Not for Pregnant Women or Nursing Moms

Since green tea contains caffeine -- one cup contains approximately 50 milligrams -- it is not recommended for women who are pregnant or breastfeeding.

Does the Green Tea Diet Work?

Some experts swear by green tea and say that the high levels of EGCG will help you shed those excess pounds. Others say it's not the EGCG but rather the caffeine in green tea that aids in thermogenesis and in the increased rate of metabolism. Still others claim that green tea alone really is not all that helpful as a weight-loss aid.

There are a number of ways in which a substance can help you lose weight. But two main weight-loss factors are the suppression of appetite and the increase of metabolism; green tea is said to do both. EGCG, that special antioxidant chemical, is said to increase metabolism and lower "bad" cholesterol [source: Pizzo]. Furthermore, it is suggested that EGCG may also help regulate glucose, or blood sugar levels, since it has the potential to act as a "carb-blocker," or to help inhibit the absorption of carbohydrates [source: The Hoffman Center].

It's important to keep in mind, though, that although there have been a few studies on the effectiveness of green tea as a weight-loss aid, results have been mixed. More studies are needed for conclusive evidence for or against the weight-loss properties of green tea. Furthermore, the Food and Drug Administration (FDA) does not regulate supplements such as green tea extract, so strength, effectiveness and safety aren't guaranteed [source: Mayo Clinic].

If you do choose to incorporate green tea diet pills into your weight-loss regimen, there are a few steps that may increase its effectiveness and that will help you maintain a healthy lifestyle. First, be sure to drink lots of water. Because many of the ingredients in green tea diet pills are diuretics -- which help rid the body of excess water -- it's important to stay hydrated.

Also, though many green tea diet pills don't contain as much caffeine as a cup of coffee, it's still important to realize that they do contain caffeine and therefore could cause side effects such as irritability or nausea if taken too often. Follow dosage instructions and pay attention to how your own body is responding to the pills -- if necessary, take the pills only a few days a week, or take only one pill a day. If drinking green tea, aim for two to three cups a day [source: University of Maryland Medical Center]. As with any diet or supplement, you should always talk to your doctor before starting a green tea regimen.

For more information on green tea and dieting, be sure to check on the links on the next page.