You might be aware of the original Stacker, which needs a bit of an explanation. It comes from the term used as stacking or "Stack", which in turn comes from the word ECA stack that is an acronym for the ingredients, which are ephedrine, caffeine and aspirin.
It became a well-known fast energy booster but also as a metabolism booster and a fat-loss burner that works. These days most of the ephedrine has been replaced with something that the manufacturers say will work exactly the same but is called the Proprietary Formula.
They are sold cheap and can be found for less than $20 for 100 tabs found in any discount store or a supermarket. Sold today all over the web but you should be careful that you are not buying the one with ephedrine.
The following is the list of ingredients in each tablet.
Kola Nut - Which the main source of caffeine found in all stack formulas.
The newly launched Stacker 2 makes some bold statements in its press release saying that it is "The World's Strongest Fat Burner". The manufacturers explain that the new "Proprietary Blend" they have created is something that has completely changed the effect that the ephedrine used to have and it producers no side effects.
Yerba Mate - Said to help with fat-loss although no clinical trials done yet.
Cassia Mimosoides - Which is a well-proven lipase inhibitor that theoretically will prevent the body from both absorbing and storing fat.
White Willow Bark - Which is the commonly used equivalent for aspirin in all Stack Formulas.
Caffeine Anhydrous - Depending on the quantity this is a mild thermogenic, which is also a terrific energy booster.
Green Tea - A well-proven fat-burner as well as its thermogenic benefits in.
Guggulsterones - Said to be the secret ingredient that stimulates the thyroid and directly affects the speed of metabolism.
Gymnema - Used for years in treating diabetes, which also reduces the sweet tooth in someone and can help with any diet.
Without the use of ephedrine there is obviously no guarantee that it will work as well as the original Stack did. With the guarantee that there will be no harmful side effects it seems that one could risk trying it knowing that effective and permanent fat loss is not guaranteed.
Most of the Stack combinations that you can now purchase rely on the fat-loss benefit to also come from the noticeable loss of appetite that all users get. If you include the extra thermogenic effect along with the increased BMR the results are only a matter of time.