Fluoride in tap water, drinks and food poses no risk to the health of adults and children, according to a major Irish study.

Fluoride is added to public water supplies to combat tooth decay.

High levels of fluoride can be found naturally in black tea - which can constitute up to 76% of an adult's total fluoride exposure - with smaller amounts also present in a range of different food types.

The Food Safety Authority (FSAI) has now carried out the most comprehensive study on the mineral ever undertaken in Ireland.

The research took the form of a total diet study - which estimates the exposure of a population to contaminants or other food chemicals - carried out between 2014 and 2016.

Fluoride exposure in children was found to be much lower than in adults due to adults' higher consumption of black tea.

Excessive fluoride intake can effect bone and teeth density, but the study results found that combining fluoride from toothpaste and food and drink does not amount to this.

However, the researchers do warn that 'misuse of toothpaste' by swallowing it can result in higher intakes of fluoride in a small proportion of young children.

The report concludes: "Based on the results of this study, the FSAI Scientific Committee concluded that there is currently no scientific basis for concerns about the safety of children and adults in Ireland from exposure to fluoride from foods and beverages."

Dr Pamela Byrne, CEO of the FSAI, explained: "This report serves to provide independent and impartial information on the exposure to fluoride through the Irish diet. It is an important piece of research which also takes into account naturally occurring levels of fluoride in food and beverages we consume in our diets in Ireland.

"This study reaffirms the FSAI’s and its Scientific Committee’s view that exposure to fluoride from the diet for all population groups in Ireland is not of concern."