Diet Pepsi to ditch the aspartame

Bruce Horovitz | USA TODAY

Diet Pepsi is finally giving aspartame the heave-ho.

Spurred by falling sales and consumer safety concerns, PepsiCo North America Beverages announced on Friday that an aspartame-free Diet Pepsi — sweetened with sucralose and ace-K — will hit shelves some time in August. Pepsi executives say the new Diet Pepsi sweetener formulation tastes the same as the old one.

Large lettering on the new Diet Pepsi cans and packaging will shout: "Now Aspartame Free."

For many consumers — who fear aspartame's side effects — and for PepsiCo, which has seen Diet Pepsi sales tumble over the past several years, the change can't come soon enough. Last year, Diet Pepsi volume was down -5.2% and Diet Coke volume was down -6.6% in the U.S., reports Beverage Digest, the industry trade publication.

PepsiCo has spent years trying to develop a new Diet Pepsi sweetener that would placate consumer concerns but still appeal to consumer tastes. The move would seem to put pressure on arch-rival Coke, which also has seen Diet Coke sales slump, to make a similar move.

PepsiCo shares were down slightly in mid-day trading.

"To Diet Pepsi consumers, removing aspartame is their No. 1 one concern," says Seth Kaufman, senior vice president of Pepsi and flavors, in a phone interview. "We're listening to consumers. It's what they want."

Pepsi could no longer afford to sit back and simply watch its Diet Pepsi sales keep falling.

"This is an aggressive move by Pepsi. It has the potential of helping Pepsi recruit new and lapsed users for Diet Pepsi," said John Sicher, editor and publisher of Beverage Digest. But the move also has some risk, he says. It could confuse some loyal Diet Pepsi users, though it is the sweetener blend that's changing, not the flavor formula."

The change applies to all versions of Diet Pepsi, such as Caffeine Free Diet Pepsi and Wild Cherry Diet Pepsi sold in the U.S. Diet Pepsi was introduced in 1964, with saccharin as its sweetener. It was reformulated with aspartame in 1983, and then switched to a blend of aspartame and ace-K in 2013.

While critics of aspartame say they are pleased with the move, one critic says that the new sweetener still has a problem: ace-K.

"Diet Pepsi will still contain acesulfame-potassium (ace-K). Consumers should avoid that sweetener as well," warns Michael Jacobson, director of Center for Science in the Public Interest, an advocacy group. "It is poorly tested, but the tests done by the manufacturer in the 1970s suggest that ace-K, too, might pose a cancer risk."

Pepsi officials strongly deny that. "Decades of studies have shown that the sweeteners we use are safe," says spokeswoman Elisa Baker, in an -mail.

For that matter, Kaufman insists it is changing consumer preferences — not a safety issue — that led PepsiCo to make the change: "Decades of studies have shown that aspartame is safe. This is not about safety."

But Jacobson says scientific studies have shown a link between aspartame and cancer. "Three top-quality studies have found that aspartame causes cancer in animals, so the less that people consume the better," he says.

One medical expert, however, disagrees. "Aspartame's safety in the quantities the general public consumes has been established as safe many, many times over," says Rebecca Blake, director of clinical nutrition at New York's Mount Sinai Beth Israel. "The research does not yet support a greater level of safety among the 'more natural' sweeteners."

For the moment, PepsiCo says it has no plans to replace aspartame in other diet beverages, including Diet Mountain Dew, which also has seen a sales decline.

Meanwhile, officials at Coca-Cola appeared Friday to be unmoved by Pepsi's action. "There are currently no plans to change the sweetener for Diet Coke, America's favorite no-calorie soft drink. All of the beverages we offer and ingredients we use are safe," the company said, in an e-mailed statement.

Jacobson, the consumer advocate, says the best thing is probably to avoid most colas altogether. "My best advice is to refresh yourself with water, seltzer water, or flavored waters."