[cinntaile]

How can they cause weight gain when they contain no or a tiny amount of calories?

[Firmwarrior]

They don't satisfy your hunger or craving for sweets, so you end up eating more

[cinntaile]

But he compared it with a subjectively equal amount of sugar,so no additional food is eaten.

[hedora]

The involuntary part of your brain gets confused because it received an "I ate" signal from your mouth but not your stomach. It responds by panicking: lowered metabolism and increased appetite.

Both effects have been shown separately. For instance, mice on fixed calorie diets become lethargic and gain weight if artificial sweeteners are added to their water.

[cinntaile]

Has this been shown in humans? A lot of mice results don't replicate in humans.

[QuadmasterXLII]

In an extreme example, mood stabilizers such as Depakote strongly cause weight gain despite having no calories.

[tsol]

They still cause insulin release, and a resultant hormonal response

[jimbob365]

I don't think that's true. Here's a recent study disproving that: https://pubmed.ncbi.nlm.nih.gov/29982723/