Tea: warm, soothing, healthy -- and the most popular drink in the world. The beverages known as tea are divided into two major groups: true teas, which are brewed from leaves of Camellia sinensis, the tea plant; and herbal teas, brewed from plants other than the tea plant. Black, green and white tea are all brewed from Camellia sinensis leaves. The distinct colors, aromas and flavors of the varieties of true tea arise from differences in harvesting and processing. All of the true teas are rich in antioxidants, and all contain caffeine, though the levels differ.
Favorite of everyone in Britain from the Queen to Mary Poppins, black tea is made from the dried and oxidized leaves of the Camellia sinensis plant. According to the UK Tea Council, about 165 million cups of tea are consumed in the United Kingdom every single day, an average of 2 to 3 cups per person per day. Black tea boosts energy with 33 to 50 milligrams of caffeine per cup. It is also a good source of cancer-fighting antioxidants. And yes, black tea can stain your pearly whites, but it is also a natural source of cavity-fighting fluoride.
Green tea is the drink of choice in China, Japan and other Asian countries. This tea is prepared by steaming and then drying the tea leaves. Like black tea, green tea enhances your defenses with polyphenols and other antioxidants. Consumption of green tea increases HDL or "good" cholesterol, helps lower hemoglobin A1C levels -- a measure of long-term blood sugar -- and reduces the risk of several cancers. Green tea also contains caffeine, about 24 to 40 milligrams per cup.
White tea is the rarest and most expensive preparation of the Camellia sinensis plant. This tea is made from the young leaves and buds of the plant, which are steamed immediately after picking. The tea is named for the white hairs visible on these young leaves. When brewed, white tea has a delicate aroma and a subtle flavor, and is lighter in color than black or green tea. White tea is very rich in polyphenols and contains only about 15 milligrams of caffeine per cup.
Although Camellia sinensis is considered a medicinal herb, the phrase "herbal tea" refers to beverages made from plants other than the tea plant. Herbal teas can be made from a wide range of plants -- chamomile flowers, ginger root and mint leaves are some favorites -- and do not contain caffeine. An herbal brew is referred to as a tisane if the water is heated first and removed from heat before the herbs are added; or a decoction, if the herbs are added to boiling water and simmered like soup.
Stephanie Draus is a naturopathic doctor and assistant professor of clinical sciences at National University of Health Sciences. She has practiced in Chicago as a health consultant since 2005. She is a graduate of the National College of Natural Medicine in Portland, Oregon.