Where does tea come from?

All tea comes from the leaves of one plant, Camellia sinensis, which is processed into four tea types — White, Green, Oolong and Black.  At right, tea is pictured growing on a plantation.

Local conditions in the various tea-growing regions of the world determine a tea's characteristics, and one tea type can be quite different from another of its type in color, body, flavor and aroma.

What makes one tea different from another?

Green, Oolong and Black Teas all come from the upper leaves of Camellia sinensis, while White Tea consists only of leaves from the branch tips — particularly the leaf bud and possibly the first two leaves under the bud. Additionally, White Tea is picked once a year in the spring and is thus less available than the others.

For all four teas, the main point differentiating them comes from processing. After being picked from the Camellia sinensis plant, both White and Green Teas remain as unoxidized teas, Oolong Tea is partially oxidized, and Black Tea is fully oxidized. Oxidation occurs when enzymes in the tea leaves are released and the leaf responds to the oxygen in the environment, causing the leaves to turn a bright copper color.

White Tea is minimally processed — the leaves are only lightly steamed or, sometimes, just dried. In Green Tea, the leaves are steamed and/or pan fired, then they are rolled and dried. Leaves for Oolong Tea are partially oxidized (more than Green Tea, less than Black Tea), then dried. Black Tea is fully oxidized. This processing — all from the leaves of the same plant — is what gives tea types their differences in names and flavors.

Basically, processing gives Black Teas a more full-bodied and robust taste and Green Teas a more delicate, fresh taste, while Oolong Teas fall somewhere in between. Since only the tips are used and the processing is minimal, White Tea has the most delicate flavor of all.

Do all teas have the same caffeine content?

Since all teas are produced from Camellia sinensis, they naturally contain caffeine. Processing other than decaffeination does not change the caffeine content. All teas have approximately the same amount of caffeine, falling within a range of 25 to 60 mg of caffeine in a 6-oz. cup. For comparison, coffee has about 120 mg per 6 ounces.

What is the optimal water temperature to make Black Tea?

Black Teas should be infused with water that has just come to a boil--approximately 210-212 °F. It can be steeped 3 to 5 minutes, depending on the cut of the leaf. For green and white teas, the water should be slightly cooler at around 165-185°F (75-85°C), depending on the tea.

What are the health benefits of tea?

Tea is among the richest natural sources of antioxidants, which have been linked with cancer prevention, decreased risk of stroke, and reduced blood cholesterol.  Additionally, it has trace amounts of various nutrients such as the amino acid theanine; the minerals calcium, magnesium, manganese and potassium; and the vitamins C and K.

Based on the available scientific research, tea and tea flavonoids have also been shown to help strengthen the body’s immune system, protect teeth by inhibiting plaque bacteria, potentially fight free radicals produced during strenuous exercise, and possibly increase calories burned during everyday activities.

While this emerging research is promising, more studies on the role of tea and tea antioxidants must be completed before drawing any conclusions about tea’s contribution to health and wellness.

What are antioxidants and what are their benefits?

Naturally occurring antioxidants are nutrients found in most plants, including fruits and vegetables. The process of breaking down food for energy creates free radicals and peroxides in your body everyday. Antioxidants help your body keep these harmful substances in check. They bind free radicals and peroxides — both of which are oxygen-containing molecules in your body that, if left unchecked, can damage your DNA, lipid and protein in your body.

All teas are rich in antioxidants, including a class called flavonoids. Green Teas contain more of the simple flavonoids called catechins, while the oxidization that the leaves undergo to make Black Tea converts these simple flavonoids to the more complex varieties called theaflavins and thearubigins.

What is theanine and what is its role?

Tea comes from Camellia sinensis, the only plant that makes theanine. Unique to tea, theanine is a major amino acid in black, green, and oolong tea. Theanine is thought to be manufactured in the root of the plant and to be used by the plant to make tea flavonoids in the leaf. There are two forms of theanine which are mirror images of each other. One of these forms, L-theanine, makes up 98% of the theanine found in tea.

Theanine, a unique amino acid found in tea, activates specific cells involved in the “first line of defense” cells of the immune system, which may reduce the risk of viral and bacterial infections. This suggests that regular tea consumption may help support the body’s immune system.

Exciting recent research has shown that theanine may play an important role in the natural gentle stimulatory effects of drinking tea. Several studies have found that
L-theanine, the predominate form of theanine found in tea, stimulates alpha-brainwaves which are associated with a relaxed but alert mental state of mind. Theanine appears to work quickly and seems to be most effective when someone is stressed and the mind is preoccupied by many thoughts. It seems to help relax the mind allowing one to focus on the task at hand. Because theanine helps the mind stop racing it also seems to help promote a more restful, sound sleep because sleep is also not interrupted by random thoughts.

The science of theanine is just developing and it is not known if the effect of theanine is cumulative, but it does appear that the rejuvenating effects of tea on mood, cognitive function and psychomotor performance, that cannot be solely explained by the caffeine in tea, may be in part be due to theanine.

What is the potential role of tea in helping maintain healthy weight?

The possibility that green tea helps with weight loss has been a recent topic in the media. While this is an active area of research; the preliminary evidence suggests that tea drinking can increase energy expenditure and fat burning. However, there are no conclusive studies that tea drinking has beneficial effects on weight loss. Still, tea is a satisfying, calorie-free beverage that can be substituted for sweetened beverages and is a delicious alternative to plain water in a healthy weight management plan.

Can I drink brewed Tea hot or iced and get the same health benefits?

Yes. Antioxidants are equal in brewed teas whether they are hot or iced, but not necessarily in instant teas because some of the antioxidants are lost during the additional processing. However, you should avoid adding a lot of ice to regular tea to prevent the formation and precipitation of non-soluble complexes with caffeine.

Does adding sugar, honey, lemon or milk affect Black Tea's health benefits?

Research findings suggest that adding sugars, sweeteners, lemon and milk do not appear to affect the antioxidant levels of tea flavonoids.