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Tea and Your Health
As if the huge variety of exquisite, sensory pleasures that fine tea affords us werent enough, the medical community continues to shower praise in the form of reports about the positive effects tea has on health and well being. As you continue reading you will find a brief summary of the more substantiated accounts. Many of the studies were conducted in Japan and China, predominantly green tea-drinking countries, and are therefore based on green tea. Currently there are, however, countless research programs being run in Europe and America to examine the benefits of black tea - so we can expect new results in the near future.
To understand the health benefits of tea, we must look at the properties of teas that are most frequently referred to in the reports:
Polyphenols - the primary biological active ingredients of (green) tea are powerful antioxidants (catechins). Antioxidants counteract free radicals in the body, which are thought to contribute to cancer.
Essential Oils - they develop during the production process from the active substances in the leaves and give tea much of its aroma and fragrance.
Vitamins and Nutrients - Vitamin C makes an impressive appearance in green teas. It is stated that 2 small cups of green tea have as much Vitamin C as a large glass of orange juice. Tea is also a good source of manganese, potassium, niacin, folic acid and trace amounts of Vitamins B1, B2 and K.
Summary of Health Benefits of Tea
Cancer - Laboratory studies have shown that the antioxidant properties of tea have an effect against cancer by inhibiting formation of cancer causing substances. This is one of the most important and widely studied areas of the health benefits of tea.
Immunity - Polyphenols have been shown to help increase the white blood cell count which is responsible for fighting infection. The high vitamin C content found in green tea also contributes, as it is a well studied and accepted use in helping prevent and fight colds.
Cardiovascular - Cardiovascular research suggests that a diet rich in the antioxidants found in tea, is able to prevent heart disease and stroke. The tea constituents have been shown to stimulate the circulatory system, to strengthen the blood vessels and to decrease the cholesterol level in the blood stream.
Digestion - Essential oils and polyphenols aid digestion by increasing the flow of digestive juices. Drinking tea during or after a high-cholesterol meal has been shown to lower the increase in the fat content of the blood.
Body Weight - There are indications that certain teas such as Pu-Erh can assist in reducing weight by having an effect on the fats in the blood stream and in the tissues.
Teeth and Bones - Many dentists recommend drinking tea because it is rich in fluorides, a mineral that strengthens both tooth enamel and bones in a fight against osteoporosis. The Polyphenols in tea were shown to affect the bacteria in the mouth, thereby reducing the formation of plaque.
Germicide & Antibacterial - Some studies indicate that tea acts as a mild germicide. In the digestive tract it helps fight food poisoning and diseases like cholera, typhoid, and dysentery. (Did you say that you were going to Bangladesh this year?). Its antibacterial properties help to inhibit certain throat infections. In China, green tea is being used as a home remedy to disinfect cuts and abrasions and to cure or prevent skin disease and athletes foot.
Mental Activity - Tests have shown that tea drinking improves concentration, alertness and problem-solving ability.
Longevity - The sum of the curative and preventive health benefits of tea tends to indicate a healthier and longer life. Research continues to work at finding more evidence by studying the different tea drinking cultures.
Health Benefits by Tea type
Black Tea - Since more research is done on green tea in regard to health benefits,
it is easy to believe that green is the only tea worth drinking. This simply is not true! Like green and white tea, black
tea is a powerful source of anti-oxidants that slow down the aging process and prevent a wide variety of diseases. It has
antiviral and anti-inflammatory properties, providing protection against tooth decay and infection as well as relief from
arthritis.
Though some of the most important anti-oxidants in the tea plant are compromised during the black tea fermentation process,
studies show that black tea still provides an abundance of antioxidant activity. Among the most important anti-oxidants
in the tea plant, those known as theaflavins remain intact even after fermentation. Theaflavins in black tea have been
shown to scavenge abnormal cells, helping to rid them from the body before they can do damage or mutate into cancer cells.
Theaflavins have also been shown to have the power to inhibit oxidation, in particular the oxidation of LDL cholesterol,
giving black tea the potential to significantly reduce blood cholesterol and thereby reduce the risk of cardio vascular
disease.
Drinking tea on a regular basis may even help patients who have existing cardiovascular disease, according to a study in
one issue of Circulation: Journal of the American Heart Association, which finds that tea consumption is associated with
an increased rate of survival following a heart attack.
Yet another study in Germany found that drinking black tea significantly improved the ability of arteries to relax and
expand to maintain healthy blood pressure. They showed molecules in the tea called catechins helped dilate the blood vessels
by producing a chemical called nitric oxide.
So, as you can see, green tea isn’t the only tea
that is good for you. Drinking black tea can also be a very healthy and welcome
addition to your diet. And, that’s good news since 80% of the tea consumed in
the world is black tea!
Oolong Tea - Traditionally enjoyed with meals, oolong assists digestion
by neutralizing excess acidity and preventing fermentation in the stomach. It also breaks down fat molecules into
smaller particles, making them much easier to digest. Drinking oolong tea during or after a high-cholesterol meal
has been shown to lower the intake of fat content in the blood. Its ability to increase metabolism as well as burn
fat explains oolong tea’s wide appeal as a weight loss aid.
Oolong contains significant amounts of vitamins A, C, and E, as well as essential minerals and trace elements.
Because it is rich in antioxidants, oolong tea promotes healthy teeth, skin and bones and can help to lower
cholesterol and protect against heart disease. Studies have shown that oolong removes cholesterol deposits and
other sticky plaque from the walls of the blood vessels, thereby playing a role in preventing arteriosclerosis,
heart disease, and strokes.
