Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 


Fluoridating water does not lower IQ: Otago research

Fluoridating water does not lower IQ: Otago research


New University of Otago research out of the world-renowned Dunedin Multidisciplinary Study does not support claims that fluoridating water adversely affects children’s mental development and adult IQ.

The researchers were testing the contentious claim that exposure to levels of fluoride used in community water fluoridation is toxic to the developing brain and can cause IQ deficits. Their findings are newly published in the highly respected American Journal of Public Health.

The Dunedin Study has followed nearly all aspects of the health and development of around 1000 people born in Dunedin in 1972-1973 up to age 38.

Lead author Dr Jonathan Broadbent says the new research focused on Study members’ fluoride exposure during the first five years of their lives, as this is a critical period in brain development, after which IQ is known to be relatively stable.

Dr Broadbent and colleagues compared IQs of Study members who grew up in Dunedin suburbs with and without fluoridated water. Use of fluoride toothpaste and tablets was also taken into account.

They examined average IQ scores between the ages of 7-13 years and at age 38, as well as subtest scores for verbal comprehension, perceptual reasoning, working memory and processing speed. Data on IQ were available for 992 and 942 study members in childhood and adulthood, respectively.

Dr Broadbent says the team controlled for childhood factors associated with IQ variation, such as socio-economic status of parents, birth weight and breastfeeding, and secondary and tertiary educational achievement, which is associated with adult IQ.

“Our analysis showed no significant differences in IQ by fluoride exposure, even before controlling for the other factors that might influence scores. In line with other studies, we found breastfeeding was associated with higher child IQ, and this was regardless of whether children grew up in fluoridated or non-fluoridated areas.”

Dr Broadbent says that studies that fluoridation opponents say show that fluoride in water can cause IQ deficits, and which they heavily relied on in city council submissions and hearings, have been reviewed and found to have used poor research methodology and have a high risk of bias.

“In comparison, the Dunedin Multidisciplinary Study is world-renowned for the quality of its data and rigour of its analysis,” he says.

“Our findings will hopefully help to put another nail in the coffin of the complete canard that fluoridating water is somehow harmful to children’s development. In reality, the total opposite is true, as it helps reduce the tooth decay blighting the childhood of far too many New Zealanders.”

This work was supported by the New Zealand Ministry of Education, the New Zealand Department of Health, the New Zealand National Children’s Health Research Foundation, US National Institute of Dental and Craniofacial Research Grant R01 DE-015260-01A1, UK Medical Research Council Grant MR/K00381X/1, US National Institute on Aging Grant AG032282, and a programme grant from the Health Research Council (HRC) of New Zealand. The Dunedin Multidisciplinary Health and Development Research Unit is supported by the HRC.

Ends

© Scoop Media

 
 
 
 
 
Business Headlines | Sci-Tech Headlines

 

Auckland Port Study: Port To Ship Out – No Departure Date

Interest groups in Auckland and its waterfront chose a group of representatives to determine the future of the port. Their consensus is that the Port is going to have to move but not before a credible location is confirmed... More>>

ALSO:

Tax: GST Threshold For Online Purchases Won't Lower Before 2018

The government wants to lower the threshold on online purchases which qualify for GST from mid-2018, but says more work is needed and there will be no change without public consultation. More>>

ALSO:

North Canterbury: Government Extends Drought Classification

The government has extended a drought classification for the eastern South Island until the end of the year, meaning the area will have officially been in drought for almost two years, the longest period for such a category. More>>

ALSO:

Negotiations Fail: Christchurch Convention Centre Build To Proceed Without PCNZ

After protracted negotiations, the government has ditched the construction consortium it picked to build Christchurch's replacement convention centre, which it now anticipates delivering at least two years behind the original schedule. More>>

ALSO:

Other Centres' Convention Centres:

Ruataniwha: Greenpeace Launches Legal Challenge Against $1b Dam Plan

Greenpeace NZ is launching a legal challenge against a controversial plan to build a dam that’s set to cost close to $1 billion and will pollute a region’s rivers. More>>

ALSO:

Get More From Scoop

 
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news