Sugars in the diet should make up no more than 3 per cent of total energy intake to reduce the significant financial and social burdens of tooth decay, according to a new research.
The study from University College London (UCL) and the London School of Hygiene & Tropical Medicine, analysed the effect of sugars on dental caries, also known as tooth decay.
They show that sugars are the only cause of tooth decay in children and adults.
Tooth decay is the most common non-communicable disease in the world, affecting 60-90 per cent of school-age children and the vast majority of adults, researchers said.
The treatment of dental diseases costs 5-10 per cent of total health expenditure in industrialised countries, they said.
Researchers used public health records from countries across the world to compare dental health and diet over time across large populations of adults and children.
They found that the incidence of tooth decay was much higher in adults than children, and increased dramatically with any sugar consumption above zero per cent of energy.
Even in children, an increase from near-zero sugar to 5 per cent of energy doubles the prevalence of decay and continues to rise as sugar intake increases.
Current guidelines from the World Health Organisation set a maximum of 10 per cent of total energy intake from free sugars, with 5 per cent as a 'target'.
This equates to around 50g of free sugars per day as the maximum, with 25g as the target. The latest research suggests that 5 per cent should be the absolute maximum, with a target of less than 3 per cent.
"Tooth decay is a serious problem worldwide and reducing sugars intake makes a huge difference," said study author Aubrey Sheiham, Emeritus Professor of Dental Public Health at UCL Epidemiology & Public Health.
The study was published in the journal BMC Public Health.