Here's a little good news for folks who suffer with canker sores: There's a new, effective treatment for the painful mouth ulcers. The results of a recent study confirmed that applying licorice root extract to canker sores can reduce ulcer size and speed healing.

In clinical trials conducted by researchers at the University of Washington, 80 percent of canker sore sufferers using an oral patch containing licorice root extract experienced significant pain reduction in just three days. Canker sores treated with the extract shrank to one-tenth their original size after seven days, while those left untreated grew larger and continued to cause pain.

The results of this trial add validity to the findings of a previous study, in which 96 percent of canker sores treated with licorice root extract-impregnated oral patches experienced significant healing within three days.

In reality, the "new" treatment for canker sores is based on an ancient remedy: Licorice root extract has been used as a healing agent for more than 4,000 years. With the introduction of prescription drugs in the 1900s, licorice root was promptly booted out of the medicine cabinet and into the spice rack.

Best known for its sweet taste and distinctive flavor, licorice is still a popular ingredient in a number of candies, tobaccos and beverages. Fortunately, the benefits of the plant extract are being rediscovered by modern-day healers.

Licorice is a rich source of beneficial compounds that are useful in the treatment of arthritis, viral infections and even cancer. The medicinal properties of these natural agents have been well established by long-term clinical use and recent scientific evidence.

One active ingredient in licorice root, glycyrrhizin, has been shown to have potent anti-inflammatory properties. By soothing and coating injured tissues in the mouth, glycyrrhizin helps provide rapid relief for the common canker sore.

Canker sores, also known as recurring aphthous ulcers, are painful lesions inside the mouth. While they don't appear to be contagious, they are extremely widespread, affecting an estimated one in five Americans.

The most common types of canker sores, which doctors refer to as minor aphthous ulcers, aren't exactly huge — they're shallow craters, just about the width of a pencil eraser — but they can lead to enormous suffering. The pain they cause can interfere with eating, drinking, speaking, kissing and the quality of life in general.

Although the exact cause of canker sores is unknown, genetic predisposition is believed to play a major role. Individuals with parents who suffer from the ulcers are highly likely to develop them, as well.

Other possible causes include food allergies and hormonal fluctuations. Even minor mouth trauma, caused by the sharp edge of a potato chip, a sip of scalding liquid or an accidental nip of the teeth, can lead to the development of a painful aphthous ulcer.

Most common over-the-counter remedies for canker sores are designed either to numb the pain or to cover the ulcer with a protective coating. For some canker sore sufferers, these treatments are not only inadequate, they're often more annoying than the ulcers themselves.

Licorice root extract doesn't just numb the injured tissue or cover the sore, it reduces pain and helps speed healing. Even better, it offers a few bonus benefits.

Compounds isolated from licorice root may help prevent tooth decay, according to researchers at UCLA. In test tube studies, the scientists demonstrated that extract from the plant root contains at least two compounds that are capable of inhibiting streptococcus mutans bacteria, a major cause of dental cavities.

Researchers at Rutgers University tested the effects of licorice root extract on tissues taken from prostate and breast cancer tumors. The scientists demonstrated that compounds in the substance effectively stopped the growth of cancer cells with minimal damage to normal, healthy cells.

The active ingredients in licorice root extract belong to a class of organic chemicals known as polyphenols. Related substances include the cancer-fighting compounds found in green tea and red wine.

Licorice root also contains compounds that can increase retention of fluid and sodium. While these properties make it useful for reducing excessive thirst when water is scarce, they can also lead to an unwelcome elevation in blood pressure.

Individuals diagnosed with high blood pressure, heart problems or other chronic medical conditions shouldn't use licorice without first discussing it with their physicians. But for healthy folks suffering from painful, recurrent canker sores, a little licorice root could go a long way toward making life more comfortable.

Rallie McAllister is a board-certified family physician, speaker and the author of several books, including "Healthy Lunchbox: The Working Mom's Guide to Keeping You and Your Kids Trim." Her website is www.rallieonhealth.com. To find out more about Rallie McAllister, M.D., and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com.

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