Just so everyone is clear: this review found that there is little evidence that water fluoridation has any benefits. It does not dispute that fluoride in toothpaste reduces tooth decay.
> Studies that attest to the effectiveness of fluoridation were generally done before the widespread usage of fluoride-containing dental products like rinses and toothpastes in the 1970s and later, according to the recent Cochrane study. So while it may have once made sense to add fluoride to water, it no longer appears to be necessary or useful, Thiessen says.
> It has also become clear in the last 15 years that fluoride primarily acts topically, according to the CDC. It reacts with the surface of the tooth enamel, making it more resistant to acids excreted by bacteria. Thus, there's no good reason to swallow fluoride and subject every tissue of your body to it, Thiessen says.
> Another 2009 review by the Cochrane group clearly shows that fluoride toothpaste prevents cavities.
Unfortunately, it's not accurate to say there is no evidence. There is evidence, it's just old evidence. For some reason, Newsweek decided to focus on the fact that there is no evidence that fluoridation is helpful for adults, and that the evidence for children is almost all from before 1975. That is important since behaviors may have changed post-1975.
The "Plain language summary" from the authors - their words, so this is the authors of the study synthesizing their conclusions for a lay audience - is clear:
Data suggest that the introduction of water fluoridation resulted in a 35% reduction in decayed, missing or filled baby teeth and a 26% reduction in decayed, missing or filled permanent teeth. It also increased the percentage of children with no decay by 15%. Although these results indicate that water fluoridation is effective at reducing levels of tooth decay in children's baby and permanent teeth, the applicability of the results to current lifestyles is unclear because the majority of the studies were conducted before fluoride toothpastes and the other preventative meaures were widely used in many communities around the world.
There was insufficient information available to find out whether the introduction of a water fluoridation programme changed existing differences in tooth decay across socioeconomic groups.
There was insufficient information available to understand the effect of stopping water fluoridation programmes on tooth decay.
No studies met the review’s inclusion criteria that investigated the effectiveness of water fluoridation for preventing tooth decay in adults, rather than children.
The theory I've encountered is that fluoridation previously had an impact on cavity-prevention before people were actually brushing their teeth with fluoridated toothpaste. Now that toothbrushing is much more common, the impact has waned.
Late edit;
Here's a look at toothbrushing frequency in Europe by country from 1994 - 2010:
Just imagine how much improvement you'd see from if the chart started in the 1940's and 1950's when many cities began fluoridating their water supplies. Not to mention that many early toothpastes were often ineffective at preventing cavities by primarily relying on baking soda and peroxide.
remember that non controlled measurements are worthless.
same time they started water fluoridation the population also started to pay attention to brushing their teeth. or do you think the govt took the initiative at any point in history?
Yup, fluoride in toothpaste is indeed pretty efficient.
And apparently more of it the better. There are even benefits of using stronger fluoride concentrations than just regular toothpaste's 1400-1450 ppm. Humble old fluoride seems to work better than fancy calcium sodium phosphosilicate (also known as NovaMin):
"The purpose of this in vitro study was to evaluate the effect of toothpastes containing sodium fluoride in different concentrations or a calcium sodium phosphosilicate system on pre-softened dentin demineralization and remineralization.
Under these experimental conditions, the high fluoride toothpastes promoted remineralization and inhibited demineralization more effectively, than the 1450 ppm F, the non-fluoridated (control) and the calcium sodium phosphosilicate toothpastes."
There are special high-fluoride gels used by dentists / dental hygienists / can be bought in pharmacies; they can help a lot if you have sensitive teeth.
> this review found that there is little evidence that water fluoridation has any benefits. It does not dispute that fluoride in toothpaste reduces tooth decay
This agrees well with a personal observation of mine. A majority of those I know who grew up in the 1970's or earlier have a mouth full of fillings. Yet almost everyone I know who grew up in the 1990's or later have few or zero fillings.
I've asked several different dentists about this observation. The dentists agree with my observation but they reflexively attribute it to fluoridation of water. But fluoridation began in my area in the 1960's (I checked). The dentists are wrong about fluoridation explaining the difference between '70s kids and '90s kids.
If we were to assume that toothpaste commonly began to contain fluoride after the mid or late 1970's, that would be consistent with a decline in cavities.
> If we were to assume that toothpaste commonly began to contain fluoride after the mid or late 1970's
Not sure, but that sounds wrong according to wikipedia:
> Fluoride was first added to toothpastes in the 1890s. "Tanagra", containing calcium fluoride as the active ingredient, was sold by Karl F. Toellner Company, of Bremen, Germany, based upon the early work of chemist Albert Deninger.[31] An analogous invention by Roy Cross, of Kansas City, Mo., was initially criticized by the American Dental Association (ADA) in 1937. Fluoride toothpastes developed in the 1950s received the ADA's approval. To develop the first ADA-approved fluoride toothpaste, Procter & Gamble started a research program in the early 1940s. In 1950, Procter & Gamble developed a joint research project team headed by Dr. Joseph Muhler at Indiana University to study new toothpaste with fluoride. In 1955, Procter & Gamble's Crest launched its first clinically proven fluoride-containing toothpaste. On August 1, 1960, the ADA reported that "Crest has been shown to be an effective anticavity (decay preventative) dentifrice that can be of significant value when used in a conscientiously applied program of oral hygiene and regular professional care."
> Studies that attest to the effectiveness of fluoridation were generally done before the widespread usage of fluoride-containing dental products like rinses and toothpastes in the 1970s and later, according to the recent Cochrane study. So while it may have once made sense to add fluoride to water, it no longer appears to be necessary or useful, Thiessen says.
> It has also become clear in the last 15 years that fluoride primarily acts topically, according to the CDC. It reacts with the surface of the tooth enamel, making it more resistant to acids excreted by bacteria. Thus, there's no good reason to swallow fluoride and subject every tissue of your body to it, Thiessen says.
> Another 2009 review by the Cochrane group clearly shows that fluoride toothpaste prevents cavities.