I would recommend against a stimulant, though green tea extract is indeed beneficial and has no negative side effects for most people. Basic supplements to suppress cravings and improve nutrient assimilation/uptake are things like l-carnitine, chromium, l-tyrosine, vanadium, fish oil, and a spectrum of B vitamins like Biotin (notably).
When I'm taking my supplements and free of deficiencies I sleep better, have less cravings, less blood sugar swings, and the like. Many folks notice improved weight loss, because at a cellular level your body is processing food more efficiently with the correct nutrients to break down and aid the processes.
Last edited by Arctic Mama; 10-30-2012 at 10:26 PM.
Reason: Typo fix