Children can consume 92.5 grammes of sugar and more than 1,300 calories from just three common snacks during a day, some of which are sold in school canteens, health campaigners have warned.

Action on Sugar found that a packaged cake, a chocolate bar and two biscuits consumed over the course of a day could add up to three times the recommended daily sugar limit for children aged 11 and over.

The study also found that 61% of cakes, 63% of chocolate confectionery and 44% of biscuits surveyed equalled or exceeded one third – or 10g – of the daily sugar limit for children.

The charity is urging the government to extend the successful Soft Drinks Industry Levy to include such high-sugar foods.

It also warned that the current School Food Standards could be driving children to exceed their daily sugar limits by allowing cakes and biscuits to be sold in canteens at lunchtime.

It is calling for a ban on those items that could contribute to children exceeding their maximum daily limit of sugar at school, alongside the creation of healthier food environments around schools to help young people to eat better.

In its survey of 185 cakes, 92 chocolate confectionery products and 360 biscuits, the charity found the worst combination in terms of calories included Sainsbury’s Taste the Difference Free From Gluten Blueberry Muffins containing 361 calories and 28.5g of sugar, or seven teaspoons, combined with the Ritter Sport White Whole Hazelnuts (583 calories and 44g of sugar, or 11 teaspoons) and two Aldi Specially Selected Orkney Caramel Shortbreads containing 382 calories and 20g of sugar.

Action on Sugar said the figures also emphasised the “failure” of the Government’s voluntary Sugar Reduction Programme which aimed to cut sugar by 20% across key product categories by 2020, finding it achieved minimal reductions in categories such as cakes (down 3.2%), biscuits (down 3.1%) and chocolate confectionery (down 0.9%).

In comparison, the Government’s mandatory Soft Drinks Industry Levy achieved a 34.3% reduction in sugar content.

Dr Kawther Hashem, head of research at Action on Sugar, said: “The truth is, sugary foods are almost inescapable for most children – they’re readily available in schools and often the easiest choice on the way home.

“We’re simply not doing enough to support children in keeping their sugar intake within recommended guidelines. We have a duty to every child to make school a sanctuary from unnecessary sugar, so they can grow up healthier, stronger and free from the risks of diet-related disease.”

Action on Sugar chairman Graham MacGregor said: “Whilst the previous Government’s Sugar Reduction Programme failed due to a lack of meaningful enforcement, the Soft Drinks Industry Levy proved that targeted, well-orchestrated action works.

“This new government now has a unique opportunity to prioritise the health of the nation by implementing a clear, straightforward approach across the food and drink industry which could save the NHS billions and save many thousands of lives.”