Ruben Sprich—Reuters
By Bill Saporito
October 2, 2014

Joining Coca-Cola and Dr. Pepper Snapple Group via the Clinton Global Initiative (CGI), the PepsiCo CEO has promised to reduce by 20% the number of calories Americans consume in soft drinks by 2025–despite skepticism from Wall Street.

CLAIMS TO FAME

She’s helped execute a major overhaul of Pepsi by buying Tropicana, merging with Quaker to get Gatorade and putting PepsiCo on an innovation diet. She has also championed Pepsi’s Performance With Purpose platform, which aims to make the company more socially responsible.

CURRENT CHALLENGES

Soda sales in the U.S. have been slipping for years, prompting investors like Nelson Peltz to call for splitting the company in two: Pepsi, the beverage outfit, and Frito-Lay, the snack-food unit. Meanwhile, Wall Street whines about Nooyi’s healthier product initiatives, since junk food tends to be very profitable.

BIGGEST CHAMPION

Former President Bill Clinton, whose CGI has worked with the soda industry to make lower-calorie drinks available for a test group of U.S. middle and high schools.

BIGGEST CRITIC

Marion Nestle, a professor of nutrition at New York University, who has dismissed Nooyi’s initiative as a PR ploy. If soda sellers really want to help Americans drink fewer sugary products, she argues, they should stop fighting soda-tax initiatives in cities like San Francisco.

CAN SHE DO IT?

The just-announced Pepsi True, sweetened by a sugar and stevia combo, contains 60 calories in each 7.5-oz. can–30% fewer than regular Pepsi–and will be available by the 24-can case in mid-October. Critics may find True easier to swallow; will consumers?

–BILL SAPORITO

Contact us at editors@time.com.

This appears in the October 13, 2014 issue of TIME.

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