Who'd have ever thought that the soaring popularity of a bunch of healthful plants would jam the aisles of every health food store in town? The herbal ways of healing have hit the mainstream, and today even the most suburban of medicine cabinets are stocked with "alternative" tinctures, pills and teas.But what really works? Here's what those in the know have to say: Echinacea Even just a few years ago, most mainstreamers had never even heard of this vowel-laden plant, but suddenly it's everywhere. Even the most conventional of pharmacies and the most traditional of medicine-takers have caught on to the healing qualities of echinacea. Herbalists say its the leader of the pack in enhancing the immune system -- for one thing it stimulates the production of interferon, the body's own antibiotic; for another, it prevents the spread of microorganisms, viruses and other toxins in the human body. Studies have shown that echinacea even increases the activity of white blood cells.The head of the vitamin department at Oasis, Nancy, likens a squirt of echinacea tincture into a glass of water to a "suit of armor" for the immune system. While the most common use of echinacea is to beat off the common cold or flu symptoms, an herbal information web site says it can also be used in combination with the herb goldenseal to treat bladder infections. But just as echinacea finds widespread acceptance, some research is indicating the remedy may have a dark side: Recent studies have shown that echinacea can actually replicate the HIV/AIDS virus, so those infected with the virus should steer clear of this particular herb.GoldensealThis bitter-tasting plant, indigenous to the U.S., is also gaining public acceptance (though in a lesser manner than echinacea) as a preventive medicine. But those who want to explore its powers better act quick: Goldenseal is on the endangered species list because vast amounts of its habitat have been destroyed.During flu season, those afflicted often turn to goldenseal for soothing the inflamed membranes of the digestive system. According to the Herb World News Online web page, goldenseal is also used for gastritis, diarrhea, hemorrhoids and habitual constipation. The web page, however, warns that those who have any cardiac problems should avoid goldenseal, as the herb is known to raise blood pressure.ZincOnce you see "alternative" remedies advertised during an episode of "Seinfeld," you know they have caught the attention of the corporate culture. Zinc is the perfect example. Suddenly, pharmaceutical giants across the country are hawking throat candies saturated in zinc. Why? Because the mineral, essential to the well-being of the human body, speeds healing. Nancy, Oasis' herb maven, says that taking zinc in lozenge form helps stop the virus from gathering steam because the zinc is "absorbed directly where needed as it dissolves."What a wonder! And the benefits continue: Zinc is also an antioxidant, meaning it aids in the regeneration of the body.AntioxidantsBesides zinc, antioxidants include vitamins A, C and E, and selenium (a mineral).Jo Serrentino, in her book How Natural Remedies Work, describes how antioxidants protect against damage from environmental factors, as well as help the body bounce back during an illness. She cites how vitamin E, for instance, can protect again ozone and nitrogen dioxide damage to the lungs from the atmosphere. Also, people undergoing chemotherapy have found antioxidants are good boosts for the immune system.Mental Health HerbsOasis reports that its current biggest seller in the herb department is St. John's wort, a phenomena that is due in part to the power of the press. This little plant -- often called the "natural Prozac" -- has been the topic of endless health reports in Time, Newsweek, The New York Times and on network television news shows. Feeling blue? The reports suggest swallowing a capsule or a little glass of tincture and water could help chase away the clouds of mild anxiety and depression.At least some of the claims aren't groundless. Physicians in Germany commonly prescribe St. John's wort for depression before resorting to drugs such as Prozac, Zolof or other anti-depressants that are so commonly prescribed in the U.S.Eva Edelman, the Eugene author of Natural Healing for Schizophrenia and Other Common Mental Disorders, says some studies have indicated St. John's wort is also helpful for severe emotional or mental conditions. The herb eases headaches, hysteria, nerve pain and certain types of anxiety and sleep disorders, she says.One warning about St. John's wort: It's not a miracle drug. The results of its ability to soothe come slowly, and only after diligent and careful use. Kava is another plant that has popped up as useful in the treatment of anxiety syndromes. A recent German study showed that people on a regular regimen of kava showed significant improvements, and the herb created no adverse effects. Edelman advocates its use, as well, for anxiety, insomnia, nervousness and restlessness. She does note, however, that kava "can increase sensitivity to sound, light and movement." Ginkgo is yet another herb on the popularity bandwagon -- especially after widespread reports indicated that by increasing circulation to the brain, it can actually improve memory and probably helps to slow the onset of Alzheimer's disease. The Journal of the American Medical Association, in a study published in October 1997, reported that 27 percent of those who received 26 or more weeks of ginkgo treatment had improved memory, daily living and social behavior.A Nice (and Healing) Cup of TeaDon't like swallowing pills? Want to avoid the vodka or brandy content in most tinctures? Another lovely way to consume healing herbs is through a hot cup of tea.Some herbalists say tea doesn't have the bang of the other methods of consumption because it's just not concentrated enough. But Erica, one of Sundance's herb doyens, believes teas can heal just as well as other forms and suit some people to, well, to a "T." Elderflower, horehound, peppermint, yarrow and elecampane are teas most commonly used for cold remedies. Elderflower and yarrow are the fever-fighting herbs, while the others act as expectorants to soothe coughs and loosen phlegm.Women who are searching for ways to maintain a healthy hormonal balance -- naturally or in addition to hormonal replacement therapies -- have discovered black cohosh tea. The herb is effective in raising estrogen levels, making it useful for pre-menopausal symptoms such as hot flashes. Edelman describes black cohosh as "a normalizer of the female reproductive system."Then there's the "coolest" of the current popular teas, touted to vastly improve overall health: kombucha. Nancy, from Oasis, says "miracles" have been attributed to this concoction, though no evidence has been scientifically documented. The preparation of kombucha tea is as follows: Find someone with a kombucha log and ask for one of the mushrooms off that log. Put the mushroom in a gallon jug. Brew black tea and add sugar. Pour the tea over the mushroom and let it sit in the refrigerator until it sprouts another mushroom. Give the second mushroom away and drink the tea. Heather Thompson, owner of Mrs. Thompson's Herb, Gifts and Folklore at 12th and Lincoln, has a store-full of herbs -- the vast majority of them, she says, are useful as teas. Thompson describes the most popular sellers as nettles -- high in nutrients and a good replacement for vitamin supplements -- and peppermint, which she says many people turn to as a way to quit caffeine. Lavender and raspberry leaf are other big-selling herbs. Raspberry leaf tea is helpful to women in strengthening the uterus and giving some ease to menstrual cramps, she says, while lavender flowers can be used in sachets to help promote relaxation.Those interviewed about herbal remedies have confidence in the plants' abilities to heal, but all also warned that advice about using herbs is just that -- advice! This article is meant as a general guide to popular herbal remedies, and not as any kind of medical prescription.