• By Maureen Williams, ND

Herbal Defense Against the Common Cold

A special fiber from the bark of the larch tree, called arabinogalactan, may be another weapon in the arsenal against the common cold, according to a study that found that people who supplemented with arabinogalactan got fewer colds.

The study, published in Current Medical Research and Opinion, included 199 people who reported getting colds frequently—at least three times in six months. They were assigned to receive either 4.5 grams (about 1 teaspoon) of larch arabinogalactan powder per day or placebo and were monitored for 12 weeks.

Larch arabinogalactan increased the body’s potential to defend against infection

Larch arabinogalactan users have fewer colds

Arabinogalactan appeared to make a small difference: 60% of the people in the supplement group got a cold during the study compared to 74% in the placebo group and the arabinogalactan users had more cold-symptom-free days (77 days) compared to placebo (74 days). The duration and severity of symptoms was the same in both groups.

The study’s authors comment that “larch arabinogalactan increased the body’s potential to defend against common cold infection,” noting that both groups had fewer colds than expected during the study, suggesting that the protective effect of arabinogalactan may have been more pronounced if the rate of colds had been higher.

Arabinogalactan and immunity

While scientists still don’t know exactly how larch arabinogalactan works, studies done in test tubes have found that it can increase the activity of specific immune cells and increase antibody production. It is also known to act as a prebiotic, increasing populations of friendly bacteria in the large intestine. These bacteria help keep the immune system working properly, and studies have shown that increasing the number of friendly bacteria in the gut can reduce susceptibility to some infections, including colds.

Build your defenses against colds

Larch arabinogalactan may help your immune system better fight off cold viruses, but viruses are very clever and you might improve your odds staying healthy if you use multiple weapons to keep them at bay:

  • Gargle & rinse. A daily practice of gargling with plain water can keep your risk of colds down, and a traditional “neti pot” (sterilize before using) or any nasal saline rinse can help flush out bacteria or virus from your sinuses.
  • Rest. Lack of sleep and too much stress can wear down your defenses and increase your susceptibility.
  • Limit sugar. The higher your blood sugar level, the slower your immune cells work. Avoid spikes in blood sugar levels by eating high-fiber complex carbohydrates instead of sugars and refined grains.
  • Take vitamin C. Although we don’t know for sure whether it is preventive, studies have found that taking vitamin C during a cold may reduce its duration and severity. You need at least 1,000 to 2,000 mg per day to have an effect.
  • Take a cold rinse. Popular wisdom has it that cold water makes you stronger, and researchers have found it might be true: immune cells are more active after dunking briefly in cold water. Try taking a 30 to 60 second cold shower after your regular hot shower.

(Curr Med Res Opin 2013;29:1–8)

Maureen Williams, ND

Maureen Williams, ND, completed her doctorate in naturopathic medicine at Bastyr University in Seattle and has been in private practice since 1995. With an abiding commitment to access to care, she has worked in free clinics in the US and Canada, and in rural clinics in Guatemala and Honduras where she has studied traditional herbal medicine. She currently lives and practices in Victoria, BC, and lectures and writes extensively for both professional and community audiences on topics including family nutrition, menopause, anxiety and depression, heart disease, cancer, and easing stress. Dr. Williams is a regular contributor to TraceGains Newswire.

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