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The Best Defense

12 powerful supplements to supercharge immunity.

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The wear-and-tear of daily living puts an enormous burden on the immune system. Add to that environmental toxins, infectious diseases, and chronic stress, and it’s likely that your immune system could use some support. Whether you’re looking to shore up your defenses before cold and flu season or create long-term immune support to protect against cancer and other diseases, supplements can help. Here are a dozen of the top contenders:

1 Mushroom extracts that contain reishi, maitake and/or shiitake mushrooms are high in beta-glucan, a powerful antiviral agent and immune system modulator. Recent studies suggest that mushroom extracts inhibit tumor growth and protect against cancer. Look for them in capsules that contain combinations of several varieties of mushrooms, as well as other immune-supportive ingredients, or go traditional and brew a tea from whole mushrooms.

2 Zinc is a critical component in the development and activation of T-cells-important players in the immune system-and studies have shown that even mild zinc deficiencies can impair natural killer cell activity and other immune functions. Look for zinc in tablets and capsules for long-term immune support, or in homeopathic lozenges (Zincum Gluconicum, Zincum Aceticum, or other forms) for more immediate relief.

3 Selenium, a mineral found in high concentrations in Brazil nuts and seafood, is a powerful antioxidant that’s been shown to improve immune response. Studies have found that selenium increases the activity of natural killer cells, and deficiencies have been shown to hamper immune response. Look for it in tablets or capsules, as a single supplement, or in combination with zinc, vitamin E, and/or immune-supportive herbs.

4 Elderberry has been used for hundreds of years to fight colds and flu. Like other berries, it’s high in anthocyanins, antioxidants that protect cells from damage and activate the immune response. In one study, elderberry was more effective than echinacea or propolis in activating immune response. Other studies have confirmed the antiviral properties of elderberry, and suggest that taking elderberry can substantially shorten the duration of flu. It may also be effective in treating upper respiratory tract infections. Look for it as an extract or in lozenges, capsules, tablets, and syrups, alone or in combination with other herbs.

5 Cordyceps (Cordyceps sinensis) is a fungus that’s traditionally recommended in Chinese medicine to enhance immune activity and reduce inflammation. It’s used primarily for long-term immunity, and some studies suggest cordyceps has powerful cancer-preventive effects. Cordyceps may also reduce the effects of aging and support memory. Look for it in tablets and capsules.

6 Astragalus is a traditional Chinese herb that’s considered an adaptogen, a compound that helps the body adapt to stress and illness. It’s high in polysaccharides and flavonoids that enhance immune function and help protect against flu. Some studies have also found that astragalus inhibits the development of atherosclerosis and may prevent some kinds of cancer. You’ll find it in capsules or as a tincture, alone or in combination with other herbs such as schisandra or echinacea.

7 Echinacea, also known as the purple coneflower, has been traditionally used for centuries to treat infections and injuries. It’s known for its antiviral and antimicrobial activities, as well as its ability to support immune system function. Though research is mixed, many studies suggest that echinacea reduces the incidence and duration of the common cold. Additionally, it appears to have potent adaptogenic effects, which may offer long-term immune system support. Look for it in capsules, teas, lozenges, or standardized extracts, either alone or in combination with goldenseal, green tea, astragalus, or other immune boosters.

8 Pelargonium sidoides, also known as African geranium, is an herbal extract that has powerful antimicrobial, antiviral, and immunomodulatory effects. Pelargonium also acts as a natural expectorant to dispel excess mucus, and is especially effective at treating bronchitis, sinusitis, and other respiratory infections. It’s also called umckaloabo and sold under the brand name “Umcka” for short. Look for it as a standardized extract, or in capsules, tablets, syrups, and chewables.

9 Olive leaf extract- from the leaves of the olive tree (Olea europaea)-has been used for many years as a traditional treatment for colds, flu, and infection. It contains a compound called oleuropein, which has antibacterial, antiviral, and anti-inflammatory properties. Olive leaf extract may also inhibit replication of HIV-1, the virus that causes AIDS. Look for it in capsules or as an extract.

10 Probiotics are one of the safest, most effective therapies for long-term immune system support. They’re especially effective at preventing and treating infectious diarrhea, as well as diarrhea associated with antibiotic use. Studies suggest they can also protect against cancer. Look for them in capsules, liquids, or chewables, as single strains or as a broad-spectrum blend of varieties.

11 N-acetyl cysteine (NAC), from the amino acid L-cysteine, is used by the liver to form glutathione, a powerful antioxidant that’s critical for immune health. NAC is especially important for anyone who has liver problems, since a compromised liver is unable to produce adequate glutathione. Studies have demonstrated NAC’s ability to regulate and enhance immune-system activity. Look for it in capsules and tablets, alone or in combination with antioxidants, herbs, and other immune-supportive ingredients.

12 Larch, from the wood of the Western larch (Larix occidentalis), is high in arabinogalactan, a polysaccharide that enhances immune response to viral and bacterial infection. In studies, larch helps defend against the common cold, and it also shows promise as a cancer preventative. Find it in capsules, powders, or liquids, or as a flower essence.

Editors’ Product Picks
Here are five of our favorite supplements for fortifying the immune system and relieving cold symptoms:

Barlean’sOlive Leaf Extract is made with only fresh-picked olive leaves to ensure the full spectrum of active constituents remains intact.

Mushroom WisdomMushroom Emperors multi-mushroom formulation blends potent, standardized extracts from a variety of species.

Nature’s WayUmcka ColdCare Soothing Syrup (Cherry flavor) with Pelargonium sidoides has been shown to help shorten the duration of colds and ease symptoms.

North American Herb & Spice Lovely-Larch Tea boosts immunity with every sip. Sweeten with
honey if desired.

Source NaturalsWellness Formula combines zinc, selenium, olive leaf, echinacea, and several other proven immune boosters in one great formula.

5 Immune Busters
In addition to boosting your natural defenses with the right nutrients and herbs, the best way to stay healthy is to steer clear of anything that puts an undue burden on your immune system. Here are 5 common culprits to avoid:

1. Excess Calories. In one recent study, restricting calories by 10 percent improved immune function. And overall incidence and severity of specific types of infectious illnesses are higher in obese people.

2. Sugar. To put it simply, sugar suppresses immune function. In one study, drinking 24 ounces of sugary soda depressed the activity of white blood cells that fight infection by 50 percent. Honey and orange juice have similar effects.

3. Allergenic foods. Food allergies and sensitivities suppress immune function by creating chronic, underlying inflammation in the body. Avoid common allergens such as wheat, dairy, soy, and corn, and if you suspect that you may have sensitivities, get tested.

4. Late Nights. Sleep deprivation can have a negative impact on immune function. Studies have shown that lack of sleep leads to a decrease in T-cells activity and an increase in inflammatory cytokines.

5. Stress. Too much stress leads to chronically high levels of cortisol, which can have immunosuppressive effects over time. So chill out. Studies show that stress management techniques such as progressive muscle relaxation and guided imagery lower cortisol levels.