{"id":280877,"date":"2025-11-13T02:59:12","date_gmt":"2025-11-13T02:59:12","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/280877\/"},"modified":"2025-11-13T02:59:12","modified_gmt":"2025-11-13T02:59:12","slug":"what-exactly-is-fluoride-and-why-is-it-added-to-our-tap-water","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/280877\/","title":{"rendered":"What exactly is fluoride, and why is it added to our tap water?"},"content":{"rendered":"

With more councils voting to remove<\/a> fluoride from drinking water recently, it’s worth revisiting exactly why was added in the first place.<\/p>\n

So what is fluoride, how does it work \u2014 and if you don’t have access to fluoridated water, what else can you do to protect your teeth?<\/p>\n

What is fluoride?<\/p>\n

Fluoride is a form of the element fluorine: fluoride ions are fluorine atoms with an extra electron, making them negatively charged.<\/p>\n

Fluoride ions occur naturally in rocks and minerals, and from there they dissolve easily into water, according to Laurence Walsh, a dentistry researcher at the University of Queensland.<\/p>\n

“You find fluoride ions in all water sources, including lakes, rivers and in the ocean,” Professor Walsh says.<\/p>\n

A number of food and drinks also contain fluoride, particularly tea, cereals, grains, apples, almonds and milk.<\/p>\n

Some areas have naturally elevated levels of fluoride in their water supplies, which is how researchers first realised fluoride could improve dental health.<\/p>\n

In the early 20th century, researchers noticed residents of certain US towns<\/a> had unusually low cavity rates, despite having dark stains on their teeth.<\/p>\n

Both the low cavities and the stains came from high fluoride levels in the water supply \u2014 higher than the levels at which it’s added artificially today.<\/p>\n

What does it do in our bodies?<\/p>\n

In the mouth, fluoride gets added to the outer layer of our teeth, the enamel.<\/p>\n

Enamel is constantly worn down by acidic drinks and bacteria, and built back up by saliva in a process called “remineralisation”.<\/p>\n

Professor Walsh says that a can of soft drink can erode about one fiftieth of a millimetre of tooth enamel.<\/p>\n

“It takes the saliva about two days to redeposit that mineral on the tooth.”<\/p>\n

\"Teeth<\/p>\n

The outer layer of your teeth is constantly being worn down by food and bacteria, and replenished by your saliva. (Unsplash: Ozkan Guner)<\/p>\n

When fluoride is present in saliva, it makes the remineralised material stronger.<\/p>\n

“Fluoride combines with calcium and with phosphate to form a very rigid mineral,” Professor Walsh says.<\/p>\n

The fluoride-containing mineral is more resistant to acids than enamel would be on its own.<\/p>\n

Virginia Dickson-Swift, a public health researcher at La Trobe University, says fluoride can reverse early decay in the mouth.<\/p>\n

“It’s kind of a repair tool if you think about it, almost like a puncture kit,” Dr Dickson-Swift says.<\/p>\n

When ingested, it can also be incorporated into bones in the same way, but most fluoride passes harmlessly through the body and is excreted.<\/p>\n

At high amounts \u2014 well above the amount added to drinking water in Australia \u2014 fluoride can cause a condition called fluorosis.<\/p>\n

Mild dental fluorosis causes stains on teeth in children, and when it’s severe it can cause bone weakness.<\/p>\n

\"Closeup<\/p>\n

Other than discolouration, mild dental fluorosis doesn’t have any side effects. (Wikimedia Commons: Matthew Ferguson 57, CC BY-SA 4.0<\/a>)<\/p>\n

But fluoride levels in water need to be high for this to happen: above 10 milligrams per litre (or 10 parts per million) to risk severe fluorosis, and above 1.5 milligrams per litre to risk mild tooth staining, according to the \u00a0World Health Organization guidelines<\/a>.<\/p>\n

In Australia, \u00a0the National Health and Medical Research Council recommends<\/a> fluoride levels stay between 0.6 and 1.1 milligrams per litre.<\/p>\n

What’s the evidence on fluoride and tooth health?<\/p>\n

When fluoride is added to tap water, communities reliably see a drop in cavities or tooth decay (known by dentists as ‘caries’).<\/p>\n

Professor Walsh says more than 70 studies have tracked long-term dental health in communities after water is fluoridated.<\/p>\n

“What they show consistently is the severity of decay goes down by over a third.”<\/p>\n

Several studies<\/a> run in Australia have reflected<\/a> this decrease<\/a>, particularly in Queensland<\/a>.<\/p>\n

\"A<\/p>\n

While there are other sources of fluoride, tap water is a consistent way to add it to everyone’s diet. (Unsplash: Jacek Dylag)<\/p>\n

Children’s hospital admissions also go down, according to Dr Dickson-Swift, because of reduced rates of things like dental abscesses.<\/p>\n

Dr Dickson-Swift adds these changes can sometimes be seen in a matter of years.<\/p>\n

“In Victoria, one of the latest communities we had fluoridated was Cohuna, and we’ve seen a change in the dental caries [cavity] rates in three years.”<\/p>\n

Queensland’s bizarre health debate<\/a><\/p>\n

Many people would say the benefits of fluoride in water are clear but in this state it’s often not there and there will be lasting health impacts.<\/p>\n

And when fluoride is removed from a water source, numbers move in the other direction.<\/p>\n

