When I was on Meridia I asked the doctor the same thing. His response was the fat has to go somewhere. I asked if that meant I was passing fats and he said yes. Now I could be completely wrong so be nice ! Also, when my BM's changed he said the same thing. Has anyone had their doctor tell them this? It might be worth someone with medical insurance calling their doctor's nurse and asking just this question! I do know when my stuff is yellow my weight goes down. Could be completely wrong, but if I am I can blame it on my doctor. Can't call him now because my insurance expired September 1st! Also, I have bad allergies, and have noticed that when I am losing weight my pores put out a yucky flower smell! Drives me crazy!