Black Tea
What is it? Overview Usage Side Effects and Warnings

What is Black Tea?

Black and green tea are made from the same plant, but black tea has been allowed to oxidize, altering its constituents. While green tea is high in catechins (especially epigallocatechin gallate, or EGCG), black tea contains relatively high levels of theaflavins, theanine, and thearubigens. Although green tea is more commonly presented as a healthful beverage, traditional black tea too might have health-promoting properties. However, there is no reliable evidence as yet for any of its proposed health benefits.

According to some but not all observational studies , high consumption of black tea is associated with reduced risk of heart disease and heart disease death. 1 2 Unfortunately, observational studies are notoriously unreliable for proving the efficacy of a treatment. Some additional support comes from animal studies that hint black tea may help prevent atherosclerosis , the primary cause of heart disease. 3 However, only double-blind , placebo-controlled studies can actually prove a treatment effective, and few have been conducted on black tea. (For information about why such studies are essential, see Why Does This Database Rely on Double-blind Studies? ) One double-blind, placebo-controlled study found that black tea modestly improves cholesterol profile, but it enrolled too...

Safety Issues

As an extraordinarily widely consumed beverage, black tea is presumed to have a high safety factor. Its side effects would be expected to be similar to those of coffee—heartburn, gastritis, insomnia, anxiety, and heart arrhythmias (benign palpitations or more serious disturbances of heart rhythm). 4 All drug interactions that can occur with caffeine would be expected to occur with black tea.

Interactions You Should Know About

If you are taking:

  • MAO inhibitors : The caffeine in black tea could cause dangerous drug interactions.
  • Stimulant drugs such as Ritalin: The stimulant effects of black tea might be amplified.
  • Drugs to prevent heart arrhythmias or to treat insomnia , heartburn , ulcers , or anxiety : Black tea might interfere with their action. ...