Yes, green tea contains caffeine, but what I’m about to tell you may surprise you. The caffeine in green tea acts differently than the caffeine in coffee. In fact, it may have surprising benefits you don’t normally find in coffee.

First of all, while green tea does contain caffeine, it has far, far less caffeine than coffee. According to About.com (http://coffeetea.about.com/library/blcaffeine.htm), an 8 oz cup of brewed coffee can have up to 120 mg of caffeine. By comparison, 8 oz of green tea has only 20 mg– just one sixth the amount in coffee! Even black tea has just 45 mg of caffeine. Clearly, coffee is far and away a more stressful drink.

Why does tea have so much less caffeine? In part, it’s just a difference in the plants coffee and tea come from. Coffee’s made from beans, which concentrate caffeine in the same way a peach concentrates sugars. On the other hand, the tea plant spreads its own caffeine production across hundreds of leaves. What’s more, the preparation method of each drink draws out a different amount of caffeine. Most teas are prepared from whole leaves. This means the leaves are simply put in hot water and allowed to steep for a few minutes. Thus, much of the caffeine remains trapped in the leaf. With coffee, the bean is ground, increasing the surface area of the bean and thereby increasing the amount of caffeine that can be extracted. Add to it steam-based brewing methods, like those used with espresso, and you get a higher caffeine content.

While green tea has less caffeine than coffee, it also reacts differently with your body. After all, Zen monks use green tea to stay focused during long meditation sessions. Imagine if they tried that with coffee! Because tea contains the amino acid L-theanine, caffeine’s effects get mitigated over time. L-theanine has a calming effect on your nervous system. While coffee gives you a quick jolt of energy followed by a sudden crash, the caffeine in green tea gives you a sustained sense of alertness and focus. It’s ideal for late-night study sessions and a boost throughout your workday. Like many highly complex natural chemical reactions, the mechanism by which tea has this effect is poorly understood. Nonetheless, it’s been used by Asian monks for centuries to stay alert during long sessions of chanting and meditation.

Finally, the caffeine in green tea has (at least) one other beneficial effect. You’ve heard green tea touted as an aid for losing weight? Some medical research reported by the University of Maryland Medical Center (http://www.umm.edu/altmed/articles/green-tea-000255.htm) has indicated that green tea’s caffeine boosts the metabolism in some individuals. This metabolic boost, combined with a thermogenic effect that burns fat thanks to green tea’s catechin polyphenols, can aid in weight loss and weight control in lightly to moderately obese individuals.

So green tea has just the right amount of caffeine to give you a little boost in alertness and metabolism, along with a little weight loss to boot. Research is ongoing into this remarkable beverage, and the findings are often enough good news!

Author Bio: William Randall writes about tea culture for TeaHawk, a leading web site on all aspects of tea. Keep up with the latest research into tea’s health benefits here.

Category: Food and Drinks
Keywords: green tea, green tea caffeine