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

 

Housing Policy: Auckland Densification As Popular As Ebola, English Says

Finance Minister Bill English said calls by the Reserve Bank Governor for more densification in Auckland’s housing were “about as popular in parts of Auckland as Ebola” would be. More>>

ALSO:

Crown Accounts: NZ Government Deficit Smaller Than Expected In First Half

The New Zealand government's operating deficit was smaller than expected in the first six months of the financial year, as the consumption and corporate tax take rose ahead of forecast in December, having lagged estimates in previous months. More>>

ALSO:

Fruit & Veg Crackdown: Auckland Fruit Fly Find Under Investigation

The Ministry for Primary Industries (MPI) is investigating a find of a single male Queensland fruit fly in a surveillance trap in the Auckland suburb of Grey Lynn... MPI has placed legal controls on the movement of fruit and some vegetables outside of a defined circular area which extends 1.5km from where the fly was trapped in Grey Lynn. More>>

ALSO:

Scoop Business: Westpac NZ Reaches $2.97M Swaps Settlement

Westpac Banking Corp’s New Zealand unit has agreed to pay $2.97 million in a settlement with the Commerce Commission over the way the bank sold interest rate swaps to farmers between 2005 and 2012. More>>

ALSO:

Going Dutch: Fonterra Kicks Off $144M Partnership With Dutch Cheese Maker

Fonterra Co-operative Group, the world’s largest dairy exporter, has commissioned a new dairy ingredients plant in Heerenveen, in the north of the Netherlands, its first wholly-owned and operated ingredients plant in Europe. More>>

ALSO:

Scoop Business: NZ Retail Sales Beat Estimates

New Zealand retail sales rose more than expected in the fourth quarter, led by vehicle-related transactions, food and beverages, adding to evidence that cheap credit and a growing jobs market are encouraging consumers to spend. More>>

ALSO:

Delivery Cuts Go Ahead: 'Government Money Grab' From NZ Post

"It's a money grab by the Government as the shareholder of New Zealand Post" says Postal Workers Union advocate Graeme Clarke about the changes announced by NZ Post. More>>

ALSO:

Get More From Scoop

 
 
Standards New Zealand

Standards New Zealand
 
 
 
 
 
 
 
 
Sci-Tech
Search Scoop  
 
 
Powered by Vodafone
NZ independent news