A review by a panel of leading scientists says fluoridated drinking water in New Zealand creates no health risks and provides protection against tooth decay.
The review was commissioned by the Prime Minister's chief science adviser, Sir Peter Gluckman, at the request of Auckland City on behalf of several local councils.
It said claims that fluoride had adverse health affects were not supported by scientific evidence.
About half of all councils put fluoride in their water, and the review made clear that they could be confident it was safe.