Dandelion: bothersome weed or useful digestive aid?

Dandelion greens are popular in some parts of the country as an ingredient in soups and salads. They provide a very rich source of vitamin A, containing a significantly higher content than broccoli or Brussels sprouts, Chinese cabbage, kale, and collards. In addition, the roasted root of dandelion--and its extract--makes a useful coffee substitute.

Dandelion is approved for use as a natural flavor for various foodstuffs and is found in a wide range of health-food products, shampoos, soaps, and other personal cosmetics.

The common dandelion, Taraxacum officinale, a perennial herb, grows wild in meadows, pastures, and waste fields in the temperate zones of the northern hemisphere. It also goes by the name of Blowball, Priest's Crown, or Lion's Tooth.

The lowly dandelion is a member of the aster or daisy family. The commercially used product is collected from farms in eastern European countries.

Spring arrives on the shoulders of the dandelion whose flower seems to proliferate everywhere. Early in the season, a beautiful golden-yellow mosaic appears on lawns. Later, puff balls burst forth spawning thousands of tiny, floating seed-bearing parachutes across the neighborhood.

Traditional Usage

Dandelion enjoys a long history of use in traditional medicine for the treatment of diminished bile flow, digestive and gastrointestinal complaints, and poor appetite. It's found on the list of early tenth-century Arabian medicine. The root has been commonly put to work treating liver and kidney ailments. Early Native Americans looked to the dandelion to ease a variety of internal problems such as kidney disease and stomach pains.

Diuretic Properties

Dandelion is commonly used as a component in herbal diuretics (to increase urine flow). The leaves are combined with such herbs as juniper, buchu, goldenrod, yarrow, and uva ursi to produce a mixture with mild diuretic properties. These leaves are very high in potassium (they may contain up to 4.5 percent by dry weight). This helps compensate for potassium losses during increased urination.

Dandelion leaves, collected before flowering and dried before use, appear to have a greater diuretic effect than an extract of the root. The leaves contain bitter principles (sesquiterpene lactones) which many believe play a part in their diuretic effects.

These bitter compounds may also contribute to the mild anti-inflammatory activity of dandelion and may explain why some people have utilized dandelion extracts for muscular rheumatism and arthritic joints.

Dandelion also contains small amounts of flavonoids, phytosterols, and triterpenes. These phytochemicals can help reduce the risk of chronic diseases when taken in significant amounts.

The Root of the Matter

The root of the dandelion also improves bile secretion, serves in the treatment of dyspepsia (stomach upset), loss of appetite, and offers some diuretic properties. Roots should be harvested while the plant is flowering. The bitter compounds in the root help stimulate the digestion and appetite and may act as a mild laxative. Fresh root is believed to be more potent than dried.

When the root is harvested in the autumn, its inulin content is very high. Inulin, an indigestible polymer-like substance made from fructose, behaves like dietary fiber. During that season, the dried root may contain up to 40 percent inulin, while in the spring it contains only 2 percent.

Inulin, which is also found in onions and chicory root, appears to be useful in preventing intestinal infections by stimulating the growth of healthy bifidobacteria in the intestinal tract. It may also reduce the risk of colon cancer and can facilitate calcium absorption. In animal studies, dandelion extracts have manifested mild anti-tumor activity.

Dosage and Safety Issues

During spring-time, the young dandelion leaves may be eaten raw or lightly cooked. Four to 10 grams of chopped leaves or one to two teaspoons of powdered root can be boiled with one-half cup of hot water and then strained. This solution may be taken two to three times a day.

Generally, dandelion has a very low toxicity. Discomfort from dandelion products may result from stomach hyperacidity. In some individuals, the milky latex in fresh dandelion leaves may cause allergic contact dermatitis. Dandelions can also produce an allergic reaction in those individuals who are sensitive to members of the daisy or aster family (ragweed, marigolds, daisies, chrysanthemums, and other flowers).

People with bile duct obstruction or inflammation of the gallbladder should not use any dandelion product. Furthermore, those with gallstones should not use the herb unless they are under the supervision of a physician. Dandelion appears to be safe to use during pregnancy and lactation.

Winston J. Craig, Ph.D., R.D., is professor of nutrition at Andrews University, Berrien Springs, Michigan.