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Ever wonder why some of us fall constant prey to seasonal colds and flu, while others waltz through winter without so much as a sniffle? If you find yourself among the bed-ridden, you can certainly lay some blame on the fact that viruses thrive in cold, damp conditions. Your body, meanwhile, must adapt to winter’s climatic changes at a time when you’re spending your days mostly indoors in close contact with others.

But that still doesn’t answer the question you’re probably pondering: Why me? Compelling new research has some scientists now arguing that colds and flu aren’t just a simple matter of viral exposure. A recent study at UCLA revealed that subjecting healthy people to someone contaminated with a cold for 48 hours did not give the healthy subjects a cold. The conclusion? Colds result not from a cold virus, but from “an internal disturbance of the body’s immune system,” according to the researchers.

Before figuring out how, in addition to yoga, you can bolster your defenses, it helps to understand what you’re dealing with—and how your body defends itself. Colds and flu wreak havoc in different ways. The common cold may be caused by a number of viruses, some of which can lead to secondary bacterial infections such as bronchitis, strep throat, and pneumonia. Cold viruses inflame the mucous membranes lining the upper respiratory system. The flu virus, on the other hand, comes in three different strains and infects the entire respiratory tract. The flu, therefore, has a higher capability of leading to serious complications.

As you probably know first-hand, colds and flu quickly throw a well-ordered immune system into chaos. But while the prevailing onslaught of symptoms (coughing, sneezing, congestion, runny nose) may be uncomfortable, they signal a counterattack being waged by the body against the viral intruder. As William Mitchell, N.D., explains, the body tries to make life unpleasant enough for a virus or bacteria that it will want to leave. “The body does this in a number of ways,” he says. “It withholds iron so that microbes can’t use it to fuel up; excretes free radicals; raises the temperature; slightly changes the pH balance in tissues; and engulfs a microbe through a process called phagocytosis.”

The immune system is an elaborate communication network of defensive and offensive cells. At the helm are lymphocytes, a type of white blood cell that includes B cells and T cells. B cells produce antibodies that act like a stun gun to neutralize invading antigens in preparation for T cells to finish them off. Both keep an endless watch throughout the body. “Helper” T cells coordinate attacks on invaders, while “suppressor” T cells call the cease-fires.

T cells secrete proteins like interferon, which boasts antiviral properties. Meanwhile, the offensive is comprised of cells called macrophages that circulate in the blood and scavenge for foreign antigens in a perpetual search-and-destroy mission. Macrophages engulf unwanted bacteria, then destroy them with enzymes called lysosomes that they secrete.

Every one of these immune-system members performs a vital function in protecting the body—and they depend on teamwork to achieve their individual goals. B cells, for example, require T cells to recognize an intruder and then give them the go-ahead to generate the necessary antibodies. Likewise, just as in a real-life military outfit, a hole in the defense line can lead to a losing battle. For example, if lymphocytes are compromised by stress or a nutrient deficiency, everything else down the immune line can also malfunction.

Each of the resulting symptoms we experience has a healing or detoxifying function. Sneezing, for example, keeps the virus up and out of the lungs, while the increase in mucous secretions carries immunoglobulins to wash out toxins. That’s why holistic care practitioners counsel people against cold and flu medicines that work by suppressing symptoms, such as decongestants, cough syrups, and antipyretics (acetaminophen). While alleviating temporary discomfort, they inevitably prolong the illness by tampering with the body’s process of self-healing.

Cold and Flu Insurance

If you’re looking for a way to bolster defenses, natural remedies are a good place to start. Herbal treatments work as immunotonics to help reinforce, balance, and strengthen the immune system. Some herbs prevent infections while others stop an infection or speed recovery.

For example, a regimen of either Siberian ginseng in doses of 500mg three times a day, or 1,000mg daily of the amino acid lysine, can have a general antiviral, tonifying effect that fortifies the immune system. Chinese astragalus root, recently spotlighted in clinical trials, stimulates every phase of immune function. It increases the number of stem cells (the parent cells of all bodily tissues) and helps them develop into active immune cells, significantly enhancing macrophage activity, and consequently reducing the number and duration of colds.

