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Ong Ye Kung says fluoride in S'pore water at only 0.45mg/litre on average, addresses US study on fluoride & low IQ link in children
Ong also explained the importance of fluoride in water.
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Health Minister Ong Ye Kung addressed a recent controversial U.S. study that posited a link between higher fluoride levels in water and lower IQ in children, while assuring the public that water in Singapore is safe for consumption.
In a Facebook post on Jan. 30, Ong said the mandated level of fluoride in treated water in Singapore shall be no more than 0.7mg/litre.
"Actual levels in our water supply range between 0.2 and 0.56mg/litre, with an average of 0.45mg/litre over the past year," Ong said.
He noted that the study did not find a detected effect below 1.5mg/litre, which aligns with the recommended maximum fluoride level in drinking water by the World Health Organisation (WHO).
Importance of adding fluoride to water
In his post, Ong also highlighted the importance of adding the mineral to water.
"Fluoride is added to tap water in many countries worldwide. In Singapore, the practice started in 1957," he said.
Fluoridation of water's main purpose is to protect teeth, reduce tooth decay, and prevent its associated complications.
If tooth decay is left untreated, it can lead to serious issues, including the development of painful abscesses, Ong noted.
Once an abscess forms, it can only be treated with root canal treatment, surgery or extraction of the affected tooth.
Ong then concluded his post by pointing out that excessive consumption of any chemical is always bad for health.
"Harmful chemicals are most common in polluted air, cigarettes, e-cigarettes, highly processed food, which we already know are harmful to us," he added.
He concluded: "For others, we control the levels to where it benefits us. Such is the case for fluoride in tap water."
Study: Link between higher fluoride levels and lower IQ at 1.5mg/litre is "uncertain"
The study that caused a stir was published on Jan. 6, 2025, in the Journal Of The American Medical Association Paediatrics.
In its findings, the study noted there was "limited data and uncertainty" between higher levels of fluoride and lower IQ in children at a level below 1.5mg/litre.
The publication of the study was considered significant, however, as it was done ahead of the inauguration of U.S. President Donald Trump.
Trump nominated Robert F. Kennedy Jr. as Health Secretary.
Apart from being a vaccine sceptic and an advocate of raw milk, Kennedy has called for the removal of fluoride from drinking water across the country, Reuters reported.
What is fluoride?
Fluoride is a mineral that occurs naturally in water, soil and air that has been demonstrated to prevent dental cavities, or tooth decay, Reuters explained.
It works by strengthening the tooth's hard outer surface, known as enamel.
Fluoride makes teeth more resistant to the acid produced by bacteria that causes tooth decay.
Fluoride also reverses early tooth decay by replacing and preventing loss of minerals in teeth.
What study said
Researchers at the U.S. National Institutes of Health (NIH) found IQs were lower in children with higher fluoride exposure after analysing 74 studies from 10 countries.
In four studies with a low risk of bias involving 4,179 children, urinary fluoride concentrations at levels reportedly common in developed countries were associated with lower IQ score.
However, multiple weaknesses of the NIH analyses were subsequently found and it was warned that public policy concerning fluoride "should not be affected by the study findings".
Top photo via Ong Ye Kung/Facebook
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