Chamomile is known for its natural soothing properties and is an ingredient in many herbal supplements.

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How can you know which herbal supplements are best? Here's information you need to sort the worthwhile from the worthless.

Aloe Vera

Aloe is a time-tested remedy for burns, including sunburn and skin irritations. No studies support recommendations to use aloe vera juice as a treatment for AIDS, diabetes, asthma, ulcers or impaired immunity, although a constituent, acemannan, may stimulate immunity. On burns, use a generous amount of gel scooped from cut whole aloe leaf or buy a lotion containing aloe as the primary ingredient.

Belladonna

Ingesting any part of belladonna or "deadly nightshade" can prove fatal. However, your doctor may use belladonna derivatives as treatment for stomach and intestinal cramping or as part of an eye exam. Inform your doctor if you've had any unusual past reaction to belladonna and take exactly as directed. Safer herbs for chronic stomach problems include ginger, DGL (deglycyrrhizinated licorice) and fennel seed.

Chamomile

Tea brewed from the tiny daisy-like flowers and feathery leaves of chamomile is an ancient but still popular herbal remedy to relax the nerves, relieve indigestion and heartburn. Some people find chamomile curbs insomnia and menstrual cramps. There also is scientific support for the use of chamomile cream for inflammatory skin diseases and wound healing. When buying tea, fragrance means freshness.

Echinacea

Studies have concluded that echinacea is effective in reducing the severity of cold symptoms and speeding recovery. It's widely sold in tablet and capsule form. However, experts recommend the more potent tinctures and extracts. Test potency by dissolving a small amount on the tip of your tongue. You should feel a strong numbing sensation. Not recommended for people with autoimmune disorders.

Ginkgo Biloba

Ginkgo biloba is primarily used to improve circulation, memory and to treat symptoms of Alzheimer's disease. Look for ginkgo products standardized to 24.0% ginkgolides (sometimes listed as ginkgo flavonoids or flavone gylcosides) for best effects. The recommended dose is 40 mg to 80 mg three times daily. Ginkgo may cause bleeding problems for those taking blood-thinning drugs like aspirin. Large doses can cause diarrhea, nausea, vomiting.

Red Clover

Red Clover is a "phytoestrogen" that can act like estrogen. As such, it may ease menopausal symptoms, protect against heart disease and osteoporosis. However, no studies document these effects nor the claims that it slows breast cancer. Dosage is 2 to 4 grams of dried flowers three times a day. Avoid the extract when pregnant or nursing.

SAM-e

SAM-e (S-adenosylmethionine), a dietary supplement sold as a prescription drug in Europe, can relieve arthritis symptoms and alleviate depression but costs more and may not work any better than glucosamine and chondroitin for arthritis or St. John's wort for depression, respectively. Don't combine SAM-e with prescription antidepressants.

Saw Palmetto

Saw Palmetto supplements can curb urinary problems caused by prostate enlargement common among middle-aged men. Noticeable results can occur in four to six weeks. Before taking saw palmetto, men should be evaluated for prostate cancer. The recommended dose is 160 mg of standardized extract twice daily.

Valerian

Valerian has a long history of use as a treatment for insomnia and anxiety. Several studies show valerian to be mildly effective, but how it works remains unclear. The recommended dose is a teaspoon of the tincture in a quarter cup of water or one to two tablets at bedtime. For anxiety, take half the dose. Don't take valerian with other sleeping aids.