Cancer Prevention and Tea?
Tea drinking is an ancient tradition dating back 5,000 years in
China and India. Long regarded in those cultures as an aid to good health, researchers
now are studying tea for possible use in the prevention and treatment of
a variety of cancers. Investigators are especially interested in the antioxidants
called catechins found in tea. Despite promising early research
in the laboratory,
however, studies involving humans so far have been inconclusive.
1. What are antioxidants?
The human body constantly
produces unstable molecules called oxidants, also commonly referred to as free
radicals. To become stable, oxidants steal electrons from other molecules and,
in the process, damage cell proteins and
genetic material. This damage may leave the cell vulnerable to cancer.
Antioxidants are substances that allow the human body to scavenge and seize
oxidants. Like other antioxidants, the catechins found in tea selectively
inhibit specific enzyme activities that lead to cancer. They may also target and
repair DNA aberrations caused by oxidants.
2. What is the level of antioxidants found in tea?
All varieties of tea come from the leaves of a single evergreen plant, Camellia
sinensis. All tea leaves are picked, rolled, dried, and heated. With the
additional process of allowing the leaves to ferment and oxidize, black tea is
produced. Possibly because it is less processed, green tea contains higher
levels of antioxidants than black tea.