A report commissioned by the World Heatlh Organisation (WHO) and the Food and Agriculture Organization last year suggested that free sugars should be restricted to less than 10 per cent total energy but a food industry lobby said that evidence to support this recommendation was insufficient.
In today's article (vol 363, p1068), Jim Mann from the University of Otago, New Zealand argues that "although none of the individual studies might be definitive, when considered in aggregate they provide considerable evidence to suggest that sucrose and other free sugars contribute to the global epidemic of obesity".
He also claims that two of the studies cited by US lobbyists as evidence for sugar intake, one from the US Institute of Medicine, the other from the FAO in 1998, have been misrepresented. Mann is calling for both organizations to modify or clarify possible ambiguities in their reports to help the WHO strategy on diet, which has been informed by the expert report released last year, go ahead.
Intensive lobbying from the US food industry threatens the adoption by the World Health Assembly of this strategy, in which reductions in fat and salt and increased physical activity are also recommended.
But Mann cites evidence to justify limiting sugar intake. This includes studies showing that children drinking a lot of sugary drinks are more likely to put on weight while sucrose restriction results in weight loss in free-living individuals. There have also been several studies showing that increasing the ratio of simple to complex carbohydrates is associated with weight gain and increased triglyceride concentrations.
"Without doubt, sugar is still of huge importance in the global economy and it is clearly important to consider whether sufficient evidence indeed exists to recommend restriction of intake. But reduction of the intake of sugars can make a useful contribution -along with other measures - to lessening of the risk of obesity and its clinical outcomes," he writes.
He adds that South Africa has joined the list of countries that include advice about sugar intake in dietary guidelines. "Nations that have not yet included recommendations on sugar intake might well consider an approach similar to that taken by the South Africans: 'Consume food and drinks containing sugar sparingly and not between meals'."