A further reduction to below 5% or roughly 25 grams (6 teaspoons) per day would provide additional health benefits, the WHO said.

Free sugars refer to monosaccharides (such as glucose, fructose) and disaccharides (such as sucrose or table sugar) added to foods and drinks by the manufacturer, cook or consumer, and sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates.

“We have solid evidence that keeping intake of free sugars to less than 10% of total energy intake reduces the risk of overweight, obesity and tooth decay,” says Dr Francesco Branca, Director of WHO’s Department of Nutrition for Health and Development. “Making policy changes to support this will be key if countries are to live up to their commitments to reduce the burden of noncommunicable diseases.”

The WHO guideline does not refer to the sugars in fresh fruits and vegetables, and sugars naturally present in milk, because there is no reported evidence of adverse effects of consuming these sugars.

Much of the sugars consumed today are “hidden” in processed foods that are not usually seen as sweets. For example, 1 tablespoon of ketchup contains around 4 grams (around 1 teaspoon) of free sugars. A single can of sugar-sweetened soda contains up to 40 grams (around 10 teaspoons) of free sugars.