Interview with:
Professor Aubrey Sheiham
Emeritus Professor of Dental Public Health
Department of Epidemiology & Public Health,
University College London, WC1E 6BT. UK.

Medical Research: What are the main findings of the study?

Prof Sheiham: There is a robust log-linear relationship of caries to sugar intakes from zero to 10% of sugars as a proportion of total energy intake. Furthermore our analyses showed that sugar intakes of 10%E sugars intake that is currently recommended as an upper limit for free sugars by the WHO and the Scientific Advisory Committee on Nutrition in England would induce a very costly burden of caries in most populations. Second, we found that free sugars* in the diet should make up no more than 3% of total energy intake. Above that level they cause a significant level of tooth decay across the lifecourse of most people in the developed world. Third, we were able to show that despite widescale fluoride use from both toothpastes and drinking water the mean numbers of decayed, missing and filled teeth (DMFT) and decayed and filled surfaces (DFS) for adults increased with sugar use despite the presence of fluoride.

*Free sugars are defined by the World Health Organisation Nutrition Guidance Adivisory Group as follows: “Free sugars include monosaccharides and disaccharides added to foods by the manufacturer, cook or consumer, and sugars naturally present in honey, syrups, fruit juices and fruit concentrates.”

Medical Research: What was most surprising about the results?

Prof Sheiham: My previous research published in the Lancet in 1983 that the dose-response relationship between sugars and caries was only sigmoid, was shown to be wrong. We found that there is no evident threshold for sugars but a log-linear increase in caries rates.

Medical Research: What should clinicians and patients take away from your report?

Prof Sheiham: Current approaches to controlling dental caries are failing to prevent high levels of caries in adults in all countries and this relates to the current high level of sugar intake across the globe. Thus, for multiple reasons, including obesity and diabetes prevention, we need to adopt a new and radical policy of progressive sugar reduction.

The progressive accumulation of dental caries, despite widespread use of fluoride, shows that sugars intakes should be <3%E to minimize the disability and cost of dental caries in a population.

Medical Research: What recommendations do you have for future research as a result of this study?

Prof Sheiham: Studies should examine the barriers to implementation of policies to reduce sugars consumption and the public acceptability of measures, such as reducing availability of free sugars in school meals and in vending machines in publicly funded institutions.


A reappraisal of the quantitative relationship between sugar intake and dental caries: the need for new criteria for developing goals for sugar intake.
Sheiham Aubrey, James W Philip T. BMC Public Health. 2014, 14:863
DOI: 10.1186/1471-2458-14-863