Friday, November 10, 2006

Black Tea and Health


As you may have noticed, we did not send out an October edition of the tea newsletter. Busy upgrading the web site, we are pleased to unveil our new look with many added features and even easier navigation. Look for an upcoming e-mail inviting you to write online tea reviews for product discounts, another new feature of the web site.


In September, we looked at a published review of tea research conducted at Kings College in the UK. Of the numerous studies examined we selected hydration and caffeine as it relates to tea consumption. Those findings revealed that tea hydrates the body as effectively as water with added benefits despite the popular misconception that the caffeine content in tea is dehydrating.


To set the stage, reviewers took an in-depth look at epidemiological and clinical studies relevant to tea from 1990 - 2004; the various research methodologies utilized in the studies and the way in which the results were reported. The review's objective was to determine if consuming black tea has a positive or negative impact on health. Based on that, a strict criteria was created excluding vague studies making the review's results relevant. Important to note is the review's title "Black Tea - Harmful or Helpful?"


Here are some basic black tea facts - black teas;

  • Contain on average 200 mg of flavonoids per cup.
  • Represent 78% of the tea produced worldwide.
  • Is the most commonly consumed in Western populations.
  • Undergo oxidation in manufacture.

Reviewers determined that the beneficial properties in green teas, primarily EGCG polyphenols, are easier to identify than the flavonoid polyphenols in black teas, thearubigins and theaflavins. Polyphenols are components of the tea plant and the primary source of the health benefits in tea. Polyphenols undergo changes during the processing of the leaves. These changes result in the difference between black and green teas polyphenols and subsequent benefits.

  • Black teas contain more complex flavonoids then green teas; specifically thearubigins and theaflavins.
  • Thearubigins and theaflavins are powerful antioxidants.
  • Flavonoids, because of their complexity, do not absorb as quickly in the body and initially can be harder to identify.
  • Green teas differ from black teas because they are non-oxidized during manufacture/processing.

The review concluded;
  • Drinking three cups of black tea per day for two weeks increased the concentration of flavonoids in the blood by 25%.
  • The consumption of flavonoids can lower the risk of coronary heart disease through a number of mechanisms.
  • Tea flavonoids have also been shown to reduce low-density lipoprotein (LDL) cholesterol by 11.1%.
  • In-vitro and animal studies reveal positive effects of flavonoids go beyond antioxidant capacity, stimulating anti-inflammatory response, another cause of disease.

The always controversial question, "does adding milk to your tea reduce the benefits?" was also part of the review. After examining four separate studies, reviewers concluded that the addition of milk in your tea is unlikely to reduce the antioxidant benefits, despite milks binding effects to flavonoids.


This review makes it clear that tea is good for your health and that black teas complex flavonoid polyohenols can play an important role in daily antioxidant consumption and disease prevention. While green teas continue to steal the "health limelight," black teas belong center stage right along side them. I am a firm believer in drinking the type of tea you like. If that's black tea, you haven't been left behind in the rush to achieve a healthy lifestyle, black tea is good for you too!