The commission says tests on 25 well-known orange drinks, including Kia-Ora and Robisons, found sweeteners in both low calorie and regular brands.

Consumer affairs correspondent Nicola Carslaw reports

It believes price may be the reason. Artificial sweeteners cost a fraction of the price of sugar, despite safety concerns about them.

Aspartame, for example, costs two pence per litre of drink, compared with six pence per litre for sugar.

A government survey in 1992 found that children were consuming large amounts of saccharin and that a significant number of children under five were exceeding recommended safety levels.

The Food Commission says the survey was conducted before a change in legislation allowing companies to put sweeteners in regular drinks.

It believes that if the survey was conducted now it would show children were consuming much more sweetener than in 1992.

Dr Tim Lobstein, the Food Commission's co-director, said: "There are continuing safety concerns about these additives and we want their widespread use to be re-assessed."

Health scares

There have been several scares concerning the most popular sweeteners. Studies on aspartame or Nutrasweet have found the sweeteners may cause headaches and migraines.

Saccharin has been linked to bladder cancer in rats and other forms of cancer in monkeys.

However, manufacturers say people have to consume large amounts of sweeteners to become ill.

The UK government introduced new regulations on sweeteners in 1997 due to public concerns about them.

These say that manufacturers must state clearly next to the name of the product the phrase "with sweeteners".