Kukicha twig tea is also harvested from camellia sinensis, but uses twigs and stems rather than leaves.
The name sinensis means Chinese in Latin. Camellia is taken from the Latinized name of Rev. Georg Kamel, S. Though Kamel did not discover or name the plant, Karl von Linnaeus , the creator of the system of taxonomy still used today, chose his name for the genus of this tree to honor Kamel's contributions to science. Older names for the tea plant include Thea bohea , Thea sinensis and Thea viridis. Camellia sinensis is native to mainland South and Southeast Asia , but is today cultivated across the world, in tropical and subtropical regions.
It is an evergreen shrub or small tree that is usually trimmed to below two metres six feet when cultivated for its leaves. It has a strong taproot. The flowers are yellow-white, 2. The seeds of Camellia sinensis and Camellia oleifera can be pressed to yield tea oil , a sweetish seasoning and cooking oil that should not be confused with tea tree oil , an essential oil that is used for medical and cosmetical purposes and originates from the leaves of a different plant.
The leaves are 4—15 cm long and 2—5 cm broad. Older leaves are deeper green. Different leaf ages produce differing tea qualities, since their chemical compositions are different. Usually, the tip bud and the first two to three leaves are harvested for processing. This hand picking is repeated every one to two weeks. The three most common types of tea are green, oolong and black others include yellow, white, compressed and flavoured teas.
All use the same leaves of the same plant. Green tea is steamed Japanese method or roasted Chinese method very soon after picking to stop the oxidation process. Oolong tea is left to oxidize a bit longer and is the type used by most Chinese restaurants. Black tea is oxidized for the longest period of time which produces the darkest of the teas. White tea, a delicacy in the orient now beginning to be found in Western shops, is made from "tea needles," the newest, still folded shoots of leaves at the end of branches.
Further distinctions are made to denote the size of the leaves used the youngest, smallest leaves are generally held to have the highest quality flavor , and the region of origin in much the same way wine is classified. Studies have credited them with cancer-fighting properties 1.
Antioxidant compounds neutralize harmful molecules called free radicals. They help prevent and fight diseases that can occur when free radicals build up in your body, causing a state called oxidative stress 4. EGCG is the most potent and predominant of these 1 , 5 , 6 , 7.
Caffeine is the most studied stimulant compound in coffee and tea. As a stimulant, caffeine may also increase alertness, reduce fatigue, and improve exercise performance and mental functioning 12 , That said, consuming too much caffeine can cause potentially dangerous health effects, such as an irregular heart rate L-theanine is a non-protein amino acid derived from the tea plant. Furthermore, L-theanine has anti-inflammatory and antioxidant effects and is associated with improved immune function 15 , 16 , In addition to the three main compounds above, tea leaf extract contains B vitamins , lipids such as linoleic and alpha-linolenic acids, and trace minerals, including magnesium, calcium, iron, zinc, and selenium 3.
Camellia sinensis leaf extract has a long history of use in the cosmetic industry due to its positive effects on skin health and appearance. Due to the antioxidant potential of EGCG, it may protect the skin from damage from ultraviolet radiation UVR , which causes sunburn and may lead to premature skin aging and nonmelanoma skin cancer 18 , 19 , Furthermore, research shows that applying the extract topically and taking it orally reduces scaling and increases blood flow to the skin, skin elasticity, hydration, and density 18 , It may also help reduce wound healing time and may decrease excess sebum production — one main characteristic of an oily face 18 , People use Camellia sinensis leaf extract widely to improve skin health and appearance.
These effects are mainly due to its antioxidant and caffeine contents. Taking Camellia sinensis leaf extract or drinking tea may help improve heart health. Its compounds may reduce the enlargement of the heart, improve blood pressure dysfunction, and restore antioxidant enzyme activity Camellia sinensis leaf extract may improve heart health by lowering blood pressure, cholesterol, triglycerides, and preventing plaque buildup in the blood vessels. Test tube and animal studies have found that EGCG offers a cancer-protective effect by inducing apoptosis — or programmed cell death — in cancerous cells 3 , 23 , 28 , 29 , Additionally, it may help prevent tumor progression and spread by inhibiting angiogenesis.
This is the growth of new blood vessels that would otherwise feed cancerous cells 23 , 25 , 28 , Furthermore, EGCG increases the activity of antioxidant enzymes in your body, which neutralize free radicals.
Excessive amounts of free radicals can damage your DNA, contributing to the development of cancer 28 , 29 , Studies show that L-theanine may potentially enhance T-cell production.
T cells are a type of white blood cell that fights disease Therefore, it may play an important role in combating infections, allergic diseases, and hypersensitivity reactions L-theanine and EGCG in Camellia sinensis leaf extract may boost your immune system and help your body fight infections and viruses.
Research shows that L-theanine promotes relaxation and reduces anxiety by increasing levels of dopamine and serotonin. Brain cells produce these two signaling molecules, and they regulate motivation and happiness, among other functions Camellia sinensis leaf extract offers a calming effect mostly due to its L-theanine content, which promotes relaxation and reduces anxiety. Studies show that both the EGCG and caffeine in Camellia sinensis leaf extract may help increase weight loss EGCG may promote weight loss by inhibiting enzymes that cause the body to absorb and digest carbs and fat from the gut.
This may help lower energy intake 23 , 45 , 46 , Additionally, it may influence gut microbiota and induce weight loss by regulating fat metabolism and increasing fat breakdown 45 , 46 , 47 , Tea plants will grow into a tree if left undisturbed, but cultivated plants are pruned to waist height for ease of plucking. Two principal varieties are used, the small-leaved Chinese variety plant C.
Assam tea comes from the northeastern section of the country. This heavily forested region is home to much wildlife, including the rhinoceros. Tea from here is rich and full-bodied.
It was in Assam that the first tea estate was established, in Darjeeling — the Darjeeling region is cool and wet, and tucked in the foothills of the Himalayas. The tea is delicately flavored, and considered to be one of the finest teas in the world. The Darjeeling plantations have 3 distinct harvests, termed 'flushes', and the tea produced from each flush has a unique flavor. First spring flush teas are light and aromatic, while the second summer flush produces tea with a bit more bite.
The third, or autumn flush gives a tea that is lesser in quality. Nilgiri tea comes from an even higher part of India than Darjeeling. This southern Indian region has elevations between 1, and 2, metres.
The flavors of Nilgiri teas are subtle and rather gentle. They are frequently blended with other, more robust teas. The Chinese plant sometimes called C. It is native to southeast China.
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