All types of tea (green, black, and oolong) are produced from the Camellia sinensis plant using different methods. Fresh leaves from the Camellia sinensis plant are steamed to produce green tea.

Green tea is usually brewed and drunk as a beverage. Green tea extractextractto get, separate, or isolate a desired active ingredients can be taken in capsules and are sometimes used in skin products.

Green tea and green tea extractextractto get, separate, or isolate a desired active ingredients, such as its component EGCG, have been used to prevent and treat a variety of cancers, including breast, stomach, and skin cancers.

Green tea and green tea extracts have also been used for improving mental alertness, aiding in weight loss, lowering cholesterol levels, and protecting skin from sun damage.

Your health care provider may have recommended this product for other conditions. Contact a health care provider if you have questions.

Laboratory studies suggest that green tea may help protect against or slow the growth of certain cancers, but studies in people have shown mixed results.

Some evidence suggests that the use of green tea preparations improves mental alertness, most likely because of its caffeine content. There are not enough reliable data to determine whether green tea can aid in weight loss, lower blood cholesterol levels, or protect the skin from sun damage.

NCCAM is supporting studies to learn more about the components in green tea and their effects on conditions such as cancer, diabetes, and heart disease.

Green tea is safe for most adults when used in moderate amounts.

There have been some case reports of liver problems in people taking concentrated green tea extractextractto get, separate, or isolate a desired active ingredients. This problem does not seem to be connected with green tea infusioninfusionthe process of steeping or soaking plant material in hot or cold water to isolate its active ingredients or beverages. Although these cases are very rare and the evidence is not definitive, expert suggests that concentrated green tea extracts can be taken with food, and that people should discontinue use and consult a health care practitioner if they have a liver disorder or develop symptoms of liver trouble, such as abdominalabdominalrelating to the stomach and intestines pain, dark urine, or jaundice.

Green tea and green tea extracts contain caffeine. Caffeine can cause insomnia, anxiety, irritability, upset stomach, nausea, diarrhea, or frequent urination in some people.

Green tea contains small amounts of vitamin K, which can make anticoagulant drugs, such as warfarin, less effective.

Before taking any new medications, including natural health products, speak to your physician, pharmacist, or other health care provider. Tell your health care provider about any natural health products you may be taking.