Authors:

Abstract

Most Hibiscus tea are made with Hibiscus rosasinensis and are expensive. Although these tea are marketed indicating hypoglycemic effects, scientific data are lacking on the effect of H. rosasinensis on humans.

The objective of the study was to determine the effect of home-made water extract of H. rosasinensis flower (HRWE) as a tea on post-prandial blood sugar level (PPBS) of healthy individuals compared to green tea (GT) and commercially available Hibiscus tea (CHT–H.rosasinensis+Rosehip).

Fasting and PPBS [after consuming a standard diet (StD=1045Kcal), StD+GT, StD+CHT and StD+HRWE on separate days] at 15, 30, 45, 60 and 120 minutes of healthy volunteers (n=14) were measured by glucose oxidase colourimetric assay kit method. Data were plotted on graphs as glucose concentration vs time. The mean of incremental area under the curves (IAUC) was estimated. Data were analyzed using SPSS.

IAUC for GT, CHT and HRWE (2763, 2580 and 2977) were significantly lower than IAUC for control (4758). No significant difference was observed between GT, CHT and HRWE.  Although not significant, 2 hour-PPBS values of GT, CHT and HRWE were lower than that of control. Compared to control, a peak blood glucose reduction of 13.3%, 10.5% and 14.1% were observed for GT, CHT and HRWE respectively. Compared to control, significant PPBS reductions at 30, 45 and 60 minutes with GT and HCT were observed while significant reductions at 15, 30, 45 and 60 minutes were observed with HRWE (p<0.05).

It can be concluded that GT, CHT and HRWE significantly lower PPBS of the standard meal.The effect of HRWE on PPBS is comparable to GT and CHT.   

Keywords: Hibiscus rosasinensis, Hibiscus sabdariffa, Green tea, Post-prandial blood glucose, Blood pressure