Medicinal Uses and Indications
Licorice root is used for a variety of conditions.
DGL is often suggested as a treatment for stomach ulcers, although it's not clear whether it works. A few studies have found that DGL and antacids helped treat ulcers as well as some prescription drugs. However, since antacids were combined with DGL, it's not possible to know how much of the benefit came from DGL alone.
One animal study found that aspirin coated with licorice reduced the number of ulcers in rats by 50%. (High doses of aspirin often cause ulcers in rats.) In one study, licorice root fluid extract was used to treat 100 patients with stomach ulcers -- 86 of whom had not improved with conventional medication -- for 6 weeks. Ulcers disappeared in 22 people; 90% of participants got better. Other studies have found that DGL had no effect on peptic ulcers in humans.
Canker sores (Apthous ulcers)
One small study found that people with canker sores who gargled 4 times per day with DGL dissolved in warm water found pain relief.
In one study, licorice gel, applied to the skin, helped relieve symptoms of itching, swelling, and redness. A gel with 2% licorice worked better than a gel with 1% licorice.
Dyspepsia (indigestion, GERD)
Preliminary studies suggest that a specific herbal formula containing licorice, called Iberogast or STW 5, may help relieve symptoms of indigestion or gastroesophageal reflux disease (GERD). This herbal formula also contains peppermint and chamomile, two herbs often used for indigestion.
Upper respiratory infections (cold, cough)
Licorice is a traditional treatment for cough, asthma, and sore throat. One study found that gargling with licorice before getting anesthesia cut the incidence of postoperative sore throat by half.
One study found that a preparation of licorice may reduce body fat. Fifteen people of normal weight consumed 3.5 g of licorice each day for 2 months. Body fat was measured before and after treatment. Licorice appeared to reduce body fat mass and to suppress the hormone aldosterone; however, the people in the study retained more water.
Another study found that a topical preparation of glycyrrhetinic acid (a component of licorice) reduced the thickness of fat on the thigh in human subjects. A third study found that people who took 900 mg of licorice flavonoid oil daily for 8 weeks experienced reductions in body fat, body weight, body mass index, and LDL cholesterol levels. More studies are needed to say if licorice really helps reduce fat. In addition, taking licorice long term has a number of health risks.
People who regularly take large amounts of licorice -- more than 20 g/day -- may raise blood levels of the hormone aldosterone, which can cause serious side effects, including headache, high blood pressure, and heart problems. For people who already have high blood pressure or heart or kidney disease, as little as 5 g/day can cause these side effects. More research is needed.
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