Martin Glenn, president of PepsiCo UK, which owns the Walkers Snacks business, will be among the marketers to give evidence to the Health Select Committee's Inquiry into Obesity on November 27.
A session two weeks earlier will hear from Cilla Snowball, chief executive of Walkers' advertising agency, Abbott Mead Vickers BBDO, Advertising Association director-general Andrew Brown and Bruce Haines, group chief executive of Leo Burnett, which handles the McDonald's account.
Marketing can also reveal that McDonald's, under fire from pressure groups for marketing tactics which include giving away toys with children's meals, has finally bowed to industry pressure and become a member of the MediaSmart kids' education programme. Other members of the scheme include Heinz and Masterfoods.
The Health Select Committee evidence sessions are likely to subject witnesses from the industry to intense pressure to defend long-established marketing practices.
Earlier this week, Labour MP Debra Shipley reintroduced her Bill to ban food and drink ads from children's TV into the House of Commons. Children's minister Margaret Hodge has signalled that she is looking into such a ban.
Supporters of a clampdown on ads aimed at children have seized on a recent Food Standards Agency report showing a link between advertising and food consumption among children. It will publish policy guidelines in the new year.
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