Benefits Of Citrus Peel Extract

Health authorities and the general public have long recognized the value of citrus fruits as a rich source of vitamin C. The addition of citrus to the diets of sailors wiped out the scourge of scurvy by the end of the 18th century. However, more recent research into the health benefits of citrus fruits has focused on the medicinal properties of the phytochemicals found in their peels.

Reduces Skin Cancer Risk

Researchers at the Arizona Cancer Center, based at the University of Arizona, explored the relationship between the consumption of various citrus products and the risk of squamous cell carcinoma, a skin cancer diagnosed fairly often in the states of the Sun Belt. They found that citrus consumption was fairly widespread among their study group of older Arizona residents. Although the researchers found no link between overall citrus juice and fruit consumption and the incidence of the skin cancer, they discovered that study subjects who regularly consumed citrus peel -- a rich source of d-limonene -- had a significantly lower risk of this form of skin cancer. In reporting their results in a 2000 issue of "Nutrition and Cancer," researchers called for further studies to confirm citrus peel extract as a skin cancer preventive agent.

Antioxidant Properties

To pinpoint the richest source of antioxidants among various citrus products, Portuguese researchers quantified the level of free radical scavenging potential in the peels and juices of several commercially cultivated citrus fruits. Among the citrus species tested were sweet orange, known scientifically as Citrus sinensis; lemon, or Citrus limon; grapefruit, or Citrus paradisi; and lime, or Citrus x aurantiifolia. In an article in the January 2010 issue of "Food and Chemical Toxicology," the researchers reported that the peel extracts from all citrus species showed greater antioxidant properties than the extracts from their respective juices. Researchers recommended using the whole peel extract rather than isolating and using individual antioxidants from the extract because the former approach takes advantage "of additive and synergistic effects of different phenolics, flavonoids, ascorbic acid, carotenoids and reducing sugars present in the samples."

Reduces Bad Cholesterol

Citrus peel extract appears to have significant cholesterol-lowering properties, according to Andreas Moritz, author of "Timeless Secrets of Health and Rejuvenation." He cites a study in which test subjects were given either a widely prescribed statin drug or policosanol extracted from citrus peels. Among those receiving policosanol, the level of low-density lipoprotein, the so-called bad cholesterol, dropped by an average of 19.3 percent compared with an average decrease of 15.6 percent for those getting the statin.

May Help Prevent Diabetes

Researchers at the University of Hawaii conducted an animal study that found that the polymethoxylated flavones, or PMFs, found in citrus peel extract may hold promise as a diabetes preventive agent. Test animals were fed a diet high in fructose to sharply increase their level of triglycerides and their resistance to insulin. Researchers then treated one group of test animals with low daily doses of PMF, another with high daily doses of PMF and still another with nothing. Both groups receiving PMF supplements showed a significant reduction in triglyceride levels and a sharp reduction in their resistance to insulin. Researchers published their findings in the June 2006 issue of "Life Sciences."