New guidelines from the World Health Organization say the world is eating too much sugar.

It's released guidelines saying people should slash their sugar intake to just 5 to 10% of their overall calories.

Sky's Adele Robinson says the WHO year-long study has focused on the added sugars in processed food and those in honey, syrups and fruit juices.

"The advice follows studies of the impact of sugar on obesity and dental cavaties. But some experts believe the 5% target isn't realistic."

One of the reasons is that without comprehensive labelling, it's difficult to tell which processed foods are hiding excess sugar.