It’s no surprise that with fall and winter come a spike in colds and flus. Although you can’t do anything about the weather, you can help your immune system adjust to it so it can protect you 24/7 from bacteria, viruses and other “foreign” invaders that enter through your skin, airways or digestive system.

Your body fights invaders in two ways: innate immunity (physical barriers, such as skin, stomach acid, mucus) and adaptive immune responses (antibodies and specialized blood cells). Healthy immune function often suffers when we eat too many processed foods, especially refined sugar, or when we encounter environmental toxins, says Sheila Kingsbury, N.D., R.H., and chair of botanical medicine at Bastyr University in Kenmore, Wash. Fortunately, there are many ways to strengthen immunity, too.

Ample rest and exercise, and eating a well-rounded diet with plenty of antioxidant-rich fruits and vegetables—especially those with deep color, such as berries, dark leafy greens, and red and orange root vegetables—help keep your immune system in tip-top shape. Also, Kingsbury recommends these supplements for extra immune support to carry you healthfully through the change of seasons.

Probiotics

According to research, healthy gut microflora (bacteria)—also known as probiotics—regulate the immune response and help the body resolve problems faster, Kingsbury says. These helpful bacteria fight off bad bugs and viruses, and keep inflammation in check, another plus for immunity because inflammation is the
body’s normal response to injuries or infections.
How to take: Opt for probiotic-rich foods, such as yogurt or kefir with “live and active cultures,” sauerkraut, tempeh, miso and fermented nondairy beverages—plus prebiotic fiber in plant foods, such as roots and green leafy vegetables, which helps probiotics flourish. Add in probiotic supplements during and after illness.
Look for: Certain probiotic strains will likely work better for your particular body than others. It may take some trial and error, Kingsbury says. Opt for refrigerated products clearly labeled with specific strains; talk to the expert at your store about what’s right for you. Try Nutrition Now PB 8, a proprietary probiotic blend at a good introductory price.

Elderberry

The dark, round berries of the Sambucus nigra plant have been used for centuries to treat respiratory illnesses, partly because they contain anthocyanin, a potent antioxidant. “Elderberry has antiviral properties, tones the immune system and supports healthy mucous membranes,” Kingsbury says. “This is a safe, adaptable remedy.”
How to take: Kingsbury recommends a teaspoon of syrup throughout cold and flu season to beef up the immune system. If you get ill, increase the frequency to 3–4 times per day.
Look for: Honey-, sugar- or glycerin-based elderberry syrups; elderberry lozenges and teas; and elderberry as a component of complementary herb mixtures. Do not give honey-based syrups to infants 12 months or younger. Well-known brands with elderberry products include Nature’s Way and Gaia Herbs.

Learn more about elderberries.

Astragalus

A popular herb in traditional Chinese medicine, astragalus battles bacteria, viruses and stress. “I recommend this herb particularly for people who get more than four to six colds per year,” Kingsbury says. Initial research on the herb shows that astragalus may work by stimulating and bolstering the immune system.
How to take: To reach full efficacy, astragalus should be taken for three to six months in tincture or glyceride form. Take 1 teaspoon per day for prevention, more if you’re feeling sick. For adults, Kingsbury recommends astragalus in combination with eleuthero (Siberian ginseng), at ½ to 1 teaspoon per day. Take eleuthero only in the morning because it can have a stimulating effect similar to caffeine.
Look for: Well-known brands, including Nature’s Way and Herb Pharm, with independently verified ingredients.

Mushrooms

In recent research, medicinal mushrooms—such as reishi, shiitake and turkey tail, among others—have been found to stimulate white blood cell production and boost immunity. The betaglucans in most mushrooms strengthen the immune system, and mushrooms’ polysaccharides modulate immunity. “Mushrooms
are good for long-term and major episodes of illness, from colds to cancer,” Kingsbury says.
How to take: Mushrooms are most easily taken in capsules. Take 1–4 capsules per day, depending on the severity of illness. Mushrooms are safe to take long-term.
Look for: A combination of mushroom species, such as those available from Host Defense’s Stamets 7 and MyCommunity.

Find a medley of healthy, tasty mushroom recipes here.

Omega-3 Fatty Acids

Long revered for anti-inflammatory effects, omega-3s also balance the immune system, increasing or reducing immune response as needed. In one
recent study, mothers who consumed 400 mg DHA (a popular omega-3) during pregnancy significantly reduced the likelihood that their children would catch colds during the first month after birth.
How to take: For general immune support, supplement with a 1,000-mg omega-3 fatty acid combination daily. Kingsbury recommends 1 tablespoon of cod liver oil, for example.
Look for: Fish oil supplements containing at least 300 mg EPA that are independently verified free of mercury and other contaminants. Try Nordic Naturals’ Ultimate Omega items or Barlean’s Swirl oils.

What Is Normal?

One or two colds per year is typical, says Shelia Kingsbury, N.D., R.H. “If that increases to four to six colds—or being sick a lot in winter—it may indicate a breakdown in your immune system.” Other signs your immunity is compromised: chronic eczema, respiratory allergies and digestive issues. Digestive issues—from food intolerance to food allergy—signal poor immunity because the gut is lined with lymphatic tissue designed to protect the body from invaders. “A lot of our immune system is contained in our gut,” Kingsbury explains.