Health campaigners want a ban on price promotions for confectionery and the sugar tax extended to sweets and chocolates.
Action on Sugar assessed 95 different products, with some containing 29 teaspoons of sugar – almost four times the recommended daily allowance for an adult.
The group said that discounting “sharing bags” is encouraging excessive sugar consumption. Research in 2014 published by the Grocer showed that 22% of people admit to eating the super-sized bags alone, in one go.
Consumption of confectionery is the second highest contributor to sugar intake in children, after soft drinks.
Action on Sugar urged the government to introduce a ban on promotions for foods high in fat, salt and sugar.
Research by consumer group Which? in 2016 found that 53% of the products on promotion in supermarkets were “unhealthy”.