The question of whether or not to fluoridate public water creates a good amount of controversy. Supporters of fluoridated water site the prevention of tooth decay as the key benefit. However, many wonder if better dental health is worth the risks that fluoride presents to the endocrine system.
The endocrine system is a group of glands that manufacture and secrete hormones, chemicals which are important for growth, metabolism, and the development and function of sex organs. The major glands that make up the endocrine system include the adrenal glands, the hypothalamus, the pancreas, the pineal gland, the pituitary gland, the parathyroid gland, the thyroid gland and the ovaries and testes.
Chemicals that interfere with the endocrine system are called endocrine disruptors. According to a report put out by the National Research Council in 2006, fluoride is one such chemical. Here are three ways excessive fluoride from drinking water and other sources may affect the endocrine system:
- Fluoride may alter function of the pineal gland. Located near the center of the brain, the pineal gland is a tiny pinecone-shaped organ that secretes one hormone only—melatonin. This hormone helps regulate reproductive hormones and circadian rhythms (or sleep-wake patterns). Deposits of fluoride and other chemicals in the pineal gland over time cause calcification. Studies show pineal gland calcification is linked to a disturbed sense of direction, Alzheimer's disease, and it is likely to reduce production of melatonin.
- Fluoride displaces iodine from human cells. This is particularly important to cells of the thyroid gland, a part of the endocrine system that needs iodine to function properly. Iodine plays a part in the manufacture of the thyroid hormones thyroxine (T4) and triiodothyronine (T3), which are regulated by thyroid-stimulating hormone (TSH). The report by the National Research Council found that human exposure to fluoride showed increased levels of TSH, altered levels of T3 and T4 and a higher prevalence of goiters (swelling of the thyroid gland).
- Fluoride may affect testosterone production. Many animal studies have shown that exposure to fluoride can create a number of conditions that impair production of testicular testosterone. These conditions include weakened enzyme function, increased oxidative stress, blockage of androgen receptors and cell damage.
Many people rely on fluoride to keep teeth strong and healthy, however too many sources may result in excessive amounts. Fluoride is found in many city and state water supplies, food and beverage products manufactured with this water, dental products like toothpaste and mouthwash, and prescribed drops and rinses. With growing evidence of the damage fluoride does to the endocrine system, people may want to evaluate the amounts they ingest on a regular basis.