Hibiscus sabdariffa Linne (Malvaceae), a plant long used as a soft drink and medical herb in Taiwan, has been found to reduce blood lipids in animals. To investigate the cholesterol-lowering potential of H. sabdariffa extract (HSE) in human subjects, a clinical study was conducted using an oral preparation of HSE capsules. The study consisted of 42 volunteers who were observed over a period of 4 weeks. The volunteers ranged from 18 to 75 years old with a cholesterol level of 175 to 327 mg/dL. Subjects were randomly assigned to 3 groups: group I (1 capsule of HSE during each meal), group II (2 capsules), and group III (3 capsules). Serum cholesterol levels were determined at baseline before the study commenced and at 2 and 4 weeks of the treatment period. In general, taking HSE led to a significant decrease in serum cholesterol level in subjects from groups I and II after 4 weeks. After HSE had been administered for 2 weeks, serum cholesterol levels were found to be lower in all groups (P < .05 for groups I-III) compared with baseline values by 7.8% to 8.2%. A similar response was observed, a reduction in serum cholesterol level by 8.3% to 14.4%, after 4 weeks of taking the supplement. It is important to note that the serum cholesterol level for 71% of group II volunteers was significantly lowered with a mean reduction of 12% (P < .05). We conclude that a dosage of 2 capsules of HSE (with a meal) for 1 month can significantly lower the serum cholesterol level. The observation of lowered serum cholesterol in these subjects suggests that HSE may be effective in hypercholesterolemic patients.
