I have never found a study that supports this.

The research is pretty clear this is from ghrelin stimulating appetite and at the same time altering levels of leptin so a person feels less full.

It is not from a blood sugar crash.

While some studies link lower BMI, meta analysis shows cannabis is kind of a disaster if you are trying to lose weight.

It is hard to make generalizations though because it is so different if you smoke once a month, once a week or once a day.