The question: Do certain foods and supplements help treat a cold?
The answer: This is a timely question, considering that I'm currently fighting a nasty cold – my first in years. It began as a scratchy sore throat, then came the congestion, runny nose and mild fever.
If that sounds familiar it's because this is the time of year when many people come down with the common cold. The cooler weather keeps us indoors where we're more likely to come into prolonged contact with people who are infected (I blame 10 hours on an airplane for my miserable symptoms).
The good news: Growing evidence suggests that certain foods and supplements can ease cold symptoms, albeit modestly. The following remedies might be worth a try. (If you are pregnant, have a medical condition or take medication, speak to your doctor before taking any natural health product.)
Hot fluids. When you have a cold, be sure to drink plenty of hot liquids, such as hot water, tea, soup and broth to relieve nasal congestion and prevent dehydration. Fluids also keep the lining of the upper respiratory track moist, which can ease sore-throat symptoms.
Chicken soup. According to researchers from the University of Nebraska, there is scientific validity to the age-old notion that chicken soup treats a cold. A homemade chicken soup – containing chicken, onions, sweet potatoes, parsnips, turnips, carrots, celery, parsley, salt and pepper – was shown to dampen the activity of white blood cells that trigger inflammation. Slowing the activity of these white blood cells is thought to reduce the flow of mucus in the lungs and nasal passages.
Vitamin C. Most research shows that taking 2,000 milligrams of vitamin C per day (divided as 500 milligrams four times daily) decreases the duration of a cold by 24 to 36 hours. Vitamin C might not work for everyone, however. The nutrient seems to be most effective in children, in people whose diets contain little vitamin C and in those under physical stress (such as marathon runners or physical labourers).
Zinc lozenges. Many studies have revealed that taking zinc gluconate or zinc citrate lozenges, started within 24 to 48 hours of the onset of symptoms, reduces the severity and duration of cold symptoms. Zinc may block the replication of cold viruses in the upper respiratory tract.
Most zinc lozenges contain 10 milligrams of zinc. Do not take more that 50 milligrams of zinc per day (one lozenge every two hours); too much zinc can actually depress the immune system.
Probiotics. In adults and kids, taking a daily supplement of these "friendly" bacteria has been shown to reduce the severity and duration of colds, presumably by stimulating the immune system.
Buy a product that contains both lactobacilli and bifidobacteria, the two main types of probiotic bacteria. Take one to 10 billion live cells per dose. Children's products typically contain one-quarter to one-half the adult dose.
Of course, prevention is the key to staying healthy this fall and winter. Your first line of defence is adequate sleep – sleep deprivation disrupts the immune system – and good personal hygiene. Cold viruses can live for hours on surfaces such as door handles, keyboards, phones and a drinking glass, so frequent hand-washing is paramount to warding off colds.
Bolstering your body's immune system by getting regular exercise and ensuring your diet includes adequate protein and plenty of fruit and vegetables are also keys to preventing the common cold.
Leslie Beck, a registered dietitian, is based at the Medisys clinic in Toronto. She can be seen every Thursday at noon on CTV News Channel's Direct ( www.lesliebeck.com ).
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