Oolong tea contains a significant quantity of polyphenol, commonly known as tannin, which scientists believe
may account for the lower risk of cancer in tea drinkers because of its ability to help DNA cells to accurately
reproduce. Since the polyphenols and other antioxidants contained in oolong help to suppress tumor formation,
drinking this tea daily provides strong protection against the development of all types of cancer.
Relatively low in caffeine, oolong has mild stimulating effects on the central nervous system, enhancing alertness,
improving cerebral functions, and relieving mental fatigue. In addition, the tea's mild diuretic properties promote
swift elimination of the toxins and acid wastes flushed from the blood and tissues by the antioxidant and alkaline
elements in the tea.
Green Tea - Through the ages, green tea has been regularly consumed in
India, China, Japan, and Thailand. In traditional Chinese and Indian medicine,
practitioners have used green tea as a stimulant, diuretic and astringent (to
control bleeding and help heal wounds), and to improve heart health. Other
traditional uses of green tea include regulating blood sugar, promoting
digestion, and improving mental performance.
Over the last few decades green tea has been the subject of many scientific and medical
studies to determine the extent of its long-purported health benefits. Early
evidence suggests that regular green tea drinkers may have lower risk of heart
disease, specifically heart attack or atherosclerosis by preventing the oxidation of LDL Cholesterol,
which can consequently reduce the buildup of plaque in arteries.
Green tea contains many antioxidants, including those known as flavonoids that can protect against
free radical damage to the brain. Research indicates green tea could be beneficial in reducing inflammation related to
arthritis and slowing cartilage breakdown as well as improve bone mineral
density in older women. Green tea may help regulate glucose in the body
as well as boost metabolism and help burn fat.
Catechins are the major group of polyphenols in green tea, the most important of
which seems to be epigallocatechin-3-gallate (EGCG). EGCG helps suppress inflammation and has been widely
studied for its reported protection against certain cancers.
White Tea - White tea has a broad range
of positive effects on the body and a tremendous number of health benefits. Its
supreme power is in preventing disease and disorder. Being the least
processed of all the teas, white tea is loaded with antioxidants. Antioxidants
are protective nutrients that have the ability to neutralize free radicals that
would otherwise wreak havoc on your body, damaging DNA and accelerating aging.
Studies show that antioxidants offer protection
against cancer, heart disease and stroke, as well as numerous other conditions.
White tea strengthens bones and teeth as well as the circulatory and immune
systems, easing the symptoms of illness and promoting recovery. It has also
been proven that ingredients in white tea are effective in boosting the immune
function of skin cells and protecting them from the damaging effects of the sun,
an important finding in the fight against skin cancer.
Rooibos - Rooibos has been known for centuries in South Africa for
its unique medicinal properties - from soothing upset stomachs and aiding with
digestion, calming nervous tension and lowering blood pressure, to providing
relief from allergies such as eczema. The many health benefits of this unique
beverage are just beginning to be validated and appreciated. An herbal infusion
rather than an actual tea, rooibos has many of the benefits of Camellia
Sinensis without the caffeine.
Like green and white tea, rooibos tea is an excellent
source of antioxidants, which appear to reduce the risk of certain chronic
diseases including cancer. It is also packed with health-boosting polyphenols
and contains a unique antioxidant called aspalathin, which counteracts the
atherosclerotic processes that result in heart disease. Rooibos is a rich
source of flavonoids, which in addition to their antioxidant capabilities have
antiviral and anti-tumor properties.
Furthermore, Rooibos is popular among athletes,
as it is a rich source of depleted minerals after a workout. Three grams of
Rooibos in 8-ounces of water contain: 1.09 mg of calcium, 0.22 mg of fluoride,
0.07 mg of iron, 1.67 mg of manganese, 7.12 mg of potassium, 6.16 mg of sodium
and 0.04 mg of zinc. Rooibos is also very low in tannins, which are said to
inhibit the absorption of protein and iron.
Besides having none of the negative effects of
caffeine, rooibos is even thought to have a soothing effect on the nervous
system. Some people report that drinking a cup prior to bedtime helps with
insomnia. Rooibos tea is believed to have anti-aging properties and recent
studies point to its potential in protecting against age related damage to the
brain. An unpublished study by the Institute for Medical Science of Aging at
the Aichi Medical University in Japan called Rooibos the "Anti-Aging
Beverage" (see pg. 35, Tea Almanac 2001 Fresh Cup Magazine). The
anti-aging properties are said to stem predominantly from Rooibos’ ability to
remove free radicals.
Rooibos is completely safe for pregnant and
breastfeeding women, as well as young children. Researchers know of no adverse
side effects associated with the use of rooibos tea, so it can be drunk
regularly and freely. You could say that this is one case where more is better!
To a long and healthy life!
Please note: We only present these findings from researchers and institutions. We are surrounded here by tea pots and tasting cups, not test tubes and petri dishes. And while researchers work toward resolutions, we will simply continue to enjoy all the pleasures fine tea offers us.
Additional Resources
"Ancient Chinese White Tea May Fight Obesity"
(Telegraph.co.uk, 2009)
"Green Tea Overview" (Univ. of Maryland, 2007)
"Health Benefits of Green Tea" (WebMD, May 2009)
"Put the kettle on: Tea is steeped in health benefits"
(USAToday.com, 2007)
"An Overview of Research on the Potential Health Benefits of Tea" (teausa.com)
"Doctors Discover Lapacho"
(CureZone.com, 2005)
"The Proof is in:
Drinking Tea is Healthy"
(Harvard
Health Publications, 2005)
"Green Tea May Fight Alzheimer's"
(MSN.com, Health, Reuters, Sept. 20 2005)
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