White, Green and Black Tea: Which is most beneficial?

Tara Raven 2009

Tea:
Camellia sinensis



    All ‘true tea’ comes from one evergreen plant called Camellia sinensis, which is grown in various temperate climates around the world. Tea plants are native to Southeast Asia, and have been planted widely in tropical and subtropical areas. Some species can tolerate light frost. Camellia sinensis is a small evergreen tree with a strong taproot, growing to around 6 to 8 feet tall, most often pruned back to shrubs in tea cultivation. Seedlings are usually shaded until they are 6 to 12 months old. They can typically tolerate varying moisture conditions, including drought. (Pratt 2004)
Four types of tea are produced from the same bush: white, green, black, and oolong. The differences in these four teas are, in the way and time of which the leaves are harvested. (Pratt 2004) The white tea leaves are harvested when the leaves are new, still rolled up with white hairs and not fermented at all. Green tea leaves are harvested, as young leaves and dried. Black tea is the mature leaves, which are then fermented. Black tea is the most popular tea around the world; there are over 3000 varieties of black tea. Oolong tea is black tea that is fermented then smoked. (Ng 2008) Each ‘kind’ of Camellia sinensis tea has its own exceptional health benefits and is most known for its antioxidant properties. (Packer 1999) 
    Green tea and Black tea contain certain antioxidants known as polyphenols (catechins), which appear to prevent cancer cells from dividing like, epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Black tea fermentation causes simple polyphenols to undergo polymerization, which produces complex molecules called theaflavins (99 times more potent than green tea) and therarubigens (45 times more potent than green tea). (Mills 2007) Polyphenols are anti-inflammatory, antibacterial, and antitumor. Polyphenols also prevent the oxidation of LDL cholesterol, which can cause artery plaque. Polyphenols enhance the whole antioxidant network by helping Vitamin C regenerate. (Packer 1999) White tea has three times the amount of antioxidants as green tea because of its tender age at harvest. White tea contains less caffeine than green or black tea, about 15 mg per serving. (Pratt 2004)
    Green tea is inversely associated with cognitive impairment. (Abrahams  2007)Past cell culture and animal studies have found that green tea may protect the brain against degenerative processes leading to Alzheimer’s and Parkinson’s because green tea constituents can inhibit the buildup of amyloid proteins associated with Alzheimer’s and Parkinson’s. (Kuriyama 2006)
In a study conducted by, Mauro Serafini at the National Institute Of nutrition in Rome, tests revealed that antioxidant activity in the tea drinkers blood rose 41 to 48 percent within thirty minutes of drinking green tea and within fifty minutes after consuming black tea. The antioxidant levels returned to normal after eighty minutes. (Carper 1996)
    Black tea consumption encourages the enzyme detoxification system in the liver, (Mills 2007) helping rid the body of free radicals and foreign chemicals that have the ability to alter and destroy cells. According to Robert Nicolosi, professor of clinical sciences and tea researcher at the University of Massachusetts: black tea helps dissolve and prevent blood clots, and may be as strong as vitamin E at preventing oxidative changes and stress in LDL cholesterol. (Carper 1996)
Human experiments using oral doses of green and black tea extracts have shown that:
   ÿ    Green and black tea cause a significant increase in the antioxidant activity of plasma;
   ÿ    Green tea s 50% stronger than black tea in vivo;
   ÿ    The effect is rapid;
   ÿ    Adding milk destroys the antioxidant activity by causing the protein binding which inhibits its decomposition. (Mills 2007)
Consuming a combination of white, green and black tea would be an appropriate protocol when considering tea as preventative health measure. (Kuriyama 2006)  Green and black tea have similar, distinct and, in some cases overlapping biochemical, physiological, and epidemiological effects. Tea offers powerful protection against many cancers, slows tumor growth, it also has the ability to stabilize blood lipids, making it a valuable part of an overall health care regimen. (Abrahams  2007) People who are sensitive to, or cautioned to reduce or avoid, caffeine, can still use the decaffeinated form of green tea, which is still shown to have some of the same medicinal properties and qualities. (Pratt 2004) Always consult your physician for contraindications of caffeine and medications.

References:



Abrahams, P., (2007). How the Body Works. London, UK: Bright Star Publi-
    shing.


Carper, J. (1996). Stop Aging Now. The Ultimate Plan For Staying Young and
     Preserving the Aging Process. New York, N.Y.: Harper-Collins.

Kuriyama S, Hozawa A, Ohmori K, Shimazu T, Matsui T, Ebihara S, Awata S,
 Nagatomi R, Arai H, Tsuji I.(2006) Green tea consumption and cognitive
 function: a cross-sectional study from the Tsurugaya Project 1. American  Journal of Clinical Nutrition. pp. 355-61.

Mills, S. & Bone, K. (2007). Principles and Practices of Phytotherapy: Modern
 Herbal Medicine. London, UK.: Churchill Livingstone.


Ng, T., Feng, L., Niti, M., Kua, E., Yap, K. (2008). Tea Consumption and
Cognitive Impairment and Decline in older Chinese Adults. American
Journal of Clinical Nutrition, pp.224-231.

Packer, L., Colman, C. (1999) The Antioxidant Miracle. New York, N.Y.:
    John Wiley & Sons, Inc.

Pratt, S., & Matthews, K. (2004). Super Foods. New York, N.Y.: Harper-
Collins.