“When we take fluoride out of the water, we can see a clear pathway to those things going up. We certainly seen that in Queensland,” Dr Dickson-Swift says.<\/p>\n

This effect has also been seen overseas, such as one study<\/a> which compared two cities in the Canadian province of Alberta \u2014 one that stopped fluoridating water, and one that didn’t.<\/p>\n

Children in the non-fluoridated city had consistently higher decay rates.<\/p>\n

How do I know if I have fluoridated water?<\/p>\n

Dr Dickson-Swift advises checking with your local council to see if your water source is fluoridated.<\/p>\n

“One of the biggest things that I’ve found in communities that I’ve been working in over the years is many communities don’t know whether their water is fluoridated or not,” she says.<\/p>\n

“So they’re not actually making informed decisions about how they look after their oral health.”<\/p>\n

Most Australians live in areas with fluoridated water, but not all \u2014 particularly in Queensland, where most councils have voted to remove it.<\/p>\n

If you use a rainwater tank instead of mains water, you also won’t have fluoridated water.<\/p>\n

Bottled water doesn’t necessarily have fluoride in it. Bottled water can contain some naturally occurring fluoride, but if it’s added, it must be labelled in Australia.<\/p>\n

Will my water filter remove fluoride?<\/p>\n

It depends upon which type of filter your water jug uses.<\/p>\n

Oliver Jones, a chemist at RMIT University, says most off-the-shelf water filters won’t remove fluoride.<\/p>\n

“If you use something like granular activated carbon, which is a common filter, that doesn’t actually take fluoride out very easily,” Professor Jones says.<\/p>\n

But some, like ion exchange filters, can remove fluoride.<\/p>\n

\"Person<\/p>\n

Most off-the-shelf jug filters won’t remove fluoride. (Getty Images: Ekaterina Vasileva-Bagler)<\/p>\n

Can you keep your teeth healthy without fluoridated water?<\/p>\n

If you don’t have access to fluoridated water, or you’re losing access, your teeth aren’t inevitably going to get worse \u2014 but you will need to be more careful to keep them healthy.<\/p>\n

“It’s going to increase your risk. So that means you need to increase your prevention,” Professor Walsh says.<\/p>\n

He says good brushing habits, and lowering sources of sugar and acid in your diet, can both lower your risk of dental decay.<\/p>\n

The simplest intervention, Dr Dickson-Swift says, is to brush your teeth with a fluoride toothpaste twice a day \u2014 and avoid rinsing your mouth out afterwards.<\/p>\n

“The minute you rinse your mouth, you’re rinsing the fluoride off your teeth.”<\/p>\n

\"A<\/p>\n

Good tooth brushing habits can make up for losing fluoride in the water supply. (Unsplash: Joshua Hoehne)<\/p>\n

She also recommends heading to your state government website for advice on dental health.<\/p>\n

If you’re choosing between toothpastes, Professor Walsh recommends opting for a toothpaste with stannous fluoride (also called tin fluoride).<\/p>\n

In addition to protecting teeth, this compound has antibacterial properties.<\/p>\n

He also recommends regular dentist visits to identify any signs of decay early.<\/p>\n

Access to dental health a priority<\/p>\n

Dentists can do specific protective treatments, such as fluoride varnishes, which can help to prevent decay.<\/p>\n

“We don’t have an instant replacement for fluoride in water, but we’ve got a range of things that at the individual level can be tailored to somebody’s lifestyle and to their risk to make sure that it is appropriate,” Professor Walsh says.<\/p>\n

\"A<\/p>\n

Dr Dickson-Swift says dental health initiatives often miss communities where the need is greatest. (Unsplash: Bob van Aubel)<\/p>\n

This does, of course, assume you have the time and money to get to the dentist.<\/p>\n

“In a lot of communities that I talk to, it is the most disadvantaged people who are missing out,” Dr Dickson-Swift says.<\/p>\n

“There’s no fluoride in the water there, people are on low incomes, they’re living in areas of disadvantage without dental services.”<\/p>\n

Dr Dickson-Swift says that broader scale education programs on tooth brushing have been helpful in these areas.<\/p>\n

“There’s a lot of oral health promotion and oral health education work that can be done within communities so that people have the information that they need to then make informed choices.”<\/p>\n

She believes dental health should be included more widely in council health initiatives, alongside healthy eating and exercise promotion.<\/p>\n

“We don’t connect the healthy body with a healthy mouth.”<\/p>\n","protected":false},"excerpt":{"rendered":"With more councils voting to remove fluoride from drinking water recently, it’s worth revisiting exactly why was added…\n","protected":false},"author":2,"featured_media":280878,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[64,63,12608,162562,25155,21828,110253,162559,137,1836,11787,96957,162558,162560,162563,162561,162564],"class_list":["post-280877","post","type-post","status-publish","format-standard","has-post-thumbnail","category-health","tag-au","tag-australia","tag-dental-health","tag-does-fluoride-prevent-dental-caries","tag-drinking-water","tag-fluoride","tag-fluoride-in-water","tag-fluorosis","tag-health","tag-public-health","tag-teeth","tag-tooth-decay","tag-water-fluoridation","tag-what-is-fluoride","tag-what-should-i-look-for-in-a-toothpaste","tag-why-is-fluoride-put-in-tap-water","tag-will-water-filters-remove-fluoride"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/280877","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=280877"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/280877\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/280878"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=280877"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=280877"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=280877"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}