Other more popularized treatments such as echinacea activate T cells and macrophages, improve antibody binding, increase the circulation of white blood cells, and enhance killer T cell activity. Study findings reported by the Herb Research Foundation show that echinacea can even increase phagocytosis (the consumption of invading organisms) by 20 to 40 percent.

Meanwhile, homeopathy, which is based on the principle of “like cures like,” features remedies made of super-diluted extractions from plant, animal, or mineral substances.

This treatment relies on the paradox that many substances, when taken full-strength or in a natural form, evoke the very symptoms they allay in a homeopathic dose. (For instance, a homeopathic dose of poison ivy will relieve the itching and burning caused by contact with the plant.) In the homeopathic view, explains Kathleen Fry, M.D., “Some people are more prone to infections because they are said to have a weak vital force, which is prana in Ayurvedic medicine, or chi in traditional Chinese medicine. In such cases, they need a constitutional homeopathic treatment to fortify their immune system.” In terms of individual remedies, though, Fry suggests using gelsemium (yellow jasmine) for flu symptoms, “especially if you’re achy, anxious, or have weakness,” or a homeopathic dose of the otherwise toxic sulfuric acid for a sore throat. Homeopathic colds and flu kits are also available at health food stores.

Aside from homeopathic remedies, you have other natural means of symptom relief at your disposal. For a sinus infection, place a hot water bottle covered with a castor oil-soaked cloth over the sinus area for 20 to 40 minutes. For respiratory infections, try licorice, which has antiviral properties. Or try a soothing mix of licorice root, gum weed, and bloodroot for a dry cough and sore throat.

A Dose of Common Sense

A cupboard full of cures will only take you so far in your search for good health, however, since lifestyle habits also play a crucial role. Think of pumping supreme gasoline into your car but not maintaining or repairing the vehicle in any other way. Consider herbs and homeopathic medicine your reinforcements, while your living choices lay the foundation for strong viral resistance.

You’re probably already acutely aware of the immune-compromising effects of stress, for instance. Stress in the body triggers the release of hormones from the adrenal glands, namely cortisol, which cause the thymus (the major immune-system gland) to shrink. This precipitates a cascade of events that suppress immune functions. At Ohio State University, researchers found that subjects who were more reactive to stress, such as medical students at exam time or those caring for a spouse with Alzheimer’s, had a diminished immune response to inoculations of Hepatitis B and the influenza virus than their peers.

Sleep deprivation can yield similar harmful health consequences. According to the National Sleep Foundation, research suggests that sleep is associated with immune function—especially deep sleep or the non-REM phase of sleep, when immune-enhancing hormones such as interleukin-1 increase in production. One study showed that sleep loss decreased the rate of phagocytosis and the production of lymphocytes (a type of white blood cell).

Diet also weighs in the equation, since sugar, caffeine, alcohol, and fat all suppress various immune functions. Sugar reduces the ability of neutrophils to engulf and destroy bacteria, and compromises lymphocyte activity. Increased serum levels of cholesterol and triglyceride can compromise antibody production. Caffeine and alcohol raise stress levels; alcohol depletes vitamins C and B6, which the body particularly needs in times of infection. You should also avoid peanuts and chocolate during the cold and flu season since these contain arginine, a component that encourages viral growth.

And perhaps most important, according to the American Council on Exercise, physical activity increases natural killer cell activity. Even one bout of exercise can boost immune function for several hours afterwards, and this short-term boost appears to reduce risk of infection in the long term. All of this makes it clear that when it comes to colds and flu, the best offense is a good defense. Granted, some viruses will prevail despite your best efforts. But by integrating the elements of healthy living into your daily life, you can achieve a balance between mind and body that enriches immune function. And maybe this winter, you’ll be the one sailing through with nary a sneeze or a sniffle.

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