| Disease | TO BETTER UNDERSTAND THE BIOAVAILABILITHY OF TEA CATECHINS, 18 INDIVIDUALS WERE GIVEN DIFFERENT AMOUNTS OF GREEN TEA AN DMEASURED THE TIME-DEPENDENT PALSMA CONCENTRATIONS AND URINARY EXCRETION OF TEA CATECHINS. AFTER TAKING 1.5, 3.0, AND 4.5
GRAMS OF DECAFFEINATED GREEN TEA SOLIDS DISSOLVED IN 500 ML OF WATER, THE MAXIMUM PLASM CONCENTRATION VALUES (CMAX) WERE OBSERVED AT 1.4-2.4 HOURS AFTER INGESTION. CMAX RESULTS ERE 326 NG/ML FOR EGCG, 550 NG/ML FOR EGC, AND 190 NG/ML FOR EC.
WHEN THE DOSAGE WAS INCREASED FROM 1.5 TO 3.0 G, THE CMAX VALUES INCREASED 2.7-3.4 FOLD, BUT INCREASING THE DOSE TO 4.5 G DID NOT CHANGE THE CMAX VALUES SIGNIFICANTLY, INDICATING A SATURATION PHENOMENON. THE HALF-LIFE OF EGCG WAS APPROXIMATELY
5-5.5 HOURS, ALMOST TWICE THAT OF EGC OR EC 92.5-3.4 H). EGC AND EC, BUT NO EGCG, WER EXCRETED IN THE URINE, WITH OVER 90 PERCENT OF THE TOTAL URINARY EGC AND EC EXCRETED WITHIN EIGHT HOURS. ALTHOUGH THE AMOUNT OF EGC AND EC EXCRETION SEEMED
TO INCREASE WHEN THE TEA DOSAGE WAS INCREASED, A CLEAR DOSE-RESPONSE RELATIONSHIP WAS NOT OBSERVED. IT WAS ALSO DEMONSTRATED AND COCLUDED THAT CATECHINS FROM GREEN AND BLACK TEA ARE RAPIDLY ABSORBED AND THE ADDITION OF MILK DOES NOT IMPAIR
BIOAVAILABILITY OF TEA CATEHCINS. |