Over 250 species of evergreen shrubs and trees make up this Asian genus. Many species are grown as ornamentals for their handsome, glossy foliage and fine flowers. The most important species commercially is C. sinensis (tea), native to China, which is cultivated on a vast scale and has over 350 cultivars. It was introduced to Europe in the 17th century. In addition to the various kinds of tea obtained from the leaves of C. sinensis, oil is extracted from the seeds, though the main source of tea seed oil is C. sasanqua, which yields higher amounts. Tea has been drunk in China for over 3,000 years. The ritual tea ceremony began in china during the Sung Dynasty (CE960-1279) and spread to Japan, where it remains close to the original. In legend, the origin of the tea is given as Buddha's eyelids, which he cut off and hurled to the ground when he fell asleep while meditating. Where they fell, tea plants arose so that he would have tea to bestow alertness. Tea contains about 50mg of caffiene per cup (compared with 85mg per cup of coffee) and 10-24 percent tannins, which are a possible cause of esophageal cancer. Drinking tea with milk eliminates this risk because the tannins are neutralized. Tea contains antioxidants known as polyphenols, which help protect against heart disease, strokes, and cancer. Levels of polyphenols are probably higher in green tea, since they may be degraded during fermentation in black tea. Research has also shown that a chemical extracted from tea may help destroy antibiotic-resistant organisms. Camellia seeds are rich in oil. The quantity and quality vary from species to species, and is used according to grade in cooking, cosmetics, and paint. The main species prized for their oil are C.crapnelliana, C. octopetala, C. oleifera, C. reticulata, and C. sasanqua. Camellia is named after George Joseph Kamel (1661-1706), a Jesuit pharmacist who wrote a history of Phillipine plants.

Black tea, like green tea, comes from the leaves of the Camellia sinensis bush, but unlike green tea, its leaves are fermented during processing. This produces health-enhancing substances called thearubigens and theaflavins, which are strong antioxidants that may help lower the risk of death due to heart disease.

Small, variable, evergreen shrub with leathery, elliptic leaves, 5-9cm (2-3½) long, and to 13cm (5in) in some varieties. White flowers, about 2.5cm (1in) across, with a boss of yellow stamens, are borne in the axils during winter, followed by capsules, containing large, oily seeds.

Common Name:
Other Names:
Black Tea, Black Leaf Tea, English Tea
Botanical Name:
Camellia sinensis syn Thea sinensis
Rich, moist soil in sun or partial shade. Bushes are normally pruned to 1m (3ft)
By seed sown as soon as ripe, or in spring, at 15-18°C (59-64°:F). Dried seeds need chipping. By semi-ripe cuttings in summer at minimum 18°C (64°F)
Leaves are picked during the year, from bushes over three years old, and dried for use in infusions or distilled in oil. Seeds are removed from capsules and pressed for oil, which is processed to remove saponins.
1-6m (3-20ft)
60cm-4m (2-12ft)
Parts Used:
Leaves (shoot tips only), essential oil (leaves), fixed oils (seeds), Stem.
An aromatic, slightly bitter, astringent herb that stimulates the nervous system and has diuretic and bactericidal effects.
Medicinal Uses:
Internally for diarrhea, dysentery, hepatitis, and gastroenteritis. Excess causes constipation, indigestion, dizziness, palpitations, irritability, and insomnia. Externally for sore eyes, minor injuries, and insect bites. Regular consumption of green tea may protect against arteriosclerosis and dental cavities and may help lower blood pressure and cholesterol.
To treat kidney stones, cardiovascular disease, Parkinson's disease, and headaches; to increase mental alertness; to reduce the risk of atherosclerosis.
Typical Dose:
A typical dose of black tea may range from one to several cups per day.
Possible Side Effects:
Black tea's side effects include nervousness, restlessness, insomnia, and gastric irritation.
Drug Interactions:
Taking black tea with these drugs may interfere with the absorption of the drug:
Amitriptyline (Elavil, Levate) Amitriptyline and Chlordiazepoxide (Limbitrol) Amitriptyline and Perphenazine (Etrafon, Triavil) Amoxapine (Asendin) Chlorpromazine (Thorazine, Largactil)
Clomipramine (Anafranil, Novo-Clopramine) Desipramine (Alti-Desipramine, Norpramin) Doxepin (Sinequan, Zonalon) Fluphenzine (Modecate, Prolixin) Imipramine (Apo-Imipramine, Tofranil)
Lofepramine (Feprapax, Gamanil) Melitracen (Dixeran) Mesoridazine (Serentil) Nortriptyline (Aventyl HCl, Pamelor) Perphenazine (Apo-Perphenazine, Trilafon)
Prochlorperazine (Compazine, Compro) Promethazine (Phenergan) Protriptyline (Vivactil) Thiethylperazine (Torecan) Thioridazine (Mellaril)
Thiothixene (Navane)
Trifluoperazine (Novo-Trifluzine, Stelazine)
Trimipramine (Apo-Trimip, Surmontil)
Disease Effects:
Increased risk of microcytic anemia in infants who are given tea.
Food Interactions:
  • May increase therapeutic and adverse effects of caffeine when taken together with caffeine containing foods and drinks.
  • May interfere with the absorption of nonheme iron (iron from sources other than meat) in the diet.
  • Milk can bind the antioxidants in black tea and decrease their beneficial effects.
  • Increased excretion of both calcium and magnesium when black tea is taken in large amounts.
Culinary Uses:
Leaves are steamed and dried for green tea, or fermented and dried for black tea. Tea is occasionally used as a flavoring, notably for boiling eggs, or as a soaking liquid for dried fruits and ham. Leaf extracts are fermented to make kombucha, or "tea cider". Powdered green tea is an ingredient in Japanese candy. Oil is used in cooking.
Ecomonic Uses:
Essential oil is used in perfumes with a leathery note, and in commercial food flavorings. Fixed oil is used in manufacturing paint.
Encylopedia of Herbs by Deni Brown Copyright ©: 1995, 2001 Dorling Kindersley Limited pg 151
The Essential Herb-Drug-Vitamin Interaction Guide by Geo. T. Grossberg, MD and Barry Fox, PhD, Copyright ©2007 By Barry Fox PhD. Pp. 82-83