Dental fluorosis is a condition in which the enamel becomes progressively discolored and mottled, usually caused by excessive fluoride in the water. Researchers have linked fluorosis in children with cognitive impairment; those with higher levels of fluorosis have more cavities. Results from some studies show that lower IQ scores may result from fluoride exposure and may co-occur with fluorosis.
Fluorosis has been observed more frequently of late in children using fluoride toothpastes and drinking fluoridated water.
Research presented at the 2017 National Oral Health Conference (USA) showed that from 2011 to 2012, 57% of U.S. youth had dental fluorosis; this is a 37% increase over that reported from 1999 to 2004. Analysis of the same data by the Fluoride Action Network (FAN) showed that 58.3% of adolescents had fluorosis: 21.2% were moderately affected and 2% had a severe form of the condition.