Scientific Reviews: Assessing the Weight of
the Evidence
Reviews of scientific literature are an important resource to judge
the safety of community water fluoridation. Scientific reviews are
helpful because they—
- Consider evidence from published studies on a subject.
- Use carefully-designed methods to critically examine scientific
evidence.
- Use national and international panels of experts in various health
and scientific disciplines. This includes experts that may come from
fields outside of oral health; such as, medicine, biophysics, chemistry,
toxicological pathology, and epidemiology.
- Judge the quality of individual studies and summarize the strength
of the entire body of evidence.
- Identify and summarize research gaps and make recommendations for
further research.
Scientific and pubic health organizations have conducted scientific
reviews about fluoridation during the past two decades. These reviews
provide compelling evidence that community water fluoridation is a safe and
effective method for reducing tooth decay across all ages.
United States Public Health Service Review of Fluoride: Benefits and
Risks, 1991
This report provides a comprehensive review and evaluation of the public health benefits and
risks of fluoride from drinking water and other sources.
Institute of Medicine Dietary Reference Guidelines, 1997*
These guidelines describe
the dietary reference intakes for specific nutrients known to be
beneficial to health including fluoride.
National Research Council
The National Research Council (NRC) released its current report, Fluoride in Drinking Water: A
Scientific Review of EPA’s Standard, on March 22,
2006. The NRC's previous report, entitled
Health Effects of Ingested Fluoride*,
was issued in 1993. It examined the
possible toxic effects of ingested fluoride and concluded—
- Fluoride at recommended concentrations is not likely to produce a
number of unwanted health effects that had been claimed by opponents
of water fluoridation.
- The maximum contaminant level (MCL) set by the Environmental
Protection Agency (EPA) at 4 mg/L was an appropriate interim standard,
even though fluoride at this level might cause moderate or even
severe dental fluorosis in a small percentage of the population.
Australian Government
Australia's National Health and Medical Research Council (NHMRC)
conducted a systematic review published in 2007, that considered recent
evidence relating to the efficacy and safety of fluoride interventions, with
an emphasis on widespread public health initiatives. The report,
A
Systematic Review of the Efficacy and Safety of Fluoridation, primarily
addressed the caries-reducing benefits and associated health risks of
providing fluoride systemically. The council found that—
- Community water fluoridation is beneficial for reducing dental
caries (tooth decay).
- Water fluoridation at optimal levels does not affect the risk of
bone fractures.
- There is no clear association between water fluoridation and overall
cancer incidence or mortality.
- The reviewed studies do not suggest an increased risk of adverse
health effects at optimal fluoridation levels.
NHMRC is Australia's main agency for supporting health and medical
research; developing health advice for the Australian community, health
professionals, and governments; and providing advice on ethical behavior in
health care and conduct for health and medical research.
University of York
A systematic review of public water fluoridation* was released in 2000
by the National Health Service (NHS) Centre for Reviews and Dissemination, University of York,
United Kingdom.
This looked at the evidence of positive and negative effects for community water fluoridation. They identified five objectives and
evaluated the studies relating to each objective. Based on the best
available research they found that—
- Community water fluoridation reduces tooth decay.
- Fluoridation is still effective even with the use of many other
sources of fluoride.
- There is no clear association between fluoridation and bone
fractures or cancer.
- There appears to be no difference between benefits from natural
and artificial fluoridation.
- There is an association between the water fluoride concentration
and the occurrence of enamel fluorosis.
- No clear evidence of other potential negative health effects were
found.
Additional systematic reviews on the benefits of water fluoridation
may be viewed on the Benefits page.
* Links to non-Federal organizations are
provided solely as a service to our users. Links do not constitute an
endorsement of any organization by CDC or the Federal Government, and none
should be inferred. The CDC is not responsible for the content of the individual
organization Web pages found at this link.
Date last reviewed:
December 9, 2008
Date last updated: December 10, 2008
Content source:
Division of Oral Health, National Center for Chronic Disease Prevention and
Health Promotion |