The Diet Soda Debate
Editor's note: This story was updated on Sept. 18, 2014.
July 31, 2014 -- When you’re trying to lose weight or keep off extra pounds, can diet soda help? While it has fewer calories than regular soda, some studies show it fuels your sweet tooth.
Also, are artificially sweetened sodas good for your health? Several studies this year continue the debate.
Better Than Water?
In late May, the journal Obesity published a study that aimed to determine what makes a bigger difference when attempting to shed pounds: water or diet soda? The researchers found that, on average, people who drank diet soda over the course of the 12-week study lost about 13 pounds, which was 4.5 pounds more than those who had switched to water. The diet-beverage drinkers also said they felt less hungry than those who drank water.
Lead researcher James Hill, MD, says his study’s results will ease the minds of diet soda drinkers who worry that it may derail their weight loss efforts, as some studies and media reports have suggested.
“The results make me confident that, at least when it comes to weight, it [diet soda] is OK,” says Hill, a professor of pediatrics and medicine and an obesity specialist at the University of Colorado, Denver. “It’s one less thing people have to worry about, and they have to worry about so much when it comes to weight loss.”
The study was funded by the American Beverage Association, and for some, that raises the question of bias in favor of no-cal sodas.
Michael Goran, MD, says the study outcomes were solid and the research findings were significant. “But industry-funded studies always send up a red flag," he says. Goran is a professor of preventive medicine, physiology and biophysics, and pediatrics, as well as director of the Childhood Obesity Research Center, at the University of Southern California’s Keck School of Medicine.
Hill says the study was thoroughly vetted by a peer-review process prior to publication. “If you’re worried about industry-funded research, look at the study with a very fine-toothed comb,” he says, “but, at the end of the day, evaluate the science.”
Earlier this year, in January, researchers at the Johns Hopkins Bloomberg School of Public Health reported that overweight and obese people who drink diet sodas tend to eat more calories during meals and from snacks throughout the day than those who drink sugary beverages, including regular soda. In adults with a healthy weight, the opposite was true: Those who drank sweetened beverages ate more than those who drank diet sodas.
Contrast this with a study published last year in the American Journal of Clinical Nutrition. It compared people who were randomly selected to swap their regular sodas for either water or diet drinks. The researchers found that both groups ate fewer calories and “showed positive changes in dietary patterns.” In fact, the diet-drink group ate fewer desserts by the end of the study than the water group, while the water group ate more fruits and vegetables.