The US is sounding the alarm on fluoride in drinking water - what's the story in the UK?

Fluoridation began in 1945 in Grand Rapids , Michigan , after scientists noticed people had less tooth decay in areas with naturally higher fluoride levels in the tap water.

It was first added to the water supply in England in 1964 , when a pilot scheme was launched in Birmingham .

Over the years it's been rolled out to about 75% of America 's population, compared to about 10% of England .

The WHO estimates some 400 million people in 25 countries are getting artificially fluoridated water.

Federal judge in California ordered the EPA to strengthen its regulations on fluoridation in September .

In the UK , a major review has suggested fluoridation may only have a "modest" benefit on dental caries.

The decision on whether or not add fluoride to water is ultimately made by state and local health authorities, so Mr Trump 's government can only advise them to stop it.

10% of people in England live in areas where fluoride is added to the water, mainly in the West Midlands and North East .

There is no fluoridation in Wales , Scotland or Northern Ireland .

The Conservative government introduced proposals to expand fluoridation schemes across the North East "because of the significant and long-standing inequalities in the region".