Lemongrass, a group of grasses in the genus Cymbopogon, is a perennial plant native to warm climates. A favored herb in Asian cooking, lemongrass imparts a pleasant citrus flavor and aroma to many dishes. Lemongrass essential oil has a variety of medicinal and practical uses, including several cholesterol-lowering effects.
Lemongrass oil contains terpenoid compounds such as geraniol and citral that decrease cholesterol levels, according to Ronald Ross Watson, author of the book "Vegetables, Fruits, and Herbs in Health Promotion." These compounds inhibit the production of mevalonic acid, an intermediary in the production of cholesterol and the target of many cholesterol-lowering pharmaceutical drugs. Doses of 140 mg per day of lemongrass oil have produced cholesterol-lowering benefits.
Chronic inflammation, which leads to increased risk for cardiovascular disease, may be suppressed by lemongrass oil, according to an Indian study on laboratory animals published in the October 2010 issue of the journal "Food and Chemical Toxicology." Inflammation is one of the initiating factors in atherosclerotic plaque formation. In the study, 5 mcg and 10 mcg. doses of lemongrass oil extract significantly increased activity of the antioxidants superoxide dismutase and glutathione peroxidase and decreased levels of molecules that promote inflammation. In particular, lemongrass oil decreased levels of malondialdehyde, a marker of oxidized lipids, in certain white blood cells that are associated with atherosclerosis. Futher human trials are needed to confirm these preliminary results.
Terpenoids in lemongrass influence genes that improve insulin resistance and decrease circulating lipid levels, according to a Japanese study published in the June 2010 issue of the journal "PPAR Research." These compounds may be helpful for managing diabetes, obesity and elevated cholesterol levels in some people, say the researchers.
Brazilian researchers found that lemongrass oil decreased cholesterol levels in a short-term study published in the September 2011 issue of the journal "Food and Chemical Toxicology." In the study, laboratory animals consumed either 10 mg or 100 mg per kilogram body weight of lemongrass essential oil for 21 days. Results showed that the higher dose, which is similar to doses used in traditional herbal medicine, significantly reduced cholesterol levels.
Toxicity of lemongrass is low when used in low doses, according to the website Drugs.com. Lemongrass may be nontoxic in doses as high as 3.5 g per kilogram body weight. You can also consume lemongrass oil by drinking lemongrass tea, made by infusing the leaves, which contain 0.4 percent essential oil, in hot water.