Black Tea may Curb Heart, Diabetes Risks

[Guest guest]

Black Tea may Curb Heart, Diabetes Risks

Evidence review suggests that three cups daily may reduce the risk of

cardiovascular disease and diabetes

by Craig Weatherby

http://newsletter.vitalchoice.com/e_article002331367.cfm?x=bkyWfwl,bhfgs9lc

----------

Fortunately for those who favor and savor it, there’s evidence that drinking

lots of tea – green or black, with differences between the two types – may

reduce the risk of cardiovascular disease, stroke, and diabetes.

For more on that subject, see “Green Tea May Cut Risk of Heart Disease and

Cancer”, “Caffeine May Curb Diabetes”, and “Tea and Chocolate May Deter Strokes,

Brain Damage” and related articles from the Cocoa, Tea & Coffee section of our

news archive.

Now there’s more reason to believe that drinking black tea may reduce the risk

of cardiovascular disease and diabetes (Ruxton CH, Mason P 2011).

The British authors of a new evidence review examined 40 epidemiological

(statistical) studies to look for evidence linking black tea with the risk of

cardiovascular disease (CVD) and diabetes.

Their analysis of that evidence suggest that drinking three or more cups per day

reduces the risk of coronary heart disease.

Specifically, people who reported drinking the most tea were 30-57 percent less

likely to develop CVD, versus those drinking little or no tea.

And the results suggest a lesser but significant risk-reduction benefit for

diabetes at four cups daily.

Why would black tea help hearts and deter diabetes?

Lead author Ruxton, Ph.D., linked the lower CVD risk found among black

tea drinkers to several factors, including reduced arterial stiffness and

inflammation.

As she said, “… these beneficial findings are thought to be due to positive

factors in black tea such as flavonoids and theanine, which may help to control

blood pressure by regulating nitric oxide production and inhibiting platelet

aggregation.” (TAP 2012)

Dr. Ruxton noted the interesting results of a prior laboratory study that

compared the effects of black and green tea on nitric oxide production and

dilation of the blood vessels. (Nitric oxide relaxes and widens arteries, which

generally enhances cardiovascular health.)

Both types of tea stimulated production of nitric oxide and relaxation of the

aorta, the large artery through which blood leaves the heart.

And as she said, this earlier study showed that black tea possesses some

advantages over green tea:

“The only ingredient in green tea to cause nitric oxide production and

relaxation of the arteries was epigallocatechin-3-gallate (EGCG). However,

ingredients in black tea – the theaflavins and thearubigins, which are produced

during fermentation of green tea to make black tea – were far more potent than

EGCG in stimulating nitric oxide production and relaxation of the aorta.” (TAP

2012)

It's not that black or green tea is clearly better than the other for

cardiovascular or immune health. But neither is one kind clearly superior for

all respects of human health.

Vive la difference!

Sources

• Arab L, Liu W, Elashoff D. Green and black tea consumption and risk of

stroke: a meta-analysis. Stroke. 2009 May;40(5):1786-92. Epub 2009 Feb 19.

Review.

• Debette et al. Tea consumption is inversely associated with carotid plaques

in women. Arteriosclerosis, Thrombosis and Vascular Biology 2008;28:353-9.

• Gardner EJ, Ruxton CH, Leeds AR. Black tea--helpful or harmful? A review of

the evidence. Eur J Clin Nutr. 2007 Jan;61(1):3-18. Epub 2006 Jul 19. Review.

• Hamer M, Witte DR, Mosdøl A, Marmot MG, Brunner EJ. Prospective study of

coffee and tea consumption in relation to risk of type 2 diabetes mellitus among

men and women: the Whitehall II study. Br J Nutr. 2008 Nov;100(5):1046-53. Epub

2008 Mar 4.

• Iso H, Date C, Wakai K, Fukui M, Tamakoshi A; JACC Study Group. The

relationship between green tea and total caffeine intake and risk for

self-reported type 2 diabetes among Japanese adults. Ann Intern Med. 2006 Apr

18;144(8):554-62.

• Langley- SC. Consumption of black tea elicits an increase in plasma

antioxidant potential in humans. Int J Food Sci Nutr. 2000 Sep;51(5):309-15.

• Lorenz M et al. Green and black tea are equally potent stimuli of NO

production and vasodilatation: new insights into tea ingredients involved. Basic

Res Cardiol 2009; 104:100-110.

• Mukamal M et al. Tea consumption and mortality after acute myocardial

infarction. Circulation 2002;105:2476-2481; Yockum L et al. Dietary flavonoid

intake and risk of cardiovascular disease in postmenopausal women. Am J

Epidemiol 1999;149:943-9.

• Ruxton CH, Mason P. Is black tea consumption associated with a lower risk of

cardiovascular disease and type 2 diabetes? Nutrition Communications. 22 Dec

2011. Accessed at

http://onlinelibrary.wiley.com/doi/10.1111/j.1467-3010.2011.01937.x/abstract

• Sesso HD, Paffenbarger RS Jr, Oguma Y, Lee IM. Lack of association between

tea and cardiovascular disease in college alumni. Int J Epidemiol. 2003

Aug;32(4):527-33.

• The Tea Advisory Panel (TAP). New insights into black tea ingredients

involved in protection against cardiovascular disease. Accessed January 23, 2012

at http://www.teaadvisorypanel.com/files/bulletins/chronicdisease.doc

• van Dam RM, Willett WC, Manson JE, Hu FB. Coffee, caffeine, and risk of type

2 diabetes: a prospective cohort study in younger and middle-aged U.S. women.

Diabetes Care. 2006 Feb;29(2):398-403.

• van Dieren S, Uiterwaal CS, van der Schouw YT, van der A DL, Boer JM,

Spijkerman A, Grobbee DE, Beulens JW. Coffee and tea consumption and risk of

type 2 diabetes. Diabetologia. 2009 Dec;52(12):2561-9. Epub 2009 Sep 1.