WEDNESDAY, Sept. 25, 2002 (HealthDayNews) -- If you're addicted to sodas, you might want to switch to artificially sweetened ones to avoid gaining weight.
So say Danish scientists who conducted a study of 41 overweight, middle-aged people for 10 weeks, asking them to add sweet drinks to their regular diet. Half the participants were given sucrose-sweetened drinks and half were given drinks sweetened with artificial sweetener. Participants were not told which type of beverage they were drinking.
Those whose drinks were sugar-sweetened gained an average of three pounds, while those who drank diet drinks lost a little more than two pounds on average.
"We were astounded that these soft drinks could change weight that much. We didn't expect soft drinks to have this fattening effect," says Dr. Arne Astrup, a nutrition professor in Copenhagen and an author of the study, which appears in the October issue of the American Journal of Clinical Nutrition.
Astrup says that, normally, when you introduce more calories into a diet, people automatically compensate by reducing their calorie intake in other areas so they don't gain any weight. Such internal regulation comes as the stomach sends signals to the brain when the body is satiated.
However, this did not happen when people drank the sweetened drinks, which totaled at least a liter a day.
"It is possible that if it's a drink, it will simply pass through the stomach and go into the small intestine so a person doesn't feel full from the calories," he says. People continue to eat or drink more than they need, and gain weight.
The study's findings, he says, have changed his mind about what should be emphasized in a weight-loss program. Astrup treats overweight people as the director of the nutrition at the Royal Veterinary and Agricultural University in Copenhagen.
"If you asked me two years ago about the problems of losing weight, I would've said that sugar isn't the bad guy, that you should concentrate on fat reduction alone. But now I've totally changed my mind. I'm convinced that soft drinks are a major issue," he says. "I have patients who drink three or four liters of Coke a day because they think that because it has no fat they can have as much as they want. Now I tell them they may have a problem and that if they have to have soda, it should be artificially sweetened."
Further, he adds, "There has been an explosion in the consumption of soft drinks, and this could be a significant factor in the increase in obesity."
Connie Diekman, director of nutrition at Washington University in St. Louis, says the study, though small, is interesting and helpful.
"Ten weeks isn't a lifetime and 40 people is a small number, but there has been a concern about sweetened beverages, and this study is significant," she says. "It is one more study to put on my list to show that beverages as a source of calories don't give us the same satisfaction as solid food."
"It takes about 20 minutes of eating for the stomach to tell the brain that it's full," she adds, "and when we're looking at calorie control, we ought to think about spending calories on foods that take longer to consume and allow our bodies to feel the satisfaction from food."
Another finding in the study was that the participants who drank the sucrose drinks had a significant increase in blood pressure, an average increase of between 5 percent and 10 percent during the course of the study, Astrup says.
"It may be that sugar stimulates the sympathetic nervous system," he says, which is the body's high alert system to deal with stress or danger.
What To Do
To see a chart of the components of common soft drinks, both regular and diet, you can go to the National Soft Drink Association. The Physicians Committee for Responsible Medicine rates the top weight-loss books on the market.
