Green tea is made from the same leaves that black tea is made from, but it is less processed. Therefore, green tea retains more of the plant's natural benefits than black tea does. Green tea extract is a concentrated form of green tea, usually in capsule form, that allows one to receive higher doses of the substance than one could through simply drinking the tea.
Green tea has been used in traditional Chinese medicine since antiquity to treat physical pains, aid digestion, and prevent signs of aging. More recently, it has been discovered that green tea and green tea extract are a significant source of antioxidants, including epigallocatechin gallate (EGCG). Antioxidants are said to fight the free radicals that can cause cancer and dangerous infections.
Green tea extract is also claimed to have such benefits as lowering cholesterol, lowering blood pressure, and promoting heart and liver health. It is said to reduce stress and aid in cognition as well. Green tea extract has been used to treat such varied health conditions as Alzheimer's, multiple sclerosis, Human Immunodeficiency Virus (HIV), and arthritis.
Green tea extract has also become popular among dieters, as it is claimed to boost the metabolism and promote weight loss. Studies have shown that green tea extract can help a person burn up to 70 - 80 extra calories each day. In addition, green tea extract does not have the harmful side effects seen in many weight loss products.
While green tea extract may seem like a miracle product with so many claimed benefits, keep in mind that none of its health benefits have been accepted by the Food and Drug Administration (FDA). However, scientific studies continue to show promising results, and people living in areas with traditionally higher consumption of green tea, such as Japan, have been shown to have a longer life expectancy and less incidence of cancer than those from other cultures.