[01] Lavenash a/l Mohan, Faculty of Medicine, Melaka-Manipal Medical College (Manipal Academy of Higher Education), Melaka, Malaysia. [02] Bhageeta a/p Gajendran, Faculty of Medicine, Melaka-Manipal Medical College (Manipal Academy of Higher Education), Melaka, Malaysia. [03] Tan Ching Ping, Faculty of Medicine, Melaka-Manipal Medical College (Manipal Academy of Higher Education), Melaka, Malaysia. [04] Abu Emmil Qawarizmi Bin Abu Sofian, Faculty of Medicine, Melaka-Manipal Medical College (Manipal Academy of Higher Education), Melaka, Malaysia.

The objective of this randomized controlled trial was to evaluate the acute effects of green tea consumption on alertness and blood pressure among medical students in MMMC. After filling up a pre-intervention questionnaire, blood pressure and pulse rate were measured. Each intervention group participant was given 200 ml of high dose green tea (1.5g green tea brewed in 200ml boiled water). Each control group participant was given 200 ml of low dose green tea (1.5g green tea brewed in 2000ml boiled water). Blood pressure, pulse rate and reaction time were measured after 15 minutes, and post-intervention questionnaire were filled up. For high dose green tea, the mean difference of SBP between pre and post consumption was 0.60, 95% CI (-2.82 to 4.02), p value (0.723), whereas mean difference of DBP between pre and post consumption was -1.27, 95% CI (-5.34 to 2.80), p value (0.529). For low dose green tea, the mean difference of SBP was 6.43, 95% CI (1.92 to 10.95), p value (0.007) whereas the mean difference of DBP was 4.63, 95% CI (2.90 to 6.37), p value (<0.0001). The mean difference of reaction time between the two groups was -1.8ms, 95% CI (-54.4 to 50.9), p value (0.947). Based on the study done, it can be concluded that green tea in low doses does have immediate effect on the individual’s blood pressure (lowers blood pressure) but not alertness and pulse rate. However, high dose green tea does not have significant immediate effects on the individual’s blood pressure, alertness and pulse rate.

Green Tea, Medical Students, Blood Pressure, Reaction Time, Randomized Trial

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