Following the publication of the Food and Drink Federation's 'Manifesto for Food and Health' on Monday, Cadbury said it was pulling its king-size bars, which include Crunchie and Boost. Its 'king-size' Dairy Milk bar is being reduced in size by 10g to 75g.
Walkers has said it has no plans to change its range of pack sizes. The refusal counters statements made by PepsiCo UK president Martin Glenn at a Marketing Society event earlier this year, when he welcomed moves by McDonald's to axe its Supersize meals.
Rob Morgan, marketing director of Golden Wonder, described the actions by Cadbury and Masterfoods - ditching its king-size Mars and Snickers bars - as 'symbolic gestures'.
Walkers has pledged to slash saturated fat content across its crisp ranges, moving to a level of 50% by 2006.
The company is backing the initiative with a £3m TV ad campaign, breaking next month, which will promote a 'Walk-o-Meters' giveaway in a tie-up with The Sun.