I've been on 400 mg for a long time, but I do remember a time when I was only on 200mg daily. I noticed that it did suppress my appetite and caused a bit of weight loss in the beginning. Also, it seemed to have counteracted the significant chance of weight gain that Seroquel/antipsychotics potentially cause, so overall, my weight has remained neutral. I'm on the thin side.

Therefore, it makes sense that it could cause weight loss in certain people, especially if you are not on any other meds where weight gain is listed as a major side effect. It doesn't seem to be listed as one of the meds that cause a lot of weight gain, so it should be more on the neutral side. Everyone is different though.