The study focused on diet drinks which contain the artificial sweetener aspartame. Researchers found that people who consumed diet drinks with aspartame felt hungrier than those who did not, and ended up consuming more calories.
In experiments, researchers found that aspartame may contribute to the development of a condition called "metabolic syndrome," which involves a cluster of symptoms, including high blood pressure, high cholesterol levels, and a large waist size.
The effects remained the same when study participants used artificial sweeteners in tea or coffee.
Other studies with mice show that artificial sweeteners could be causing people to absorb more glucose.
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