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It's the season when many of us will come down with the common cold. And if you have kids in school, chances are you'll get hit more than once.

With the inevitable misery of cold season, many Canadians stock up on natural remedies to help relieve sore, scratchy throats, sneezing and runny noses.

One popular cold fighter is echinacea, an herbal remedy believed to boost the body's immune system and lessen the duration and severity of cold symptoms.

But according to a study published Tuesday in the Annals of Internal Medicine, it's a supplement that offers little relief.

Previous studies - several hundred in fact - have tested echinacea for preventing or treating colds with mixed results.

In the current study, researchers from the University of Wisconsin studied 719 people, aged 12 to 80, with early cold symptoms. Participants were assigned to receive either no pill, echinacea, or a placebo. Patients then recorded their symptoms twice a day for one week.

Compared to folks given no pills or placebos, those taking Echinacea had only a slight decrease in the duration of their colds. Echinacea users experienced, on average, a 10 per cent reduction (seven to 10 hours) in the duration of theirweek-long cold, a finding that wasn't deemed statistically significant (e.g. it could have happened by chance).

As well, there was no significant decrease in the severity of cold symptoms between echinacea users and non-users.

In truth, there's very little you can do to fight the common cold because we have no way to attack the 200-plus viruses that cause colds.

That said, there's growing evidence that some natural health products can offer cold relief, at least to a modest degree. Studies suggest the following alternative treatments might take the edge off your cold.

(Before taking any herb or supplement, speak to your doctor if you are pregnant, have a medical condition, or take medication that may interact with certain supplements.)

Vitamin C

Data does not support the notion that taking vitamin C will prevent you from catching a cold, but as a treatment, the evidence is much better. Most studies show that vitamin C can decrease the duration of a cold by 24 to 36 hours.

To reduce cold symptoms, take 2,000 milligrams of vitamin C a day, in divided doses (e.g. 500 milligrams four times a day). The supplement appears to be most effective in children, people under physical stress and those with low dietary intakes of vitamin C.

Taking high doses of vitamin C for prolonged periods may increase the risk of kidney stones. People with a history of kidney stones should restrict their intake to 100 milligrams a day.


Zinc lozenges are a popular treatment for colds and most studies suggest they do ease symptoms and speed up recovery in adults. It's believed that zinc may block the replication of cold viruses.

Lozenges of zinc gluconate or zinc acetate should be taken every two hours while awake, starting within the first 48 hours of symptoms. Most zinc lozenges contain 10 milligrams of zinc. Do not take more than 50 milligrams (5 lozenges) of zinc a day; too much zinc can depress immune function.


Clinical studies have found this special extract of North American ginseng, made by Afexa Life Sciences Inc., is effective at reducing the frequency, severity and duration of colds in healthy adults and seniors by boosting the immune system.

The recommended dose of Cold-FX is 200 milligrams, twice daily, during cold and flu season. Cold-FX Extra Strength is a higher dose to be used short-term at the first sign of cold symptoms.


These friendly strains of bacteria added to yogurt and sold as supplements are thought to stimulate the immune system. In adults and children, taking a daily supplement containing lactobacilli and bifidobacteria has been shown to reduce the severity and duration of colds.

To supplement, buy a product that contains 1 billion to 10 billion live cells per dose (capsule). Choose a probiotic supplement that contains both lactobacilli and bifidobacteria strains. Children's products are available on the market; these usually contain one-quarter to one-half of the adult dose.


This herb appears to boost the immune system and fight viruses. Some research, although preliminary, even suggests that garlic can help prevent you from catching a cold.

Raw garlic - crushed or minced - seems to work better that cooked garlic. Keep in mind that raw garlic can cause stomach upset and may increase the risk of bleeding in people taking blood thinning medications.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. Her website is