|
|
We consider it quite a feat to escape winter without a single cold.
However, research is beginning to indicate that a healthy diet may
help strengthen the immune system and give your body the best chance
of fighting colds.
To date, the only specific cold treatments available from your doctor
or pharmacist are designed to deal with symptoms such as sore throats,
runny or stuffy noses, coughing, sneezing and sleeplessness. Very
little advice is given on diet for the simple reason that there is
little research-based evidence to suggest that what you eat has much
effect once the virus has taken hold.
One possible exception to this rule is increasing intakes of vitamin
C.
Although not yet conclusive, the indications are that giving people
large quantities of this nutrient the moment that cold symptoms appear
may be of some benefit. It has been found that for some people, taking
between 500 -1000mg of vitamin C a day could help to lessen the severity
and possibly the duration of a cold. Researchers feel that these effects
could be due to the vitamin C in the blood boosting interferon levels
thus helping to protect cells from viral attack.
Vitamin C intake can be increased through foods and drinks such as
citrus fruits and juices, kiwi fruit, sweet potatoes, peppers, blackcurrants,
green leafy vegetables and exotic fruits, such as guava, or certain
foods fortified with vitamin C. Supplements of vitamin C may also
be considered.
Other work indicates that prevention could well be better than cure.
When elderly people in long-term care were given a multi-micronutrient
supplement including 20mg of zinc, 100µg of selenium, 15mg of vitamin
E and 6mg of beta carotene, scientists discovered that they caught
fewer respiratory infections. It is possible that diets supplying
good and regular amounts of these vitamins and minerals could help
to protect the population at large.
It is not just vitamins and minerals that are potentially important
infection fighters. Herbalists have long promoted the benefits of
garlic for its antiviral effects; a property that could be due to
a natural constituent it supplies. Extracts from Echinacea, (the purple
cornflower), as drops or capsules are also valued for their antiviral
effects. Just as certain nutrients seem to help strengthen the immune
system, stress appears to deplete some vitamins and minerals. Combining
a healthy varied diet containing a lot of fruits and vegetables with
a good balance of exercise and sleep would seem to be a good strategy
to start this winter's battle against the common cold.
Foods supplying Vitamin C, Vitamin E, Beta Carotene, Zinc and Selenium
Nutrient Foods to Eat
- Vitamin C: Citrus fruits, kiwi, guava, peppers, blackcurrants,
strawberries
- Vitamin E Almonds, hazelnuts, sunflower seeds, sweet potatoes,
sunflower oil, wheat germ and wheat germ oil, avocado pears
- Beta carotene Carrots, sweet potatoes, pumpkin, guava, mangoes,
apricots, red peppers tomatoes, dark green vegetables
- Zinc Shellfish, red meat, wheat germ, whole grain cereals like
wholemeal bread and whole grain breakfast cereals
- Selenium Brazil nuts, sunflower seeds, mussels, tuna canned in
oil, haddock, kidneys.
Sources
Eufic 1999
Paul Knipschild: Systemic Reviews: Vitamin C and the common cold. BMJ;
309:719-21, 1994 . Carr AB et al:
Vitamin C and the common cold: Using identical twins as controls. Med
J Aust 2:411-12, 1981. Gerber WF et al:
Effect of ascorbic acid, sodium salicylate, and caffeine on the serum
interferon level in response to viral infection.
Pharmacology 13 (3): 228-33, 1975. Mary Ann Johnson et al: Micronutrient
Supplementation and Infection in Institutionalized Elders, Nutr Re,
vol. 55, No. 11, 400 - 404. Berdanier CD: The many faces of stress,
Nutr. Today 22 (2): 12, 1987. Ross AC: Vitamin A and protective immunity,
Nutr Today 27 (4):18, 1992
 |
|
