Like beverages made from true teas, herbal teas can be served hot or cold. Herbal teas have been used for nearly as long as written history extends. Documents have been recovered dating back to Ancient Egypt and Ancient China that discuss the enjoyment and uses of herbal teas. Among the Chinese, herbal teas are commonly known as liang cha (Chinese: 涼茶; pinyin: liáng chá; Jyutping: loeng4 caa4).
Herbal teas are often consumed for their physical or medicinal effects, especially for their stimulant, relaxant or sedative properties. The medicinal effects of certain herbs are discussed under herbalism. The medicinal benefits of specific herbs are often anecdotal or controversial, and in some countries (including the United States) makers of herbal teas are not allowed to make unsubstantiated claims about the medicinal effects of their products.
Available as pure or blended samples, herbal teas are popular because of their fragrance, antioxidant properties and therapeutic applications. The antioxidant properties (AOP) of herbal teas from temperate plants of mainly Lamiaceae have been well-studied while those of tropical herbal teas are less well-studied. Recently, a comparative study showed that tropical herbal teas were more diverse in types and more variable in AOP values than temperate herbal teas. Herbal teas generally had lower antioxidant values than true teas. Exceptions were lemon myrtle, guava, and oregano teas with antioxidant properties comparable to black teas.
As herbal teas can be composed of any plant material, including some plants that are known to be toxic, the specific ingredients must be checked for health and safety individually. Most retail herbal teas sold as beverages could be considered safe, but medicinal herbal teas could easily contain herbs that cause damage in large amounts.
While most herbal teas are safe for regular consumption, some herbs have toxic or allergenic effects. Among the greatest causes of concern are:
Herbal teas can also have different effects from person to person, and this is further compounded by the problem of potential misidentification. The deadly foxglove, for example, can be mistaken for the much more benign (but still relatively toxic to the liver) comfrey.
The UK does not require herbal teas to have any evidence concerning their efficacy, but does treat them technically as food products and require that they are safe for consumption.
Depending on the source of the herbal ingredients, herbal teas, like any crop, may be contaminated with pesticides or heavy metals. According to Naithani & Kakkar (2004), "all herbal preparations should be checked for toxic chemical residues to allay consumer fears of exposure to known neuro-toxicant pesticides and to aid in promoting global acceptance of these products".
In China, the Traditional Chinese Medicine approach is used in formulating natural herbal teas and they are very popular in enhancing health and addressing core issues within the body; e.g. formulated recipes like hawthorn plus oolong / pu-er can address the high fat level in body's bloodstream. The Chinese term liang cha, means "cooling tea", and the Chinese drink it to cool down the body when it was overheated due to weather or sickness.
In Sri Lanka, herbal teas have a long history within the local tradition of indigenous medicine. Iramusu (Smilax regelii), Beli (Bael), Ranawara (Senna auriculata), Polpala (Aerva lanata), weniwel (Coscinium fenestratum), and kothala-himbutu (Salacia reticulata) are among the many plant species used to make herbal teas, which are used to treat a wide variety of ailments. The widely used "Paspanguwa" (translated as five-portions) is a common local remedy for colds and fever containing the five ingredients Pathpadagam (Mollugo cerviana), Katuwelbatu (Solanum virginianum), Koththamalli (Coriander seed), Thippili (Long pepper), and Inguru (Ginger), often served with a sweetener of sugar or Jaggery.
Herbal teas can be made with fresh or dried flowers, leaves, seeds or roots, generally by pouring boiling water over the plant parts and letting them steep for a few minutes. Seeds and roots can also be boiled on a stove. The herbal tea is then strained, sweetened if so desired, and served. Many companies produce herbal tea bags for such infusions.
While varieties of herbal teas are defined as any plant material for infusion, below is a list of common herbs:
Anise tea, made from either the seeds or the leaves.
Hibiscus (often blended with rose hip), a popular tea alternative in the Middle East which is drunk hot or cold. Hibiscus tea is also consumed in Okinawa, where the natives associate Hibiscus tea with longevity. See also Roselle below.)
Ho Yan Hor Herbal Tea, a recipe for herbal tea formulated by Malaysian Chinese
Hydrangea tea, dried leaves of hydrangeas; considerable care must be taken because most species contain a toxin. The "safe" hydrangeas belong to the Hydrangea serrata Amacha ("sweet tea") Cultivar Group.
Jiaogulan, (also known as xiancao or poor man's ginseng)
Kava root, from the South Pacific, is popular for its effects in promoting talkativeness and relaxation
Kratom, dried leaves of the Kratom tree, drank for its medicinal and stimulant effects
Kuzuyu, is a thick white Japanese tea made by adding kudzu flour to hot water
Labrador tea, made from the shrub by the same name, found in the northern part of North America.
Lapacho (also known as Taheebo) is the inner-lining of the bark (or cambium) of the Red or Purple Lapacho Tree which grows in the Brazilian jungles. It is boiled to make an infusion with many and varied health benefits.
Mate de coca (sometimes called "coca tea"), made from coca leaves. Authentic mate de coca contains very small amounts of cocaine and similar alkaloids. In some countries where coca is illegal, products marketed as "coca tea" are supposed to be decocainized, i.e., the pharmacologically active components have been removed from the leaf using the same chemicals used in manufacturing cocaine.
Mint, especially peppermint (also mixed with green tea to make mint tea)
Mountain Tea, a very popular tea in the Balkans and other areas of the Mediterranean region. Made from a variety of the Sideritis syriaca plant which grows in warm climates above 3,000 feet. Records of its use date back 2,000 years.
Roasted barley tea, known in Japanese as mugicha and Korean as bori cha. The roasted flavor can be reminiscent of coffee (without coffee's bitterness and caffeine). It is often drunk cold in the summer.
Rooibos (Red Bush) is a reddish plant used to make an infusion and grown in South Africa. In the US it is sometimes called red tea. It has many of the antioxidant characteristics of green tea, but because it does not come from tea leaves, it has no caffeine.
Ayurvedic tea is made of Ayurvedic herbs like Agya Ghas, Yeshtimadhu, Tulasi etc. Various pharmacies have come up with their products using different combinations of Ayurvedic medicines. Ayurvedic tea has also been found to contain nutrients including calcium, potassium, vanadium, iron, manganese, selenium and zinc.
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^Chan, E.W.C.; Lim, Y.Y.; Chong, K.L.; Tan, J.B.L.; Wong, S.K. (2010). "Antioxidant properties of tropical and temperate herbal teas". Journal of Food Composition and Analysis23 (2): 185–189. doi:10.1016/j.jfca.2009.10.002.
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