Water purification is one of the many basic advantages of living in an advanced culture. In the 20th century, many governments decided to start supplementing the drinking water they provide with fluorides in order to control tooth decay among the general population. The decision on whether to implement fluoridation in major cities in the United States is left up to the local government. However, there are very few municipal water treatment plants that do not practice fluoridation, and every major city in the country has opted in. About 67% of all Americans receive fluoridated water from their tap.

Despite its focus on the well being of the general population, many people are opposed to the fluoridation of water by the government. They cite lack in substantial research, cost effectiveness, supposed health risks, and an unwillingness to submit to mass medication as reasons to oppose the additives. Some developed countries have abandoned the practice.