Guarana, Yerba Mate and Damiana
This is combined review of the herbs Guarana, Yerba Mate, and Damiana because when they are included in diet pills, they are often included as combination of the three. Also, the only supportive studies that I’ve found are on the combination of the three.
Guarana, Yerba Mate, and Damiana (GYD) has been shown to help in appetite suppression as it helps you feel fuller than you maybe you really are.
One study ((http://www3.interscience.wiley.com/journal/118993253/abstract)) showed gastric emptying of subjects when taking the GYD compound is prolonged significantly (from around 38 minutes for the placebo group to around 58 minutes for those taking GYD). In addition, those taking GYD lost around 5.1 kg over a 45 day period as opposed to .3 kg for the placebo group.
Unlike many other supposed appetite suppressants (like hoodia), it appears that Guarana, Yerba Mate, and Damiana (or at least the combination of the three) does, in fact, aid in weight loss by making you feel as though you are full. Thumbs up for GYD.