1) damage to teeth, known as dental fluorosis;
2) weakening bones and connective tissue, calcifying cartilage and ligaments;
3) fluoride competing with iodine, thus damaging thyroid function;
4) causing arthritic symptoms (in extreme exposure, “crippling skeletal fluorosis”);
5) calcification of the kidneys, and of the pineal gland which makes a key hormone, melatonin; and
6) causing a rare but deadly form of bone cancer, osteosarcoma, which can afflict – and often kill – boys and young men.
Hardly a nutrient to be sought after and recommended, fluoride is a poison to be avoided, ranking as more toxic than lead and not quite as toxic as arsenic.