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Boost Immunity

Arm yourself for cold and flu season with these natural lifestyle and supplement tips.

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According to the Centers for Disease Control and Prevention, about one-third of adults older than 60 may have antibodies against the H1N1-flu virus.

As if a run-of-the-mill flu season weren’t bad enough, we now have to contend with the threat of H1N1 or “swine flu.” How do we survive and even thrive in this world that is teeming with microorganisms? The answer, in short, is our immune system. Composed of millions of cells circulating throughout the body, this system protects us by fighting off microscopic enemy invaders such as bacteria, viruses, toxins, fungus, and parasites. Keeping the immune system in top fighting form requires improvements in lifestyle and diet. And we can further enhance its functioning with the right dietary supplements.

Lifestyle Matters
When we are exposed to stress, our levels of a hormone called cortisol can become chronically elevated, suppressing immune activity. Therefore strong immune function depends on an effective stress-reduction program. Strategies such as relaxation exercises, hypnosis, exercise, biofeedback, yoga, and meditation have been shown to reduce both stressful feelings and to improve immunity.

Adequate sleep is also essential for proper immune system function. Sleep-deprived individuals have decreased natural killer cell activity and decreased cellular immunity. Even a few nights of sleep deprivation can disrupt immune function. While no one knows with certainty how much sleep is ideal, the general consensus is that most individuals need between seven and nine hours of sleep nightly.

Daily physical activity is linked with increased immune activity as well. Exercising for 30 to 60 minutes daily will improve overall conditioning over time. Exercise should include both aerobic (such as walking, jogging, swimming, bicycling, basketball, dancing, or tennis) and anaerobic (such as weight lifting, yoga, or Pilates) activities.

If you smoke, or overindulge in alcohol, your immune system is more likely to be impaired.

The good news is that when smokers quit, their immune function improves dramatically and quickly. Within just one month of quitting, previous smokers demonstrate increased natural killer cell activity and elevations in antibody levels. Within two weeks of abstinence from alcohol, previously depressed cellular immunity improves. Within two months of sobriety, cellular immunity normalizes.

A Defensive Diet
Just like any of our bodily processes, our immune system relies upon good nutrition to function at its best. Creating a rainbow of color on your plate is one of the best ways to build a healthy immune system. By eating a wide variety of colorful fruits and vegetables, you are consuming a full spectrum of antioxidative flavonoids. In addition to flavonoids, fruits and vegetables contain important immune-enhancing vitamins and minerals. These nutrients include zinc, vitamin E, vitamin D, sterols, and carotenes such as vitamin A and lycopene. Fill your plate with zinc-rich oysters, pumpkin seeds, and almonds; vitamin E-rich wheat germ, sunflower oil, and spinach; dietary plant sterols (such as unrefined oils, nuts, seeds, and grains); and free radical-scavenging carotenes found in dark green vegetables, carrots, yams, and tomatoes. Be sure to obtain daily safe sun exposure for adequate vitamin D, and eat vitamin D-rich foods, such as cod liver oil, sardines, salmon, mackerel, and tuna.

Fat is also an essential nutrient. Unfortunately, most of us eat too much fat and the wrong kind of fat. Excess fat in the diet is stored and leads to obesity, which is associated with significant immune impairment. Fat should comprise no more than 30 percent of total daily calories. Saturated fats and trans fats are unhealthful and should be avoided. Better choices are polyunsaturated and monounsaturated fats found in vegetables and nuts and their oils. Certain fats are considered essential fats, or essential fatty acids (EFAs). Fish, especially sardines, salmon, cod, and halibut, is an excellent source of omega-3s (EPA and DHA). Omega-3 EFAs are critical to strong immune function.

No discussion of diet and immunity would be complete without mentioning sugar. Glucose, fructose, sucrose, and any other form of sugar impair lymphocyte activity, which is essential for immunity. The average person consumes 150 g of sucrose every day. This means that most people are suppressing their immune systems by consuming sugar. If we simply decreased our sugar intake, we would experience a major decrease in colds, flu, and other infections.

In addition to the vitamins, minerals, and other nutrients that have been shown to elicit a positive immune response, there are some excellent immune-stimulating supplements and herbs you can add to your immunity arsenal:

Coenzyme Q10: Also known as ubiquinone, CoQ10 is potent antioxidant nutrient that enhances cellular production of energy and immune function. It supports antibody production, phagocytic activity, and is especially necessary during active infection.

Astragalus: Astragalus root has demonstrated antiviral properties against a wide array of viruses, including the adenovirus, parainfluenza and hepatitis B.

Echinacea: Perhaps the most widely used herb for supporting immune function, echinacea stimulates the activity of macrophages (natural killer cells) and lymphocytes, and scavenges free radicals.

Garlic: Garlic has strong antimicrobial activities against bacteria, viruses, fungal organisms, and parasites. Aged garlic extract increases B cell antibody production, as well as the activity
of macrophages, T cells, and natural killer cells.

Mushroom polysaccharides: Components in this common food stimulate cytotoxicity, important for cancer-cell death. Mushroom extracts also exert direct antitumor activity and block the signals that cancer cells use to develop a blood supply.

Probiotics: Beneficial bacteria in the intestines activate immune cells, increase natural killer cell activity and are necessary in our fight against disease-causing bacteria.

Product Examples (from left)

Nature’s Way Umcka Cold + Flu Berry Flavor Chewables contains pelargonium, an herb that has a powerful effect against cold and flu symptoms

NOW Foods Immune Renew has a healthful dose of astragalus, a powerful immune system booster.

Source Naturals Wellness Flu Guard is a comprehensive homeopathic flu remedy that reduces the duration and severity of flu symptoms.

Flora Dr. Dunner Sambu Guard for Kids contains elderberry, a wonderful herb for both preventing and treating the flu and other viruses. Research supports its use as a flu remedy.