The candy canes that adorn Christmas trees throughout the holiday season are flavored with menthol, an extract of mint, and that might be a good thing. Government scientists are studying this family of popular herbs for their potential medicinal uses.
Peppermint, spearmint, pennyroyal and other members of the mint family are rich sources of antioxidants--chemical substances that are proving useful in preventing illnesses ranging from cancer and heart disease to cataracts. Although generally not eaten in quantities large enough to affect nutrition, fresh mint leaves are rich in Vitamin C and beta-carotene, which the body converts to Vitamin A. Both vitamins are among the nutrients that the National Cancer Institute, the National Academy of Sciences and other public-health groups recommend Americans consume more of, to reduce their risk of developing cancer.
Researchers are also looking at a variety of medicinal possibilities for the flavoring extract menthol itself. "Menthol acts as a local anesthetic, vascular stimulant and disinfectant," says James Duke, a botanist with the U.S. Department of Agriculture's Research Service in Beltsville, Md., "and may be rubbed on affected areas or inhaled."
But too much menthol--or too much of any mint oil--can be dangerous. "The caveat is always moderation," Duke says.
The notion that mint might have some medicinal uses is not new. In medieval times, mint was strewn about the home for its aroma, and pennyroyal was used as a method of ridding houses of fleas--the "penny" part of its name actually comes from a Latin word for "flea-repellent."
By the 18th Century, mint had gained importance as a medicinal herb, and as Rodale's "Illustrated Encyclopedia of Herbs" notes, "Various species were used as a cure for colic, digestive odors and a host of other problems." Among them, Japanese mint was thought to be good for birth control, while a mixture of peppermint, spearmint and salt was applied to dog bites.
A century ago, the British medical journal Lancet reported that peppermint oil applied to the temples could help relieve a headache, says Roy Genders, author of "The Complete Book of Herbs and Herb Growing." When rubbed into the gums, peppermint oil purportedly alleviated toothache pain. Peppermint water helped relieve indigestion, says Genders, and soothed morning sickness and seasickness.
Today, researchers are concentrating on menthol. Mint leaves contain up to 3% oil, which is extracted by a distillation process similar to that used to make alcohol. The resulting menthol, Duke says, is used in a variety of ways, from overcoming bad breath to reducing the pain of rheumatism.
Peppermint tea is a popular way of consuming the plant. "Could antioxidant mint tea be the fountain of youth?" Duke asks rhetorically. "Probably not. But evidence accumulates to show that antioxidants . . . may slow aging, arthritis, cancer, cataracts and viruses."