low-calorie sweets throws body's calorie detection out of whack

Some researchers think artificial sweeteners may actually interfere
with our efforts to diet. A 2004 study by psychologists at Purdue
University found that when rats were fed artificially sweetened liquids
for 10 days, they lost their innate ability to gauge the calorie
content of foods containing real sugar. In nature, the sweeter
the food, the greater the calories. Humans have adapted over millions
of years to seek out food that tastes sweet, and not just for survival.

Time