**Abstract**

Fluoride is an inorganic monatomic anion of fluorine and forms part of essential reagents used by the chemical industry. It occurs naturally in several minerals and in trace quantities in water. Fluoride has been used to prevent tooth decay and in the treatment of osteoporosis. Extensive research has consistently demonstrated the safety and effectiveness of fluorides in the prevention of dental caries following the practice of water fluoridation. Despite these benefits, fluorides pose danger as an endocrine disruptor thus, affecting bones, brain, thyroid gland, pineal gland and blood sugar levels. In Canada, water fluoridation remains a contentious issue although dental decay constitutes the most common chronic disease. However, several Canadians are receiving the benefits of water fluoridation and about 1% have access to naturally fluoridated water. In Nigeria, the prevalence of dental caries has been documented to be greatly reduced following fluoridation of public water supplies in areas where the condition was endemic. Fluoride is therefore the only medicine added to public water, and at the recommended level, fluoride is safe and effective in the reduction of dental decay and poses no risk for health problems. Hence, this article highlighted fluoride content in drinking water and the health implications of consuming fluoride-rich water with a focus on the situation in Canada and Nigeria.

**Keywords:** fluoride, water, dental decay, health
