| Disease | IN THE FIRST STUDY, THE ACUTE EFFECTS OF FOUR HOT DRINKS - GREEN TEA AND BLACK TEA(AT A DOSE EQUIVALENT TO 4 STANDARD CUPS), WATER MATCHED TO THE TEAS FOR CAFFEINE CONTENT('CAFFEINE') AND WATER - WERE ASSESSED IN 20 NORMOTENSIVE MEN USING A
LATIN-SQUARE DESIGNED STUDY. CLINIC BLOOD PRESSURE WAS MEASURED BEFORE AND 30 AND 60 MIN AFTER EACH DRINK HAD BEEN INGESTED. IN THE SECOND STUDY, THE EFFECTS ON BLOOD PRESSURE OF REGULAR GREEN AND BLACK TEA INGESTION WERE EXAMINED IN 13 SUBJECTS
WITH HIGH-NORMAL SYSTOLIC BLOOD PRESSURE AND MILD SYSTOLIC HYPERTENSION (SYSTOLIC BLOOD PRESSURE IN THE RANGE 130-150 MMHG) USING A 3-PERIOD CROSSOVER STUDY. 5 CUPS PER DAY OF GREEN TEA, BLACK TEA AND CAFFEINE (IN HOT WATER AND MATCHED THE TEAS)
WERE CONSUMED FOR 7 DAYS EACH, IN RANDOM ORDER. 24 HOUR AMBULATORY BLOOD PRESSURE WAS MEASURED AT THE END OF EACH 7 DAY INTERVENTION. RESULTS ARE PRESENTED AS MEANS AND 95% CONFIDENCE INTERVALS (CI). RESULTS AND ACUTE PRESSOR RESPONSE TO
CAFFEINE WAS OBSERVED. RELATIVE TO CAFFEINE, THERE WERE FURTHER ACUTE INCREASES IN SYSTOLIC AND DIASTOLIC BLOOD PRESSURE AT 30 MIN AMONG THOSE DRINKING GREEN TEA[5.5 MMHG(95%CI-1.4 TO 12.4) AND 3.1 MMHG(95%CI-0.1 TO 6.3), RESPECTIVELY] AND BLACK
TEA[10.7 MMHG(95% CI 4.0 TO 17.4) AND 5.1 MMHG(95% CI 1.8 TO 8.4), RESPECTIVELY]. THE CHANGES IN BLOOD PRESSURE AT 60 MIN WERE NOT SIGNIFICANT. THE EFFECT ON 24-H AMBULATORY SYSTOLIC AND DIASTOLIC BLOOD PRESSURE OF REGULAR DRINKING OF GREEN TEA
[INCREASES OF 1.7 MMHG(95%CI-1.6 TO 5.0) AND 0.9 MMHG(95%CI-1.3 TO 3.1), RESPECTIVELY] OR BLACK TEA[INCREASE OF 0.7 MMHG(95%CI- 2.6 TO 4.0) AND DECREASE OF 0.7 MMHG(95%CI-2.9 TO 1.5), RESPECTIVELY] WAS NOT SIGNIFICANT RELATIVE TO CAFFEINE. TEA
INGESTION CAUSED LARGER ACUTE INCREASES IN BLOOD PRESSURE THAN CAFFEINE ALONE. HOWEVER, ANY ACUTE EFFECTS OF TEA ON BLOOD PRESSURE DID NOT TRANSLATE INTO SIGNIFICANT ALTERATIONS IN AMBULATORY BLOOD PRESSURE DURING REGULAR TEA CONSUMPTION. |