Tea Research Association (TRA), Tocklai
in collaboration with
Indian Institute of Chemical Biology (IICB), Kolkata has carried out
studies on health aspects of black tea. In these studies, the influence of tea
in totality was examined rather than evaluating isolated fractions. Results
indicated the following:
-
Regular administration of low dose of black tea extracts (0.002-0.2%)
significantly reduced the total cholesterol levels in rats.
-
Normal rates of black tea extracts significantly reduced the trigycerides
levels.
-
The level of HDL (high density lipids) was increased though not significantly.
-
The levels of VLDL (very high density lipids) and LDL (low density lipids)
showed a slight decrease but the effect was not significant.
Thus the results indicated that chronic
administration of black tea is capable of reducing the total cholesterol and
triglyceride levels in healthy animals. The flavonoids in tea prevent oxidation
of LDL cholesterol.
In another study effect of black tea
consumption on diabetes mellitus was evaluated. Consumption of black and green
tea could not only prevent the experimentally induced diabetes but was also
found to be effective in curing diabetes induced by streptozotocin in rats.
The effect of black tea consumption on
liver function was examined by monitoring the levels of SGOT (serum glutamic
oxolacetic transaminase) and SGPT (serum glutamic pyruvic transaminase) in
experimental hepatoxicity induced rats. Results indicated that consumption of
black or green tea had no adverse effect on liver function in the experimental
animals.
The influence of tea on muscular function
was studied by examining the effect of hot water brew of black or green tea on
the mammalian skeletomotor apparatus. Black tea extract produced a
concentration dependent facilitation of muscle contraction induced by nerve
stimulation.
The effect of tea consumption on
experimentally induced gastric ulcer in rats was also carried out. Tea extracts
was most effective in preventing ulcers induced by aspirin, indomethacine, cold
resistant stress and reserpine.
Further studies on health aspects of tea
are in progress.
Principal Components of Black Tea Beverage
|
