Almost half of all carbonated drinks on UK supermarket shelves contain the controversial sweetener aspartame, according to The Grocer analysis of Assosia data.
By comparison, sugar was use in around a third of all fizzy drinks (32%).
The percentage of fizzy drinks to contain the sweetener has jumped up from 45% this time last year. This was down mainly to more sugar-free drinks hitting shelves rather than reformulations.
Just over 10% of drinks contain both aspartame and sugar.
Despite the recent move by WHO, the organisation still deemed aspartame to safe for consumption at current permitted use levels, 40mg per kg of bodyweight. For an adult weighing 70kg, that equates to between nine and 14 cans of sugar-free cola a day.
Aspartame is primarily found in branded lines while there only few own-label carbonates use the sweetener. Major branded lines to use aspartame include Coca-Cola brands Zero Sugar, Diet Coke, Dr Pepper, Sprite and Sprite No Sugar, Schweppes Lemonade and Diet Lemonade, Fanta Fruit, Fanta Lemon, and Fanta Orange Zero. Pepsi brands Pepsi Max No Sugar and 7up Zero also contained aspartame.
The own-label drinks with aspartame include Waitrose Cloudy Lemonade No Added Sugar, Waitrose Ginger Beer No Added Sugar and Morrisons Cola Zero Sugar. Most own label fizzy drinks with diet and no sugar versions tending to use sucralose and acesulfame K.
Both Morrisons and Waitrose said they were currently reviewing the ingredients for own-label soft drinks.
“As a responsible retailer, we’re committed to helping our customers reduce the amount of sugar in their diets,” said a Waitrose spokeswoman. “Sweeteners offer one way to do this, but we are also gradually reducing sugar in products as well as offering products sweetened only with naturally occurring sugars.
“We label all sweeteners used in our products in the ingredients list, including the very small number of products which contain low levels of aspartame.
“While the World Health Organization has provided reassurance that aspartame is safe to use, we’re looking into options to use alternative sweeteners for these products.”