Consuming green tea may reduce the risk for disabilities in old age, according to a new study.
Green tea is made from the leaves of Camellia sinensis, an evergreen shrub native to Southeast Asia. Both green tea and black tea are made from the same plant species. Green tea is produced by lightly steaming the leaves. Black tea is produced by allowing the leaves to ferment. Preliminary studies have investigated the effect of tea on memory and awareness. Additional research is need before a conclusion can be made.
In a new study, researchers analyzed data on 13,988 elderly Japanese individuals to assess the potential relationship between green tea consumption and disabilities. Information on lifestyle and green tea intake were collected through questionnaires, and disability information was gathered through a public database on long-term care insurance.
The researchers found that when compared to individuals who consumed less than one cup of green tea daily, green tea consumption was linked to a significantly reduced risk for disabilities. The authors reported a 10 percent, 25 percent and 33 percent reduced risk for individuals who consumed 1-2 cups, 3-4 cups and 5 or more cups of green tea daily, respectively.
Although these early results are promising, this study only suggests a potential association and does not prove a cause-and-effect relationship. Additional research is needed before a firm conclusion can be made.
Green tea is rich in the class of polyphenol compounds known as catechins. Polyphenols may have health benefits for humans. Many of the effects of green tea are thought to be due to its most abundant catechin, epigallocatechin gallate (EGCG). Traditional health claims for green tea include improved urine flow, relief of joint pain and improved resistance to diseases. Historically, green tea bags have been applied to the body to soothe sunburn, headache and tired eyes. Green tea is an accepted cancer prevention treatment in Japan and Fiji.
Other integrative therapies that have been studied for their potential benefits in longevity and aging include ashwagandha, resveratrol and selenium. The use of ashwagandha as an anti-aging agent is based on traditional use in Indian Ayurvedic medicine to promote physical and mental health, improve resistance to disease and promote longevity. Human research is lacking in this area, and currently there is insufficient evidence to draw a firm conclusion.
Resveratrol has been included in herbal products that are marketed to increase lifespan and prevent aging. Limited evidence shows a possible benefit for this use, but further research is necessary.
Because antioxidant supplements are thought to slow aging and prevent disease, it has been proposed that selenium supplementation may help people live longer. However, results from clinical trials are mixed, and it is still unclear whether selenium supplementation can increase lifespan in healthy individuals.
For more information about integrative therapies that have been studied for longevity and aging, please visit Natural Standard's Comparative Effectiveness Database.
For more information about green tea, please visit Natural Standard's Foods, Herbs & Supplements Database.
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