Aurora, Colo./University of Colorado -- A new study challenges the understanding that diet soda is bad for one's health. Researchers published their findings in the journalObesity, showing an additional 4lb. weight loss for those who drank diet soda than those who drank water.

The 303 participants were split into two different groups; one group had to stop drinking the diet soda, but the other group that kept drinking over a 12-week period lost an additional four more pounds. Researchers from the University of Colorado Anschutz Health and Wellness Center in Aurora, Colo., along with Temple University's Center for Obesity Research and Education in Philadelphia, Pa., looked at whether drinks such as Coke Zero, Diet Dr. Pepper, and Diet Snapple could help people lose more weight than drinking water alone. Although the study resulted in weight loss, experts believe it may just be a matter of willpower.

"It makes sense that it would have been harder for the water group to adhere to the overall diet than the (artificially-sweetened beverage) group," said Dr. Jim Hill, a professor of pediatrics and the director of the weight loss program at the University of Colorado's Anschutz Health and Wellness Center.

When people are put on a diet, the difficulty can be rated to the amount a person has to give up in order to adhere to the diets’ rules. If a person does not have to give up his or her regular diet soda drink, then following all of the diet rules is not as much of a challenge, since he or she is able to continue the usual food restrictions, which is what led to the 4lb. weight loss. The research was funded by the American Beverage Association.

Those who “are heavy users of noncaloric sweeteners” were the ones who have successfully lost a significant amount of weight, Hill recalls from his clinical experience. "The results, to us, were not at all surprising," Hill said.

The participants who only drank water during their diets lost 9 lbs., while the ones who drank diet soda lost 13 lbs. in the total 12-week period. Some 64% of those who drank diet soda lost at least 5% of their body weight, which has shown to significantly improve health by lowering the risk of heart disease, high blood pressure, and type 2 diabetes.

According to the National Institutes of Health, diet beverage drinkers who are overweight and obese adults, consume more calories from food than those who drink sugary beverages. A study group of 24,000 adult participants, age 20-and-older, were asked to  report all the food and beverages they had consumed in the last 24 hours. They found that 11% of diet beverage drinkers were healthy weight people, 19% were overweight, and 22% were obese adults.