Can artificial sweeteners cause weight gain?

There is some debate about whether artificial sweeteners contribute to weight gain.

Evidence for this is conflicting. Long-term studies with large sample sizes have found an association between artificial sweeteners and weight gain, but these studies tend to rely on diet questionnaires, which are not accurate.

They also can't say if diet soda makes you fat, or if overweight people are more likely to drink soda.

A report evaluated the results of many of the more rigorous short-term trials, concluding that artificial sweeteners actually aid weight loss by replacing sugar calories with non-calorie alternatives.