Diet soda may seem like a good way to enjoy the fizz and flavor of soft drinks without the calories. But if you drink diet soda to cut calories, a new study suggests it’s probably not working very well. Researchers studying the eating habits of diet soda drinkers have found that they’re likely to compensate–perhaps overcompensate–for the lack of calories in soda by eating more junk food throughout the day
For the study, published in the Journal of the Academy of Nutrition and Dietetics, researchers analyzed data from 22,000 people who participated in the National Health and Nutrition Examination Survey, NHANES, an ongoing project that tracked these people throughout a ten-year period. They found that those who regularly drank diet soda ate more of what they called “discretionary foods,” described as “energy dense,” and “nutrient poor”—otherwise known as junk food.
Among the participants, 90 percent reported eating junk food. Those who drank diet soda most often, ate the most junk food An average of about 482 calories a day from cookies, candy, French fries and ice cream. But even though they ate the most junk food, the diet soda drinkers didn’t consume the most calories. The alcohol drinkers did.
However, the tendency to eat discretionary foods among the diet soda drinkers led the researchers to suggest they could be compensating for the lack of beverage calories with empty calories from junk. Not exactly what you would call a healthy diet, regardless of the calorie count.
Brain, hormone effects
Researchers have been searching for answers as to why the widespread availability of zero calorie beverages has been no help for curbing America’s obesity epidemic. For example, a 2013 study published in Trends in Endocrinology and Metabolism found that diet sodas affect the brain differently than regular, sugar sweetened sodas.
Brain imaging revealed that real sugar activated reward centers of the brain, while artificial sweeteners did not. The illusion of sweetness on the tongue isn’t registering with the brain. Compared to real sugar, artificial sweeteners also had less effect on the release of hormones important in maintaining normal blood sugar levels after a meal, which could drive a person to seek more calories.
Other research has suggested that the calorie deficit created by drinking low or zero-calorie beverages leads people a believe they have license to indulge in foods with high calories,sugar, fat and salt.
Industry funded study
When it comes to weight loss, the only recent study known to link drinking diet soda to losing weight is research published in 2014 sponsored by the American Beverage Association, an industry group that includes Coca-Cola Co. and Pepsico as its more prominent members. In this 12-week study, heavy diet soda drinkers were enlisted in a weight loss program. Those who were allowed to continue drinking diet soda lost more weight than those who weren’t allowed to indulge.
It makes sense that adding a form of deprivation would make it less likely for one group to succeed during a 12-week program. But a large body of research suggests that in the long run, diet soda drinkers are less healthy, and weigh more, than people who avoid them.