FYI: Can Japan’s Latest Soft Drink Really Help You Lose Weight?

Pepsi Special claims to block the body’s ability to absorb fat. How does that work?

Soft drinks and weight loss don’t usually go hand-in-hand. But Pepsi aims to change that with a new drink the company has just launched in Japan, called Pepsi Special. The soft drink has an added ingredient, dextrin, that the distributor, Suntory, says reduces your body’s ability to absorb fat. So does that mean you can finally enjoy your soda with a slice of cheesy pizza, hold the guilt?

A 2006 Japanese study indicated that rats fed dextrin and fat at the same time absorbed less fat than rats that weren’t fed dextrin. The Japanese government certifies Pepsi Special and another dextrin-containing soda, Kirin Mets Cola, as “foods for specific health use.” But what works for rats may not work for people, and anyway, “There’s no study that shows that putting dextrin in a beverage is going to cause weight loss. After all, soda has a fair amount of calories,” says Joan Salge Blake, a nutrition expert for Boston University and spokesperson for the Academy of Nutrition and Dietetics.

Dextrin is a type of fiber. Soluble in water, and with a low viscosity, it should not negatively impact the mouthfeel of the beverage. Eating a diet rich in fiber can certainly have health benefits, says Blake. Because fiber stays in the stomach longer, keeping us feeling full, it can help decrease appetite, she says. And fiber attaches to some of the cholesterol in the digestive tract, preventing the body from digesting it and possibly helping lower blood cholesterol levels. But it isn’t clear that a dose of fiber in a drink will provide those effects. That requires “a fair amount of fiber, and from multiple sources,” says Blake. Suntory has not released nutritional information on Pepsi Special, nor disclosed whether it will be released in the United States.

Pepsi Special isn’t the only beverage with purported health benefits on the horizon. Coca-Cola recently announced that it will partner with French company Sanofi to launch four drinks claiming to do everything from improving your skin to fighting aging.