Trump’s pick for health secretary has many dangerous views – but some good ideas, too | Devi Sridhar

The United States and Britain: two countries divided by a common language and by very different approaches to health, whether it’s how healthcare is accessed, what kind of food products are sold in supermarkets, what is advertised on TV or even what is in the water that we drink from our taps. Having lived in both countries for an extensive period, the UK, in my opinion, takes a more sensible approach to implementing pro-health and wellbeing policies, closely linked to EU regulations. But the US could soon be following suit, under a range of proposals from a surprising source: Donald Trump’s nominee for health secretary, Robert F Kennedy Jr. As I laid out last month, many of his ideas are potentially dangerous for public health – from bizarre conspiracy theories to anti-vaccineviews and campaigning – and completely divorced from data and reality. But a couple of them could turn out to be beneficial.

For example, the US still allows certain additives banned by the UK and EUto be added to ultra-processed foods such as cereals, sweets and biscuits, despite the fact that they have been linked to hyperactivity in children. Kennedy has suggested this week that he will ban some of these in food products. Depending on what exactly he does, this isn’t a radical suggestion: it may just put the US in line with what is done in other countries. It’s the same with his suggestions to regulate the advertising of pharmaceutical products and improve the nutritional quality of school meals.

But what about his pronouncements about the dangers of fluoride in drinking water? In 1945, fluoride was introduced into US drinking water because of concerns about dental health and the rise of cavities in children. Fluoride is a naturally occurring mineral and is proven to reduce tooth decay. And the evidence does show that fluoridated water has important dental health benefits.

Kennedy has vowed to remove fluoride from drinking water, claiming it is toxic. Yes, at high levels and when ingested (rather than just applied to teeth like toothpaste), fluoride can be toxic to the brain and can adversely affect the cognitive development of children – a recent Jama Pediatrics meta-analysis (which summarises other studies) showed that high levels of fluoride exposure were linked to lower IQ scores in children. Yet the point at which fluoride affects neural development is far higher than the level found in average US tap water. It is also above the level that the World Health Organization recommends as the maximum allowable concentration in drinking water. In addition, the Jama Pediatrics article was published with two expert commentaries noting that the meta-analysis findings were limited – of the 74 studies included, 45 were conducted in China – and 52 studies were highlighted as having a high risk of bias.

As with most things in science, fluoride isn’t absolutely good or bad. It was a tool brought in to help reduce dental problems – which it did effectively – and it’s worth constantly re-examining that policy to evaluate whether it fits with the latest evidence and state of the world.

Does the US still need fluoride in the water? That depends on who you ask: we now have better ways of preventing tooth decay, such as seeing a dentist regularly, brushing with fluoride toothpaste, flossing and limiting sugary foods and drinks that get stuck in teeth and encourage bacterial growth. However, dentists are increasingly out of reach for struggling families and children in deprived areas. Some countries are still moving towards adding fluoride: England and Wales introduced a bill in 2021 to allow the health secretary to bring in water fluoridation – supported by all four nations’ chief medical officers. It’s estimated that about one in 10 people in England have fluoridated drinking water, with plans to expand it further.

Ending water fluoridation in the US would not be a major concern for me as a public health scientist – as long as dentists are made accessible. That said, Kennedy making unfounded claims that fluoride causes thyroid disease and cancer doesn’t help inform the real public debate over fluoridation.

I’m more focused on whether he maintains the childhood vaccination schedule (for example against measles, whooping cough and mumps) and whether he is able to bring the US in line with the UK and the EU in terms of what is permitted to be added to foods that we buy from our shops. This might mean saying adios to the artificial food dyes used in cereals such as Froot Loops and Lucky Charms, but if it means parents being able to buy food products checked for safety for their children and healthier school lunches, that’s a huge step forward, no matter who initiates it.

• Prof Devi Sridhar is chair of global public health at the University of Edinburgh

• Do you have an opinion on the issues raised in this article? If you would like to submit a response of up to 300 words by email to be considered for publication in our letters section, please click here.