美国饮用水的氟含量太高，引发小孩的牙齿变色

The U.S. Government is expected to reduce the recommended amount of fluoride in the drinking water after finding that 41% of kids have mild fluorosis.

Fluoride in drinking water has been used since 1945 in the U.S. About 73% of Americans have access to fluoridated water provided by their municipal water supply.

Fluoride prevents tooth decay and can be vital to the proper formation of teeth in young children. Community water fluoridation has been found to be very cost effective. Savings per person found in some studies showed a range of about $16 in communities of less than 5000 people to $19 in communities with more than 20,000.

Current recommended levels of fluoride are between 0.7 and 1.2 milligrams per liter. Studies have found that these levels are safe for human consumption.

However, the recent finding that about 41% of kids have mild fluorosis is causing the federal government to decrease the recommended amount of fluoride in drinking water to 0.7 mg/l.

Fluoride and Tooth Discoloration

Fluorosis is a condition which shows spottiness and discoloration in the teeth resulting from too much exposure to fluoride. Too much fluoride can even pit teeth, the opposite of what was intended when we started fluoridating public drinking water.

Kids can get fluoride from drinking water, toothpaste, and fluoride supplements. Some places have naturally-occurring fluoride in their water.

Fluoride is not the only way to prevent cavities.  Besides limiting consumption of sticky foods, studies have found that compounds in tea, wine, and even aloe vera can help prevent tooth decay.