Travel through Jamaica or Mexico and you're likely to be offered a hibiscus-flavored soda. Ill in China? If it's your liver or blood pressure that's the problem, a traditional healer might treat you with hibiscus. Although, it's not found in many foods or medicines in the United States, new research suggests Americans might want to warm up to the flower to improve their health.
What the researchers wanted to know: Can hibiscus flowers help prevent the build-up of cholesterol?
What they did: The scientists boiled the flowers and filtered the solution to obtain concentrated hibiscus extract. First, they tested the effects of the extract on cholesterol in samples of human blood. Then, they used two groups of 24 rats each; they fed one group a high-sugar diet and one a high-fat diet. Within each group, some rats were given hibiscus in addition to their unhealthy diet. (Some rats in each group were also fed a normal diet as controls.) The scientists compared the cholesterol levels of the rats given hibiscus with those who ate just an unhealthy diet.
What they found: For rats on the high-sugar diet, hibiscus significantly reduced triglyceride levels in the blood. (Triglycerides are a reflection of fat intake and can contribute to high cholesterol levels.) For the rats on a high fat diet, hibiscus reduced the levels of total cholesterol in the rats' blood and especially reduced the amount of LDL or "bad" cholesterol. Based on their experiments with human blood in the lab, the scientists think that hibiscus makes it harder for LDL cholesterol to bind to artery walls, inhibiting the build-up of cholesterol that can cause blockage and heart disease.
What it means to you: Add hibiscus to the list of heart-friendly foods. Like red wine, tea, and even grape juice, hibiscus contains antioxidants and could help your heart.
Caveats: Rats are not people and, though similar effects have been found in rabbits, there is no direct evidence, as yet, that hibiscus reduces levels of cholesterol in humans. (Studies have shown, however, that the flower is completely ineffective against head lice.)
Find out more: The National Institutes of Health has an explanation of cholesterol, as well as a list of recommended foods to help lower cholesterol.
Purdue University has a description of the type of hibiscus these scientists used, Hibiscus sabdariffa, complete with pictures and ways to prepare the flower to eat.
For more information on how to reduce blood pressure and your risk of heart disease with certain foods, check out this U.S. News health brief: http://www.usnews.com/usnews/health/briefs
Read the article: Chen, C. et al. "Inhibitory Effects of Hibiscus Sabdariffa L Extract on Low-Density Lipoprotein Oxidation and Anti-Hyperlipidemia in Fructose-Fed and Cholesterol-Fed Rats." Journal of the Science of Food and Agriculture. Published online Sept. 15, 2004 and will be published in the print journal later.
Abstract online: http://www3.interscience.wiley.com