Positivity on the topic of water fluoridation is growing on Twitter where the number of supporters has grown from nil to 19% in five years.

By contrast, Facebook is a platform where opposition to water fluoridation has remained constant.

These are among the conclusions drawn from a paper which compares identical studies analysing social media accounts on Twitter and Facebook. Carried out five years apart, in 2015 and 2021, the studies looked at the public’s perception of water fluoridation as expressed on social media. Accounts were divided into three groups, supportive, anti or neutral to water fluoridation.

BFS member Rebecca Linney undertook the 2015 study as part of her dental degree to understand how social media was being used by campaigners. She was fascinated by the topic because she comes from Liverpool where the water is not fluoridated but undertook her dental degree in fluoridated Birmingham.

In March of this year Linney repeated the study to test whether there had been a change in perceptions. A key finding of her comparison is that today, 19% of Twitter accounts featuring water fluoridation support the public health measure whereas in 2015 there were no pro water fluoridation accounts at all.

It’s a topic which invokes strong feelings, with libertarians opposing the view that fluoride should be added to drinking water supplies alongside other chemicals that prevent disease, such as chlorine, which protects from cholera and typhoid. This is counter to the view of most healthcare organisations, especially dental, which support all measures designed to improve health through universal measures.

Dr Linney’s other key findings are:

• Facebook continues to be the platform where there is most negativity around water fluoridation
• The number of anti water fluoridation pages on Facebook has increased but the number of anti water fluoridation groups has decreased
• There are more pro-fluoridation events on Facebook
• Today there are fewer Twitter accounts which could be described as uncategorised or neutral in relation to water fluoridation.

Dr Linney said: ‘I was particularly interested to see that there are more events supporting water fluoridation listed on Facebook, indicative of an upsurge of commitment to promoting water fluoridation.

‘I can also see that there is now more support on Twitter thanks to the British Fluoridation Society, Public Health England, the Oral Health Foundation and many more organisations using their accounts to post informative statements and links.’

Barry Cockcroft, Chairman of British Fluoridation Society added: ‘This paper is really useful in understanding how important it is to continue to communicate clear and scientific statements about water fluoridation. The fact is, unless we keep active on social media, opponents will fill that vacuum. This is a most valuable piece of work.’

*Original article online at https://doi.org/10.1038/s41404-021-0781-9