By Adam Martin
May 14, 2013

Echinacea is consistently among the top-selling supplements, with U.S. consumers typically spending more than $100 million on it every year. But a study published recently in The New England Journal of Medicine (NEJM) panned the herb, saying it doesnt prevent colds or make symptoms less annoying. The lead researcher—Ronald B. Turner, MD, a pediatrics professor at the University of Virginia—thinks most of the evidence in favor of echinacea is far too weak to make it a reasonable remedy. Naturally, echinacea supporters disagree. And they recently panned Turners findings, saying the amount of echinacea used in his study was roughly three times less than what veteran herbalists recommend.

Recently, I visited an echinacea farm run by one of Europes most respected makers of natural products, Bioforce AG. Instead of allowing the plant to dry out first, Bioforce transforms it into a cold remedy within hours of harvesting. Company scientists say drying seems to snuff out the unstable immune boosters in echinaceas purple flowers, leaves, stems, and roots—a theory endorsed by leading U.S. herb experts who have studied and used the plant for years.

Now I understand why my hot cup of echinacea tea isnt working. That form, like the drying process, basically defangs echinaceas active ingredients, according to botanist James A. Duke, PhD, a member of Health magazine's Advisory Board and author of the Green Pharmacy Herbal Handbook. Those pills you can buy in any drugstore are also of little use, because chances are theyre made from dried plants. Plus, a typical pill dosage is hopelessly short on enough immune-boosting power to tame a cold. (I should note that some herbalists claim the pills work well, but most dont believe that.)

Most herb pros seem to agree that youll have good luck with a tincture, or alcohol-based extract, made from fresh herbs. Unfortunately, few supplement companies make tinctures with fresh echinacea. Try calling the manufacturer to ask before you buy—and see An Update on Echinacea: Dos and Donts for a list of brands recommended by professional herbalists.

Whatever brand you choose, youre likely to keep on sniffling if youre stingy with the bottle. When you dont take enough, “its like sprinkling fairy dust on your cereal,” warns Steven Foster, who has studied echinacea and other herbs for a quarter-century. Foster, author of Echinacea: Natures Immune Enhancer and co-author of the just-published National Geographics Desk Reference to Natures Medicine, says he takes 1 to 2 teaspoons of a tincture (mixed with a little water) every 2 to 4 hours when hes coming down with a cold. Thats at least three times the amount used in the NEJM study.