Of the nearly 300,000 higher plant species (those that contain chlorophyll and perform photosynthesis), only 10 percent have been studied to identify their medicinal uses. While this may seem like a small percentage, it adds up to 3,000 herbs that can benefit our health. Some of these herbs, such as St. John's wort (Hypericum perforatum) and ginkgo (Ginkgo biloba), have been studied extensively, resulting in popular new additions to our medicine chests. Other, less common herbs have undergone fewer scientific studies, yet a long history of herbal tradition points to their efficacy, says herbalist Steven Foster, author of A Hundred and One Medicinal Herbs (Interweave Press). "Dozens of herbs fall into this category," explains Foster. "An example is burdock. There's hardly any good scientific information to back its long-standing use as a blood purifier, but it works nonetheless."
Health benefits of the not-so-popular herbs include ridding the body of free radicals, killing bacteria, stimulating the immune system, helping the body release toxins, and easing pain and inflammation. Here's a look at some of these lesser- known but highly beneficial herbs.
Borage (Borago officinalis)
Through the years, herbalists have used borage to treat a wide range of ailments from ulcers to frazzled nerves. An excellent source of the essential amino acid gamma-linoleic acid (GLA), borage can help diminish premenstrual syndrome symptoms such as mood swings, says Earl Mindell in his book Herb Bible (Simon & Schuster). This herb is an effective anti-inflammatory useful in ailments such as arthritis, and can be used as a tonic for stressed-out adrenal glands, according to David Hoffman, author of The Herbal Handbook (Healing Arts Press).
Burdock root (Arctium lappa)
An effective herb for detoxifying the body, burdock helps cleanse the blood, kidney, liver and lymphatic systems, says Brigitte Mars, an herbalist in Boulder, Colo. Burdock is a diuretic and mild laxative and helps stimulate bile flow, thus improving digestion, she adds. One study shows burdock's ability to scavenge free radicals in the body (American Journal of Chinese Medicine, 1996, vol. 24, no. 2).
Clove (Syzygium aromaticum)
Known for its mild anesthetic properties, this is a favorite herb for soothing toothaches. Clove has also shown activity against intestinal parasites and against a penicillin G resistant strain of Staphylococcus aureus (American Journal of Chinese Medicine, 1994, vol. 22, no. 2). In addition, terpenes found in cloves display promise as anticarcinogenic agents (Journal of Natural Products, 1992, vol. 55, no. 7).
Devil's claw (Harpagophytum procumbens)
As an anti-inflammatory, this herb helps reduce gout and arthritis pain and promotes joint flexibility. Several studies support positive anti-inflammatory effects of devil's claw on degenerative rheumatism. This herb can also help reduce cholesterol and uric acid blood levels, according to James Duke, Ph.D., in CRC Handbook of Medicinal Herbs (CRC Press).
Grapeseed (Vitis vinifera)
Grapeseed extract is a rich source of proanthocyanidins, which have health-promoting effects, especially when bound to other proanthocyanidins to form procyanidolic oligomers (PCOs). These include the ability to increase vitamin C levels in the body, decrease capillary fragility, scavenge free radicals, and inhibit collagen destruction, writes Michael Murray in The Healing Power of Herbs (Prima).
Kudzu (Pueraria lobata)
This herb has been used in traditional Chinese medicine to treat hangovers. Studies show it can also help treat alcoholism. Researchers found laboratory hamsters that consumed large amounts of alcohol lost interest in alcohol after being fed kudzu extract (Alcoholism: Clinical and Experimental Research, 1993, vol. 17, no. 6). Two isoflavones in kudzu, daidzin and daidzein, are believed to be responsible for this effect.
Mullein (Verbascum thapsus)
Mullein is often used in eardrops in combination with garlic as a bacteriostatic against middle ear infection. The mild expectorant and cough suppressant properties of mullein make it useful for treating sore throats and coughs.
Nettles (Urtica dioica)
A favorite of herbalist Mars, nettles help cleanse and nourish the kidneys and liver. As an expectorant, they help remove mucus from the lungs. Studies show that nettles are also effective in relieving allergies (Planta Medica, 1990, vol. 56, no. 1) and that this herb can prevent prostate cell growth, important in treating benign prostatic hyperplasia (BPH) (Planta Medica, 1994, vol. 60, no. 1).
Olive leaf (Olea europea)
Olive leaves have been successfully used to treat hypertension, according to Lawrence Review of Natural Products, 1997. One study demonstrates olive leaf's hypoglycemic activities, which may result from its ability to increase peripheral uptake of glucose as well as augment glucose-induced insulin release (Planta Medica, 1992, vol. 58, no. 6).
Purslane (Portulaca oleracea)
A rich source of omega-3 fatty acids and antioxidants, purslane helps protect cells from free radical damage, writes James Duke, Ph.D., in The Green Pharmacy (St. Martin's Paperbacks). High in magnesium, it helps maintain the health of muscles, bones and connective tissue. Purslane also has shown muscle-relaxing properties, probably due to its high concentration of potassium ions (Journal of Ethnopharmacology, 1993, 40, no. 3).
Turmeric (Curcuma longa)
Studies show that the volatile oil fraction of turmeric possesses anti-inflammatory properties useful in treating such ailments as arthritis and tendinitis, writes Murray in The Healing Power of Herbs (Prima). In addition, turmeric has shown remarkable anticancer properties, both in reduction of tumor development in mice (Journal of Cell Biochemical Supplements, 1997, vol. 27) and in symptom relief of external cancerous lesions [Tumori, 1987, vol. 73(1)].
Wormwood (Artemisia absinthium)
Wormwood has long been used to rid human and animal bodies of intestinal parasites. It has also shown fever-reducing abilities (Journal of Ethnopharmacology, 1985, vol. 14, no. 1), and in one study it helped protect the liver against acetaminophen poisoning, which validates the traditional use of this plant in hepatic (liver) damage (General Pharmacy, 1995, 26, no. 2). Duke warns that wormwood's active ingredient thujone is potentially dangerous. Use under the direction of your doctor.
Yarrow (Achillea millefolium)
Taken in hot water, yarrow causes sweating, which assists in reduction of fever and symptoms of the common cold, says herbalist Daniel Gagnon of Santa Fe, N.M. Chamazulene, a constituent of yarrow essential oil, has anti-inflammatory and anti-allergenic properties (Lawrence Review of Natural Products, 1998).
Yerba mansa (Anemopsis spp)
Gagnon's favorite lesser-known herb is yerba mansa. "It's an excellent herb for treating slow-healing conditions such as colitis and duodenal ulcers and can be used externally for skin ulcers and boils," he says. Use also as a sitz bath to help heal hemorrhoids. Gagnon adds that yerba mansa is a suitable alternative for goldenseal, an herb that is at risk of being overharvested in the wild.