Many Canadians reach for vitamin C, echinacea and ginseng to prevent them from getting a cold or the flu, or quicken their recovery if they've already caught a bug. (Dan Goodman/AP)

Sneezing, coughing, chills and aches. Like it or not, cold and flu season is here, and will be making its presence known to many Canadians until it fizzles out in March or April.

The common cold, characterized by sneezing, runny nose and congestion is quite different from the flu, which includes a sudden onset of fever, headache, muscle aches and exhaustion.

Regardless, they'll both leave you feeling lousy and probably mean missed days at work or school. Healthy Ontario estimates that Canadian adults get an average of four colds a year, while Health Canada says up to 25 per cent of Canadians (that's eight million people) will come down with the flu each year.

Many Canadians reach for vitamin C, echinacea and ginseng to prevent them from getting a cold or the flu, or quicken their recovery if they've already caught a bug. But with little research to support many of these common remedies, the question remains — do they actually work?

Vitamin C

All you have to do is take a look at the shelves of your local pharmacy to see the range of vitamin C products and supplements to know this vitamin is one of the most popular for fighting colds.

Vitamin C has long been believed to play a role in preventing the common cold, however conflicting evidence has brought these claims into question.

The largest study to date, a 2004 Cochrane review of 29 trials involving more than 11,000 participants, found that vitamin C supplements did not actually reduce the number of colds in the general population. However, researchers from the Australian National University who conducted the study found that vitamin C could slightly reduce the duration and severity of colds in people exposed to cold temperatures or extreme physical stress.

Whether or not vitamin C may actually prevent a cold remains to be seen. But it does play a role in wound healing, as well as the maintenance of cartilage, bones and teeth. It's important to meet your daily vitamin C requirement (60 milligrams) through a supplement, or through fibre-rich fruits and vegetables, such as citrus fruits, green and red peppers, berries and tomatoes.

Be wary of high dose vitamin C supplements claiming to defend against cold and flu, though. Vitamin C is a water-soluble vitamin, so your body can only absorb so much before the remainder is flushed out of your system. Excess amounts of the vitamin can also cause diarrhea.

Echinacea

Echinacea, likely one of the most popular herbs on the health market these days, is often used by people who want to prevent the common cold or treat its symptoms. However, like vitamin C, conflicting evidence and media headlines have left many people scratching their heads and wondering if this herb actually works.

One of the latest studies on the subject, published in the July 2007 issue of The Lancet Infectious Diseases, found echinacea could lower the risk of developing a cold by more than 50 per cent and reduce the average duration of a cold by 1.4 days.

However, there is also plenty of evidence to suggest echinacea isn't effective in boosting immunity or preventing colds. One of the most notable studies, published in The New England Journal of Medicine in 2005, found that when echinacea was given to study participants it did not lessen their chances of getting sick.

There isn't conclusive evidence to prove echinacea's effectiveness, but if you do decide to take the herb, be sure to follow dosage recommendations on the bottle.

Ginseng

Ginseng has been used for centuries to treat a variety of ailments. Its reputed benefits include reducing stress, increasing energy, enhancing blood flow and treating Type 2 diabetes. Ginseng use has also grabbed the attention of Canadian consumers because of claims that it boosts immune function.

Of the two main forms of ginseng on the market, Asian and North American, most of the recent research has focused on North American ginseng. While research supporting the claim that North American ginseng can boost immunity and prevent colds is minimal, it's growing, and the findings are promising.

A 2005 Canadian study published in the Canadian Medical Association Journal found that people taking a product derived from North American ginseng called COLD-fx suffered 25 per cent fewer colds compared to those who didn't take the supplement. When participants receiving the herb did get a cold, their symptoms were less severe.

Health Canada recently put its stamp of approval on COLD-fx and its maker's claim that it "helps reduce the frequency, severity and duration of cold and flu symptoms by boosting the immune system."

If you want to take ginseng to help reduce your chances of getting a cold this season, remember there are different kinds of ginseng. Different types can deliver different results, so read labels carefully.

While ginseng is safe for most people, anyone on blood thinners should not take the herb due its anticoagulant effect.

Chicken soup

There's no doubt that a nice homemade bowl of chicken soup can help you feel better when you have a cold. But is there science to back up the age-old advice of eating chicken soup when you're sick?

Believe it or not, a 2000 study published in the journal Chest found that chicken soup might actually have some beneficial medicinal properties due to its anti-inflammatory effect. Another study, also published in Chest, found that eating chicken soup, compared to simply ingesting cold water or hot water, made participants noses run faster — which is a good thing, since this helps rid the body of bacteria.

While these findings are preliminary, a warm bowl of soup can be a good idea when you're sick. It will help you stay hydrated, the hot liquid can help relieve nasal congestion, and it's an easy way to get something nourishing into your body when you don't feel like eating.

Zinc

It's well known that zinc supports a healthy immune system and is needed for wound healing, but can zinc lozenges actually prevent you from getting sick in the first place?

The answer isn't straightforward. Results from studies investigating whether zinc lozenges can prevent a cold, or decrease symptoms, have been inconsistent.

One of the largest studies on zinc, published in the journal Clinical and Infectious Diseases in 2000 and involving more than 500 people, concluded that zinc lozenges had little benefit in treating the common cold.

On the other hand, a study of 100 people published in the Annals of Internal Medicine found participants who took zinc lozenges at the onset of a cold had significantly fewer days with coughing, headache, sore throat and nasal congestion compared to study participants receiving a placebo.

Until further research can prove whether zinc has the ability to act as a cold fighter, it's hard to know if taking it will actually prevent you from getting sick. However, if you've come down with a cold and are willing to try anything, for most people there isn't any harm in taking zinc lozenges as long as you follow the dosage recommendations on the package.

Remember, though, that in most studies supporting zinc's ability to fight a cold, the lozenges were used within 24 hours of the onset of cold symptoms.

The bottom line

The bottom line is that there's no magic pill you can take that will prevent you from getting sick this winter.

In terms of nutrition, your best defence against catching a cold is staying hydrated and eating a healthy, balanced diet that includes protein, whole grains and plenty of fruits and vegetables. By eating a diet that includes a variety of foods you are more likely to meet your vitamin and mineral needs, and that will contribute to your overall health — including a stronger immune system.

And keep in mind that before taking any new vitamin or herbal supplement, it's always a good idea to discuss it with your health care provider.

[an error occurred while processing this directive]