Doctors and scientists have worked long and hard to find a cure for colds and flu. Recent advances have given us the flu vaccine and the anti-flu medication Relenza (zanamivir). However, stocks of the flu vaccine are running dry, and Relenza is only recommended for those over the age of 65 or with significant illness. Plus, neither of these treatments is designed to combat the common cold, a condition which affects pretty much the whole population at least once a year. Despite some promise, it still appears as though conventional medicine has little to offer in terms of protection from cold and flu. Fortunately, natural approaches can be very effective in keeping winter infections at bay. There is a wealth of scientific evidence to suggest that certain vitamins, minerals and herbs can help combat the viruses responsible for cold and flu, and often do much to prevent and speed recovery from these infections.

Our susceptibility to infection is essentially dictated by the efficiency of our immune system – the part of the body responsible for repelling unwanted organisms such as viruses and bacteria. The strength of the immune system is intimately related to lifestyle factors, including what we eat. An important dietary component in this respect is sugar. Two studies dating from the 1970s published in the American Journal of Clinical Nutrition show that sugar has the capacity to disable the immune system. It therefore makes sense to limit sugar and probably refined carbohydrates (such as white bread and other white flour products) if we want to give our immune system the best chances of successfully fending off infectious agents. While many of us are tempted to load up on orange juice at the first sign of a cold or flu, I would question the wisdom in this. While the vitamin C in orange juice may help fight the infection in theory (see below), the amount contained in commercially produced orange juices is very small compared to what appears to be the effective dose. Plus, the high sugar content of these juices are likely to impair immune function, and may therefore prolong the infection rather than shorten it.

Several natural agents have been found to be effective in treating the common cold, probably the best known of which is vitamin C. Vitamin C has several immune strengthening and anti-viral actions in the body. Most studies suggest that 1.5 - 4 g of vitamin C taken in divided doses during the day at the first sign of a cold reduce number of ill days by about 30 p.c. In accordance with the work of late Linus Pauling, an ardent proponent of vitamin C, many people find larger doses more effective. Taking 1 – 2 g of vitamin C every two waking hours until a day or two after the symptoms disappear often seems to stop a cold or flu in its tracks. This large dose of vitamin C can sometimes cause some loosening of the bowels, though this side effect resolves once the dose is reduced.

Another useful nutrient for combating the common cold is zinc. Zinc inhibits the virus responsible for the cold infections (rhinovirus). A study published in 1984 in the journal Antimicrobial Agents and Chemotherapy found that sucking a zinc lozenge every two waking hours reduced the average duration of colds by seven days compared to placebo (inactive medication). The precise form of the zinc in the lozenge is important – it should be zinc gluconate. Other forms of zinc may not actually liberate sufficient quantities of zinc to exert a significant effect. The lozenge should not contain citric acid, tartaric acid, mannitol or sorbitol either, as these can inactivate the zinc. I will warn you; zinc lozenges taste awful. However, in my experience, most individuals will put up with the taste because the benefits of this treatment are usually so clear.

The herb echinacea has gained quite a reputation over the last few years as a potent infection fighter. Echinacea has proven immune stimulating activity, and a review in the Journal of Family Practice last year concluded that there was good evidence to support its use in the treatment of the common cold. There are two main species of echinacea used therapeutically – purpurea and angustifolia. Purpurea is the type most commonly found in health food stores, but angustifolia certainly has merit and contains anti-viral agents called echinacosides which are not found in the purpurea plant. Because of this, for maximum effect, I always suggest my patients use a blend of both types of echinacea. ‘Echinaid’ is a new range of echinacea products which includes tablets and tinctures containing both purpurea and angustifolia forms. You will find Echinaid in independent health food stores.

Another useful agent in the treatment of viral infections is Sambucol. This product contains a blend of black elderberries (Sambucus nigra L.) and raspberries (Rubus idaeus L.) which have the ability to inhibit the flu virus. One study presented at the International Congress of Infectious Diseases in 1994 found that if Sambucol is started within 24 hours of the onset of symptoms, 90 p.c. of subjects became symptom-free in 2-3 days. In contrast, individuals taking inactive medication did not recover for at least six days. Sambucol is available in independent health food stores.

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