Diet Soda Drinkers Gain Weight

Overweight Risk Soars 41 Percent With Each Daily Can Of Diet Soda

(WebMD)  Diet Soda No Smoking Gun

Fowler is quick to note that a study of this kind does not prove that diet soda causes obesity. More likely, she says, it shows that something linked to diet soda drinking is also linked to obesity.

"One possible part of the explanation is that people who see they are beginning to gain weight may be more likely to switch from regular to diet soda," Fowler suggests. "But despite their switching, their weight may continue to grow for other reasons. So diet soft-drink use is a marker for overweight and obesity."

Why? Nutrition expert Leslie Bonci, MPH, RD, puts it in a nutshell.

"You have to look at what's on your plate, not just what's in your glass," Bonci tells WebMD.

People often mistake diet drinks for diets, says Bonci, director of sports nutrition at the University of Pittsburgh Medical Center and nutrition consultant to college and professional sports teams and to the Pittsburgh Ballet.

"A lot of people say, 'I am drinking a diet soft drink because that is better for me. But soft drinks by themselves are not the root of America's obesity problem," she says. "You can't go into a fast-food restaurant and say, 'Oh, it's OK because I had diet soda.' If you don't do anything else but switch to a diet soft drink, you are not going to lose weight."


The Mad Hatter Theory

"Take some more tea," the March Hare said to Alice, very earnestly.
"I've had nothing yet," Alice replied in an offended tone, "so I can't take more."
"You mean you can't take less," said the Hatter: "It's very easy to take more than nothing."
Lewis Carroll, Alice's Adventures in Wonderland

There is actually a way that diet drinks could contribute to weight gain, Fowler suggests.