Written by Dr. Cristian Dunker, BDSc, MBA
The question of whether fluoride in drinking water causes cancer is one that comes up often, and understandably so. When it comes to something as basic as the water we drink, people want to know the facts. So let's look at what the scientific evidence actually says.
The short answer: decades of research from major health organisations around the world have found no reliable evidence that water fluoridation at recommended levels causes cancer or other serious health problems.
What Is Fluoride and Why Is It in Our Water?
Fluorine is one of the most abundant elements on earth, and fluoride (its ionic form) occurs naturally in soil, water, and many foods. It's also found naturally in your teeth and bones.
Water fluoridation is the process of adjusting the natural fluoride level in drinking water to a concentration that helps prevent tooth decay. In Australia, the National Health and Medical Research Council (NHMRC) recommends a concentration between 0.6 and 1.1 mg/L, depending on climate.
Fluoridation has been practiced in Australia since 1953 and is widely considered one of the most effective public health measures for reducing dental caries across all age groups.
What Do Major Health Organisations Say?
Over the past 30+ years, the fluoride and cancer question has been investigated by some of the most respected health bodies in the world, including:
The International Agency for Research on Cancer (IARC)
The US National Cancer Institute
The World Health Organization (WHO)
Australia's National Health and Medical Research Council (NHMRC)
The European Scientific Committee on Health and Environmental Risks
The Royal Society of New Zealand
None of these organisations have found a causal link between water fluoridation at recommended levels and cancer.
The NHMRC Review (2017)
In 2017, the NHMRC published one of the most thorough reviews of water fluoridation evidence to date. Their key findings included:
Water fluoridation reduces the incidence of tooth decay in both children and adults
There is no reliable evidence that fluoridation at Australian levels causes health problems
No established link was found between fluoridation and cancer, Down syndrome, cognitive impairment, hip fractures, or chronic diseases like kidney disease or hypertension
Some cases of mild dental fluorosis were observed, but these were cosmetic (faint white lines on teeth) and not considered a health concern
The full NHMRC review is available through the Australian Government's health research database.
What About Osteosarcoma?
One specific concern that has received attention is a possible link between fluoride exposure and osteosarcoma (a type of bone cancer). This concern arose partly because fluoride accumulates in bone tissue, and osteosarcoma develops in growing bone.
A 2016 controlled study in the United States identified a potential association between childhood fluoride exposure and osteosarcoma in boys, though notably not in girls. However, a separate study conducted in Texas the same year found no relationship between water fluoridation levels and osteosarcoma rates in either children or adults.
The current scientific consensus, as stated by the National Cancer Institute, is that the evidence does not support a link between fluoride exposure and increased cancer risk.
Is Fluoride Safe for My Family?
At the levels used in Australian water supplies (0.6 to 1.1 mg/L), fluoride is considered safe for people of all ages, including children and pregnant women. It's one of the most studied public health interventions in history, and the evidence consistently supports its safety and effectiveness.
That said, it's worth being mindful of total fluoride intake in young children. Using only a pea-sized amount of fluoride toothpaste for kids under six, and making sure they spit rather than swallow, helps keep their exposure within safe limits.
The Benefits of Fluoride for Your Teeth
Fluoride works in two main ways:
Strengthening enamel: It integrates into the tooth structure, making it more resistant to acid attacks from bacteria and sugars
Remineralisation: It helps repair early stages of tooth decay by encouraging minerals to return to areas where enamel has been weakened
For patients who are at higher risk of cavities, your dentist may recommend additional fluoride treatments such as professional-strength rinses or varnishes.
The Bottom Line
It's natural to have questions about what goes into your water and how it affects your health. The evidence from decades of research across multiple countries and health organisations is reassuring: water fluoridation at recommended levels does not cause cancer and remains one of the most effective ways to prevent tooth decay across entire communities.
If you have questions about fluoride, your dental health, or anything else, our team at ArtSmiles in Southport is always happy to chat. We believe in giving you clear, honest information so you can make informed decisions about your care. Book an appointment or call us on (07) 5588 3677.