I have used many fat burners lipo 6 hydroxy cut black mamba,but feel just a little sweat or energy as my body is very big....but i swear i have taken one pill of this on empty stomach and my god i feel shivering in my body for 3 to 4 hrs...although i do not really respond to stimulants....so i cant say how it will effect my body fat...but i am sure if keep my diet in check and calorie deficit this will help me to loose some more body fat...looking forward to it