Skip to main content

Oral health: A balancing act


According to the World Health Organisation (WHO), 60-90% of school children are affected by tooth decay in industrialised countries. Topical application of fluorides – for example, fluoride toothpaste or mouthwash – has been recognised as the main reason for the decline in the prevalence of tooth decay worldwide. But while low levels of fluoride reduce tooth decay, at high levels it can damage developing tooth enamel in young children. Getting this balance right is critical.

Research has been undertaken by Vida Zohoori, Professor in Oral Public Health & Nutrition at Teesside University, to ensure health authorities understand the key issues in fluoride exposure before introducing community fluoridation programmes for tooth decay prevention.

The Research

Since 2008, Zohoori’s research has been far-reaching, collaborating with higher education institutions, research centres and food authorities across the globe. It has led to new developments in experimental models, fluoride databases and fluoride monitoring.

Projects have included measuring the fluoride content of more than 750 commercially available foods and drinks. This resulted in the development of a unique fluoride database which was used by the Food Safety Authority of Ireland to carry out a total diet study on fluoride intake in Ireland between 2014 and 2016.

Another project saw Zohoori co-lead a study commissioned by the UK National Fluoridated Milk Advisory Group (NFMG) to assess the fluoride level in milk. Fluoride has traditionally been added to milk as a public health measure for tooth decay control - in the UK, for example, milk fluoridation is used in school-based programmes for children who live in low fluoridated water areas and who are at high risk of tooth decay. This study provided evidence for dental public health consultants and other health professionals to review the amount of fluoride added to school milk. It also indicated that UK schemes should review their current monitoring programmes.

The Impact

Zohoori’s 12-year programme of research has had a global impact. It has reformed WHO policy for the effective surveillance of fluoride exposure and led to changes in water and milk fluoridation schemes in the UK and Ireland.

As a direct result of Zohoori’s research into fluoride exposure, she was invited to a WHO technical working group to change the technical guidelines surrounding fluoride intake and enable countries to plan effective surveillance systems for community prevention programmes. The subsequent guidelines were based extensively on the research and referenced Zohoori directly.

The outcomes of Zohoori’s study with NFMG to assess milk fluoride levels directly informed Blackpool Council’s decision to introduce a fluoridated-milk scheme across 37 local primary schools. Crucially, this scheme has resulted in an improvement in the dental health of children involved and has been referenced as best practice by The British Society of Dental Hygiene and Therapy.

Centre for Public Health

The Centre for Public Health enables, facilitates, identifies and disseminates public health research in co-production across the University and externally with commissioners and communities - on a local, national and international scale.

Visit research centre