How Green Tea Extract Can Help You Control Your Appetite & Reach Your Happy Weight

Who doesn't occasionally dream of a magic pill that will help you reach all your wildest health goals? While science has yet to make that wish a reality, some people are saying nature may have already done the work for us. Enter green tea extract. Supplement manufacturers are infusing this concentrated form of green tea into products that promise to help us control our appetites and reach our happy weights—naturally and without any side effects.

This super-concentrated version of green tea comes in powders, pills, and liquids that you can take during or after a meal to help boost your metabolism. And there's good science to back it up: One study1 found that when 12 healthy men ingested green tea extract capsules and exercised for 30 minutes, their fat oxidation rates were 17 percent higher than when they consumed a placebo.

The secret lies in green tea extract's high concentration of antioxidants called catechins, which have been correlated with3 a reduction in body fat. Green tea extract's high caffeine content also likely plays a role in its weight loss benefits. One study4 found that people who consumed high amounts of caffeine and green tea lost more weight and fat mass than those who consumed less of it. Other research, published in Food Science and Biotechnology5, found that caffeine can actually signal the body to break down fat. So it's likely that the caffeine and antioxidants work in tandem as a catalyst for weight loss.

“When the green tea extract goes into the body, the antioxidants and caffeine enter the cells and help the body burn calories and fat,” said Liana Werner-Gray, a health and nutrition coach who specializes in weight loss at Complete Wellness NYC. "Green tea extract is a good, natural way to lose weight. We have so many studies to back it up."

With all that being said, it's important to be realistic about how much weight you can lose with the extract alone.

"If the only thing you change about your life is adding green tea extract, without doing anything else differently, you can expect to lose up to half a pound in a month," said Werner-Gray. Green tea extract's weight loss properties are backed by reputable scientific research, but you should pair the supplement with other healthy changes for the best results. You're going to want to pair the extract with lifestyle tweaks like limiting gluten, dairy, and preservatives, eating whole, unprocessed foods, exercising regularly, and reducing stress wherever you can.

Another thing you might see if you start taking green tea extract is—hallelujah!—reduced inflammation. Studies show that the polyphenols in green tea are potent in antioxidants that could make it a viable treatment6 for chronic inflammatory diseases, such as Crohn's disease, pancreatitis, and hepatitis.

While most weight loss supplements come with a myriad of scary downsides, there are only a few side effects of green tea extract to watch out for. The most common you'll experience when you start taking green tea extract is a quick burst of energy, like you just had a shot of espresso. If you've ever had too much coffee, you know the icky experience of feeling jittery and unable to focus that sometimes follows this rush, so be careful if you're sensitive to caffeine. And if you have trouble sleeping, avoid taking green tea extract late in the day.

A few more things to consider: Just like a cup of most kinds of tea, green tea extract acts as a diuretic. Make sure to drink lots of water throughout the day to help avoid dehydration. If you have gastroesophageal reflux disease (GERD), you may want to steer clear too, since green tea has been shown to spur symptoms like heartburn and regurgitation.

And one study in the journal Cancer Prevention Research12, which evaluated more than 1,000 women, found that a portion of the participants who took a very high dose of green tea extract developed abnormalities in their liver function.

"It's safer than coffee, alcohol, and a lot of other things, but it can be taxing on the liver," said Werner-Gray. So if you have a liver disease or disorder, like hepatitis or hemochromatosis, be sure to talk to your doctor before adding any supplement to your diet.