatonin produced, affecting a person’s sleep.
  • Sex hormones: Research suggests that fluoride can reduce sex hormones. Effects on sex hormones can cause problems with fertility and puberty.
  • Insulin: Another possible effect of fluoride on the endocrine system is blocking the function of the pancreas. This can affect insulin levels and how the body controls blood sugar.
  • Cortisol: Some experts suggest that fluoride also affects the adrenal glands and decreases the levels of another hormone called cortisol.

Despite having many possible effects on the endocrine system, fluoride has its place in keeping people healthy.

Fluoride may affect hormones that the pituitary gland releases.

The pituitary gland responds to thyroid-releasing hormone. This stimulates the release of TSH, which acts on the thyroid gland to release the thyroid hormones T3 and T4.

These communicate back to the pituitary gland to stop making TSH, controlling how much T3 and T4 the thyroid releases.

According to researchers, fluoride may reduce the production of T3 and T4. It interferes with iodine’s ability to produce these hormones in the thyroid gland, which can cause a condition called hypothyroidism.

With low levels of T3 and T4, people may experience:

However, in a 2018 study, researchers found that higher fluoride exposure did not result in higher TSH levels.

People with both high fluoride levels and low iodine levels tend to have higher levels of TSH. So, having adequate iodine levels in the body may bypass the effect of fluoride on the pituitary gland.

Fluoride accumulates in the pineal gland, which is at the center of the brain’s two halves. This small gland produces melatonin, a hormone that has an important role in establishing sleep patterns.

Some experts suggest that by accumulating in the pineal gland, fluoride stops the production of melatonin. However, few studies exist to confirm the effect of fluoride on melatonin and sleep patterns.

In one 2019 study, researchers explored whether high exposure to fluoride is associated with changes in sleep patterns in adolescents. The results suggest that increases in people’s exposure to fluoride through drinking water elevated the risk of sleep disturbances such as sleep apnea.

Higher fluoride exposure also affected weekday bedtime and wake time. Adolescents in the study reported getting to sleep 24 minutes later and getting out of bed about 26 minutes later.

However, despite the possible effect on different hormones, doctors and dentists still recommend fluoride due to its benefits for tooth health.

With increasing interest in the effects of fluoride on hormones, experts encourage using fluoride safely. Fluoride prevents tooth decay and cavities and is safe when used appropriately.

The Centers for Disease Control and Prevention (CDC) recommend people drink water with an optimal amount of fluoride.

Experts also recommend brushing teeth twice a day with toothpaste that contains fluoride. For children under 6 years old, a pea-sized amount of toothpaste is enough.

Fluoride toxicity may occur where drinking water contains too much fluoride, and people who receive too much fluoride may develop fluorosis. They may notice white flecks or spots or frosty edges on their teeth.

Other symptoms of fluorosis may include:

It is best for anyone who believes they may have fluoride toxicity to report their symptoms to a doctor and get a professional to test their drinking water.

Fluoride can affect some endocrine organs, such as the pituitary gland. However, people can limit the effect of fluoride on the pituitary gland by having adequate iodine in their body.

Fluoride is safe when people use it appropriately and can help prevent cavities and tooth decay.