vitamin C, take echinacea or zinc, or heat up some chicken soup. And they may
mention that taking their secret remedy before the first sniffle may have
helped you avoid the cold altogether.
Never mind the fervor with which these cold remedies are offered. Do they
actually work? WebMD turned to three top experts who have studied the cold
virus for decades.
First, the really bad news: "You can't cure a cold," says David A.
Blandino, MD, chairman of family and community medicine at the University of
Pennsylvania Medical Center Shadyside Hospital in Pittsburgh.
But you may be able to shorten one. Here's the scorecard on whether natural
cold remedies such as vitamins and supplements get a thumbs up or
Natural Cold Remedies: The Rundown
1. Zinc. The mineral zinc, available in over-the-counter lozenges,
nasal sprays, and gels, may work by preventing the formation of proteins needed
by a cold virus to reproduce.
Despite the hoopla about zinc for treatment of colds, scientific studies are
scarce, says Jack M. Gwaltney, MD, professor emeritus of internal medicine at
the University of Virginia and a longtime cold researcher. Gwaltney tells WebMD
that he and his colleagues could find only 14 published studies that looked at
zinc the scientific way, with both placebo and treatment groups. Zinc lozenges,
they conclude, have no effect. One well-designed study reported a positive
effect on treating a cold with zinc nasal gel. But the study results have not
yet been replicated, Gwaltney says.
2. Vitamin C. For decades, believers in vitamin C have said taking
this vitamin supplement can nip a cold in the bud. The claim is partially
triggered by lab studies that find vitamin C affects resistance to virus in
But in people? Experts disagree on this slightly but lean toward the
negative. Some, including Blandino, say vitamin C has not been proven to
shorten the duration of a cold. One 2007 study showed that if vitamin C is
taken after a cold begins, it doesn't shorten the cold or make it less severe.
But when it is taken daily as a preventive treatment -- not just after that
first sniffle -- it can very slightly shorten cold duration, by about 8% in
adults and by about 14% in children.
Very highly fit people -- marathon runners, for instance -- might cut their
risk of a cold in half by taking the vitamin, the study also showed.
But Gwaltney does not agree. "The weight of scientific evidence and the
well-done studies indicate vitamin C does not prevent colds," says
Gwaltney. "It may have some mild effect on treating colds ."
3. Echinacea. The herbal supplement echinacea, like Vitamin C, sparks
controversy among cold experts. Advocates say it's an immune booster with
antiviral properties and other benefits, so it's good at preventing colds . However, two
recent studies on the natural remedy have yielded conflicting conclusions. In
one 2007 study, University of Connecticut researchers concluded that echinacea
decreases the odds of developing a cold by 58% and reduces its duration by 1.4
days. But a previous study, conducted by Gwaltney's colleagues at the
University of Virginia and published in 2005 in The New England Journal of
Medicine, showed no benefit from the herb in either reducing the severity
of a cold infection or preventing a cold.
Echinacea drew a "no" vote from our three experts -- Gwaltney,
Blandino, and Owen Hendley, MD, professor of pediatrics in the division of
infectious diseases at the University of Virginia, Charlottesvile.
4. Chicken Soup. Advocates of hot chicken soup, long offered as a
cold remedy, say it may help soothe inflammation that can make the symptoms worse.
The problem with proving scientifically that chicken soup works, says
Gwaltney, is finding a legitimate placebofood to study against it in a
scientific way. "We were contacted by a soup manufacturer to do a study on
chicken soup," he tells WebMD. "We thought we could use another hot
beverage" for placebo, he says. "But it's got to look, smell, and taste
[like chicken soup]." They didn't find anything that measured up.
Gwaltney calls chicken soup "a waste of time."
That's despite the well-publicized report published in 2000 in which
researchers reported that chicken soup, which they studied in the laboratory,
may have an anti-inflammatory effect on easing symptoms of upper respiratory
infections. But the report doesn't prove chicken soup does anything for cold symptoms , Gwaltney says,
because it didn't include a test of people nor include a placebo for
Although chicken soup may not actively fight a cold, it can help fight dehydration that can occur when
you have a cold or the flu.
Preventing a Cold: Does Anything Really Work?
Hand washing has long been touted as a way to prevent a cold during cold and
flu season, and experts agree that is wise.
But here's the newest twist: Paying attention to where you put your hands --
and scheduling your hand washing around where your hands have been, rather than
the clock -- appear to be important, too. That's because cold viruses may
linger on surfaces longer then suspected, Hendley and his colleagues have
Hendley and other University of Virginia researchers did a study published
in 2007 of people with a cold who stayed overnight in a hotel. "We went in
the next day and swabbed 10 sites they had touched," Hendley says.
"We found about 30% or 40% of the sites had virus on them." He's
talking about surfaces such as light switches and TV remote controls. "A
third of the time, the virus was still there," Hendley says of the site
samples. "Now we are trying to figure out, is it still infectious?" The
hotel study didn't go there, but that study is under way.
Until more research is in, Gwaltney suggests hand washing after touching
potentially germy surfaces, rather than adhering to the often-suggested advice
of hand washing throughout the day no matter what you've touched.
Rhinoviruses cause about half of all colds in adults, Hendley says. You
acquire the virus by getting it on your hand and then touching your nose or
eyes, he says. "The virus doesn't usually go through the air," Hendley
says. "You usually get it on the finger and you inoculate yourself. Just
being in the air space [with an infected person or the virus] is not
Besides hand washing, breathing in humidified air and increasing your fluid
intake may also help, Blandino says.
Whatever natural remedy you use, the effects on the cold will be minimal,
cautions Gwaltney. Of natural cold remedies, he says: "They're not as
effective as commercial cold remedies" such as decongestant,
antihistamines, and nonsteroidal anti-inflammatory drugs .
Patience could pay off, too, Blandino says. "You can't cure the
cold," he says. "[But] most of them are gone within 10 days."
By Kathleen Doheny
Reviewed by Louise Chang
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