Researchers at New Zealand's University of Otago have released new findings which show that cutting sugar helps people lose weight.
They are using the findings, published in the British Medical Journal, as a basis to renew calls for sugary drinks to be banned in schools.
Professor Jim Mann and others from Otago's Department of Human Nutrition analysed 71 studies on the effects of sugar on weight.
They found that reducing the amount of sugar adults eat in their normal daily diet causes a weight loss of 800 grams on average over the period covered by the studies, which was from two weeks to more than a year.
Professor Mann says while that seems relatively small, there is evidence of a much larger weight gain or loss from altered sugar intake over time.
He says New Zealand has an obesity epidemic and it is time for the Government to reintroduce a food policy in schools.
The British Medical Journal says the role of sugar in weight gain has been contentious, but the evidence is mounting.