Zantrex-3 is one of the newest self-touted "super pills" to hit the competitive diet supplement market in recent years. Its marketing material boasts "546% more weight loss" than other brands - a statistic that is difficult to verify or investigate. There are no citations to clinical trials except for a reference to one study performed on an insignificant sample size of 47 people over 45 days, all who lost an average of 11.2 pounds.
Zantrex-3 promotes itself as a xanthine-based stimulant, which is another way of saying caffeine. Like similar fat-loss catalysts Xenadrine and Hydroxycut, Zantrex-3 contains caffeine-rich ingredients like yerba mate, guarana seed and green tea, making a dose the equivalent to drinking 3 to 4 cups of coffee. Caffeine can stimulate the metabolism and act as a mild diuretic, which may slightly speed up weight-loss in people who eat a low fat diet and perform regular exercise. Other herbal ingredients include ginseng, kola nut and damiana, a South American shrub that affects the nervous system.
You may, indeed, loose a few pounds when taking Zantrex-3 especially if you are also watching your food intake and activity level. However, it probably won't lead to a dramatic dip in the scale. Most likely, you will experience caffeine-related side effects such as the jitters, restlessness, sweating and increased urination. Plus expect to crash with some withdrawal symptoms after you stop taking Zantrex-3. Caffeine can be addictive.
More serious side effects include anxiety, elevated heart rate, high blood pressure, nausea, stomach ache, shaking, irritability and diarrhea.