Focus on Fluoride
The Ministry of Health has a section on frequently asked questions about fluoride and water fluoridation in New Zealand on their website www.moh.govt.nz.
Here is an extract below of their answers. For further information visit the site.
Q. Is there a difference between fluoride found naturally in water and fluoride that is added to water?
A. The fluoride ions in water are exactly the same regardless of whether they come naturally from rocks or are added as calcium fluoride or sodium silicofluoride. The dental benefits of fluoridated
water occur no matter the source of the fluoride.
Q. Is non-fluoridated water more pure than fluoridated water?
A. No. All natural waters contain many different minerals and compounds, including fluoride. The amount of each mineral and compound depends on where the water comes from. Fluoride occurs naturally in most waters and cannot be considered an impurity. This was confirmed by a Privy Council decision in 1963 that stated ‘the addition of fluoride adds no impurity and the water remains not only water but pure water and becomes greatly improved and still natural water containing no foreign elements’.
Q. How does fluoride help teeth?
A. Fluoride works in three ways.
• Fluoride makes teeth more resistant to decay by strengthening the tooth surface.
• Fluoride interferes with the growth of the bacteria that cause cavities.
• Fluoride helps to repair the early stages of tooth decay.
Fluoride can help strengthen baby teeth before they come through the gums by building fluoride into their structure. The main effect is when teeth erupt through the gums. If fluoride is present in saliva, teeth will continually be exposed to small levels of fluoride,
which helps strengthen the tooth surface. Fluoridated water is the best way to achieve this.
Q. Where else can I get fluoride from?
A. Common sources of fluoride for people include food and drink, toothpaste and fluoride
supplements such as tablets.
Some countries use fluoridated salt, others fluoridated milk. The World Health Organization says
fluoridated water is the most effective and safest way of providing the benefits of fluoride.
Q. Do fluoride tablets work as well as fluoridated water?
A. No. The benefit of fluoride tablets is limited as they don’t provide constant small doses throughout the day and are more expensive over time than water fluoridation. The fluoride in the saliva from a tablet lasts only three hours, and would give less than 1 percent of the fluoride available from food and drink in a fluoridated area. To be effective, fluoride tablets must be taken every day and preferably chewed. Even well motivated parents can find it difficult to ensure children receive tablets regularly. At a public research level, water fluoridation is more effective because it is taken regularly throughout the day in the water used to drink and cook with irrespective of the consumer’s social, economic or
physical status.
Q. Does fluoridation cause health problems?
A. The weight of scientific evidence supporting the safety and effectiveness of fluoridation is overwhelming and it is clear the majority of reputable health, scientific and medical bodies agree
with its use. Many parts of the world have received naturally fluoridated water for thousands of years. Large human populations have now been exposed to community water fluoridation for many decades and no persuasive evidence links optimal fluoridation with any adverse health effects. With hundreds of millions of people continuing to receive the benefits of fluoride in drinking-water, the absence of documented adverse health effects is particularly convincing.
Q. What is the benefit of fluoride to teeth when it is ingested instead of applied topically?
A. Fluoride ingested and applied topically, such as drinking-water and brushing teeth with a fluoridated toothpaste, go hand in hand as effective measures to help prevent tooth decay. Sugar intake constantly flowing past teeth needs good levels of fluoride in plaque and saliva to be the ‘first line’ in fluoride prevention.
Human beings are well adapted to living in an environment with natural fluoride. Some of the fluoride we ingest is taken up by bones and teeth. The fluoride taken in to the teeth also helps to
prevent dental decay by strengthening the teeth and reducing enamel demineralisation.
Our kidneys excrete excessive fluoride from the body, so to protect teeth over our lifetime it is important to have small, regular amounts such as is provided in fluoridated water and fluoridated toothpaste. When fluoride is ingested regularly when teeth are developing, it is deposited across the tooth’s entire surface and this slows down decay. Because of this, tooth decay in fluoridated areas progresses more slowly.
