Does diet soda make you fat?
A study just published in the American Journal of Public Health, that included almost 25,000 participants, showed that overweight and obese diet soda drinkers tended to consume significantly more solid-food calories per day than overweight and obese people who drank non-diet (i.e., sugar-sweetened) sodas.
Consumption of diet soda by healthy-weight people doesn’t have the same effect.
It’s a bit confusing, but in a nutshell, you’ve got two groups of people who are overweight/obese. One drinks diet soda, the other drinks regular (sugary) soda. For some reason, the overweight/obese diet soda drinkers actually ate more calories per day than the overweight/obese regular soda drinkers.
But that’s only among overweight/obese people. Among people who have a healthy weight, those who drank diet soda ate fewer calories during the day than those who drank regular soda.
According to the study’s abstract, “the net increase in daily solid-food consumption associated with diet-beverage consumption was 88 kilocalories for overweight and 194 kilocalories for obese adults.”
One of the authors, Dr. Sara Bleich cites previous research to try to partially explain the results. She says that artificial sweeteners may interfere with the way the brain normally senses “sweetness.” If you drink sugar containing beverages, the increased sugar in the blood makes the brain think that you are full and you stop eating. The artificial sweeteners don’t produce the same effect. They seem to make the brain sense that you are less full and allow for continued eating.
So overweight or obese people who drink diet soda may, in actuality, be causing an increase in their appetites. For some reason, this isn’t the case in normal-weight people.
Health-weight people who drink diet soda consume fewer calories on a daily basis than Health-weight people who drink sugar- sweetened soda. In the normal-weight group, there is usually no significant weight gain irrespective of whether they drink sugar containing or diet sodas. The authors don’t have an explanation for why this happens. Additional research will be necessary to discover the mechanism for this.
The authors recommend that overweight and obese people who drink diet soda closely monitor and restrict calories in an effort to lose weight since diet soda seems to be having an effect opposite to the one desired. They advocate for balancing caloric intake with caloric expenditure through exercise.