Consuming artificial sweeteners can activate the dopamine system, leading to increased cravings for them.

“So now, there's an artificial sweetener that's coupled with an actual increase in blood glucose. The natural world scenario where this would happen would be drinking a diet soda which contains no calories, and therefore, would not increase blood glucose, but is sweet, with a food that increases blood glucose. And when that happens, what you're essentially doing, is tapping into the dopamine system.”