Green tea is made from the unfermented leaves of the Camellia sinensis plant. Widely consumed around the world, tea was first harvested and produced in India and China. Green tea contains the highest concentration of polyphenols, a type of antioxidant, than other types of tea produced from the same plant — black and oolong. While it has a number of health benefits, green tea also naturally contains caffeine, which, if consumed too late in the day or in too great of quantities can make it difficult for you to fall asleep.
Caffeine Content in Tea
Green tea naturally contains caffeine, although many types of green teas can be purchased already decaffeinated. The caffeine content in green tea, contrary to popular belief, is not necessarily less than other types of tea. Caffeine content in tea is dependent on a number of factors, including the age of the tea when harvested, the cultivar of the tea leaves, the growing method and environment, the manufacturing conditions, and the way it is prepared — for instance, how long the tea is steeped.
Green tea, like other teas, can be decaffeinated in three different methods. Commercial decaffeination uses either ethyl acetate or carbon dioxide to reduce the amount of caffeine in the leaves to less than 0.4 percent of the tea’s dry weight. Carbon dioxide decaffeination is considered the better option as more of the flavor and health benefits of the tea are preserved. An at-home decaffeination method not approved for commercial decaffeination is to steep the tea for a short period — around 20 seconds — and then toss out the water, making a new serving of tea with the wet leaves. Commercial decaffeination leads to a one to two-thirds reduction of all health benefits in teas, according to tea importer Tea Etc.
According to MedlinePlus, the amount of tea used in studies ranges from one to 10 cups per day, although the common amount of green tea is based on consumption in Asian countries, which is around three cups per day. This amount provides 240 to 320 milligrams of polyphenols per day, if the tea is made by steeping 1 teaspoon of leaves in 8-ounces of boiling water. According to the University of Maryland Medical Center, a cup of green tea contains between 50 to 150 milligrams of polyphenols per serving. If you are taking green tea extract, between 100 and 750 milligrams of extract is recommended.
Side Effects of Too Much Green Tea
Getting too much green tea in either extract or liquid form can lead to a number of side effects. In addition to difficulty sleeping, over-consumption of green tea can lead to constipation, diarrhea, nausea, a jittery feeling and a sense of restlessness. In some cases, an allergic reaction can occur from green tea, including hives, a tightening in the chest, difficulty breathing, swelling in your face, a rapid heartbeat and inconsistent mood swings or mental states. Seek medical treatment immediately if you experience any of these symptoms.
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