The actress, 32, has been named Ambassador Against Hunger for the United Nations' World Food Program, and she'll work as an advocate for school feeding programs in developing countries.
Barrymore spoke out about her new role on CNN with Wolf Blitzer. (See the CNN.com video here.)
"I was reading an article in the New York Times about school feeding programs, and I work in documentary now," Barrymore said. "I went and called the U.N. and said ... if there's an opportunity where I could go to Africa and bring my crew and start filming, it would be wonderful.
"These children, their incentive to go to school is to get one cup of food a day," she added. "What that cup enables them is to have the concentration to learn.
Guillaume Bonn / WFP
Barrymore, named PEOPLE's World's Most Beautiful in 2007, recently returned from a second trip to Kenya to visit WFP-supported school feeding projects. "Feeding a child at school is such a simple thing – but it works miracles," she said in a statement. "I've seen it with my own eyes."
For more on Drew and PEOPLE's other Most Beautiful of '07, click here.