Cadbury Trebor Bassett and Mars, whose ranges include Starburst, Skittles and M&Ms, promised to speed up plans to ditch seven E-numbers identified in research last week by Southampton University.
The study, commissioned by the Food Standards Agency (FSA), found the clearest link yet between the six artificial colors and one preservative commonly used in processed foods and products high in sugar, and a child's behavior.
Children who have shown no previous hyperactive behavior became less focused and more impulsive after being fed the additives in question. The FSA said the findings were not enough to justify banning the additives, as they "do not constitute an immediate threat to health." However, it was accused by some experts and campaign groups of failing to do enough.
Mars, which currently uses one or more of the seven highlighted additives in Skittles, Starburst and M&Ms, has promised to remove all artificial colors from Starburst by the end of this year.
Those highlighted in the study will be removed from Skittles in the same period. All but two of the named additives will also be eradicated from peanut and Choco M&Ms, the firm said.
Cadbury Trebor Bassett said in light of the findings it had decided to speed up a program to axe the additives currently found in Maynards Wine Gums, Bassett Murray Mints, Barratt Flumps and varieties of Trident chewing gum.
A spokesman said, "Cadbury Trebor Bassett have listened to consumers and are committed to replacing all artificial colors in our sweets by the end of 2008. All sweet brands will now switch before the end of next year."
The confectioner Haribo has already announced that it will replace the artificial ingredients in its products with natural alternatives by the end of the year.
Tesco, Sainsbury's, Asda, Marks & Spencer and the Co-op made similar promises for their own-label products.
The artificial colors tested in the study were tartrazine (E102), ponceau 4R (E124), sunset yellow (E110), carmoisine (E122), quinoline yellow (E104) and allura red AC (E129). Also under suspicion is the preservative sodium benzoate (E211).
From the September 24, 2007, Prepared Foods e-Flash