Ultimate Herbals Guide: Green Tea

Green Tea: Your Herb Guide

What is Green Tea?

This Herb Guide provides everything you need to know about green tea- it’s common names, how and why it’s used, whether it works and what it works for best, research conducted, whether it’s safe and effective to use and the potential side effects and cautions.

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.

Common Names - Green Tea, Chinese Tea, Japanese Tea

Latin Name - Camellia Sinensis

What is Green Tea used for?

Green tea and green tea extracts, such as its component Epigallocatechin Gallate (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.

How is Green Tea used?

Green tea is usually brewed and drunk as a beverage. Green tea extracts can be taken in capsules and are sometimes used in skin products.

What the Science Says

Has Green Tea been scientifically proven to be safe and effective?

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.
The National Center for Complementary and Alternative Medicine is supporting studies to learn more about the components in green tea and their effects on conditions such as cancer, diabetes, and heart disease.

Side Effects and Cautions

Is it safe to drink Green Tea and what should I be careful of if I use it?

Green tea is safe for most adults when used in moderate amounts.
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.
Tell your health care providers about any complementary and alternative practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

Content Created/Medically Reviewed by our Expert Doctors