Although the evidence behind echinacea has been mixed, a new study -- the largest to date -- found that taking a particular type of echinacea supplement throughout cold season reduced cold "events" (catching colds and days spent with colds) by 26%. See the update to the Echinacea Supplements Review for details about this particular supplement, including the special way it is taken. More >>

Studies have shown probiotics to reduce the duration and severity colds when taken throughout a cold season. A new study in children shows short-term use of a probiotic -- started at the time a household member gets sick -- also significantly reduces the duration and severity of acute respiratory infections. For details, including our tests of probiotic supplements, see the Probiotic Supplements Review >>

A recent study showed that taking a probiotic during allergy season reduced symptoms more than did a placebo — although not by much. For details, see the "What It Does" section of the Probiotic Supplements Review >>

Seaweed salts (also known as seaweed seasoning, kelp granules, or table kelp) can be used as salt substitutes, but cooking with them may result in the formation of toxic byproducts according to a recent study. Get the details in the Concerns and Cautions section of our Kelp Supplements Review.