9 Health Benefits of Drinking Tea

160 million Americans drink tea daily. That’s a large number of tea-drinkers. According to statistics, tea is the second most-consumed beverage after water. According to the Tea Association of the USA, the annual sales of tea from stores across the nation have risen well above $2.2 billion. Why are more people drinking tea these days? There is supporting data from medical research to show that there are many health benefits of drinking tea.

The origin of tea is the leaves of Camellia Sinensis, an evergreen tree with an average height of 16m. White tea, green tea, oolong, pu-erh tea, and black tea are all obtained from this plant, although they are processed using different means to get to varying levels of oxidation. Green tea is made from steaming and drying the leaves of Camellia Sinensis. White tea is made from withering, rolling, fermenting, and lastly drying the leaves. It is harvested when the buds are still covered with white hair (before they get ripened), hence the name. Black tea is made by rolling up the leaves 90-120 minutes before they dry so that they can undergo oxidation. Oolong tea has a shorter fermentation period than black tea.

9 Health Benefits of Drinking Tea

1. Decreases the risk of hypertension: In 2004, a study of 600 individuals in the Chinese population, of which 39.8% were habitual tea drinkers (green or oolong tea), showed that the risk of developing hypertension was decreased by 46% for those who usually drank between 120-599mL per day, and also decreased by 60% for those who drank 600mL or more per day.
2. Decreases blood pressure and prevents atherosclerosis: Atherosclerosis is the blockage of blood vessels due to the accumulation of substances in a region, leading to impaired vasodilation. A study of black tea consumption showed that it increases the endothelium-dependent flow mediated dilation (FMD) and decreases both the systolic and diastolic blood pressure. Flavanols, compounds present in black tea, were found to be responsible for these benefits.
3. Decreases Cardiovascular Disease: Studies show that drinking three or more cups of tea daily results in an 11% reduction in the occurrence of myocardial infarction and a 21% reduced risk of ischemic stroke.
4. Decreases Osteoporosis: Research performed on animals shows that green tea has bioactive components that decrease osteoporosis. The chemicals in green tea responsible for this health benefit are polyphenols. More research still needs to be done to show application in the human population.
5. Low Diabetes Prevalence: Epidemiological studies using data-mining techniques show that there is a linear correlation between high black tea consumption and low diabetes prevalence. The data used in this study was obtained from 50 participating countries.
6. Antioxidant property: Black or green tea have antioxidant properties.
7. Antiviral property: Recently, the FDA approved an extract of green tea leaves, Sinecatechins, for the treatment of external genital and perianal warts.
8. Anti-cancer activity: Epidemiological data (not clinical trials data) shows that green tea is associated with decreased cancer risk.
9. Weight loss: Drinking tea is associated with weight loss and is a healthy way to go on a diet without any associated health risks.

References:
1. Duke JA. Camellia Sinensis (L.) Kuntze. Handbook of Energy Crops [Internet]. 1996 Jul 3. Available from: http://www.hort.purdue.edu/newcrop/duke_energy/camellia_sinensis.html
2. Yang YC, Lu FH, Wu JS, Wu CH, Chang CJ. The Protective Effect of Habitual Tea Consumption on Hypertension. Archives of Internal Medicine [Internet]. 2004 Jul 26; 164(14):1534-40. Available from: http://www.ncbi.nlm.nih.gov/pubmed/15277285
3. Grassi D, Draijer R, Desideri G, Mulder T, Ferri C. Effects of Black Tea With and Without a Fat Load on Vascular Function in Mildly Hypertensive Volunteers. Available from: http://www.teausa.com/teausa/images/Speaker%20Abstracts.pdf
4. Chen C, PhD, CCRP. Green Tea and Bone Health: From Bench to Clinical Trial. Available from: http://www.teausa.com/teausa/images/Speaker%20Abstracts.pdf
5. Beresniak A, Duru G, Berger G, Bremond-Gignac D. Relationships Between Black Tea Consumption and Key Health Indicators in the World: An Ecological Study. BMJ Open [Internet]. 2012; 2(6):e000648 doi:10. Available from: http://www.bmjopen.bmj.com/content/2/6/e000648.full
6. Peters U, et al. Does Tea Affect Cardiovascular Disease? A Meta-Analysis. Am J Epid. 2001;154(6):495-503.
7. Arab L, et al. Green and Black Tea Consumption and Risk of Stroke: A Meta-Analysis. Stroke. 2009;40(5):1786-1792.