9 resistance-boosting foods and ingredients to help you win the cold war
Probiotics, or the “live active cultures” found in yogurt, are healthy bacteria that keep the gut and intestinal tract free of disease-causing germs. Although they’re available in supplement form, a study from the University of Vienna in Austria found that a daily 7-ounce dose of yogurt was just as effective in boosting immunity as popping pills.
You may not think of skin as part of your immune system. But this crucial organ, covering an impressive 16 square feet, serves as a first-line fortress against bacteria, viruses, and other undesirables. To stay strong and healthy, your skin needs vitamin A. “Vitamin A plays a major role in the production of connective tissue, a key component of skin,” explains Dr. David Katz, director of the Yale-Griffin Prevention Research Center in Derby, Conn.
Take frequent tea breaks this winter, and you may just get through it without a sniffle. Immunologists at Harvard University discovered that people who drank five cups of black tea a day for 2 weeks transformed their immune system T cells into “Hulk cells” that pumped out 10 times more cold and flu virus-fighting interferon — proteins that defend against infection — than did the immune systems of those who didn’t drink black tea. Green tea should work just as well.
When University of Nebraska researchers tested 13 brands, they found that all but one (chicken-flavored ramen noodles) blocked the migration of inflammatory white cells — an important finding, because cold symptoms are a response to the cells’ accumulation in the bronchial tubes.
The amino acid cysteine, released from chicken during cooking, chemically resembles the bronchitis drug acetylcysteine, which may explain the results. The soup’s salty broth keeps mucus thin the same way cough medicines do.
Zinc deficiency is one of the most common nutritional shortfalls among American adults, especially for vegetarians and those who’ve cut back on beef, a prime source of this immunity-bolstering mineral. And that’s unfortunate, because even mild zinc deficiency can increase your risk of infection. A 3-oz serving of lean beef (enough to make a respectable, but not decadent, roast beef sandwich) provides about 30 percent of the daily value for zinc. That’s often enough to make the difference between deficient and sufficient. Just can’t stomach beef? Try zinc-rich oysters, fortified cereals, pork, poultry, yogurt, or milk.
For centuries, people around the world have turned to mushrooms for a healthy immune system. Contemporary researchers now know why. “Studies show that mushrooms increase the production and activity of white blood cells, making them more aggressive. This is a good thing when you have an infection,” says Douglas Schar, director of the Institute of Herbal Medicine in Washington, D.C.
Fish and shellfish
Getting adequate selenium (plentiful in foods like oysters, lobsters, crabs, and clams) increased immune cell production of proteins called cytokines in a British study of 22 adults. The scientists say that cytokines help clear flu viruses out of your body.
Garlic contains the active ingredient allicin, which fights infection and bacteria. British researchers gave 146 people either a placebo or a garlic extract for 12 weeks; the garlic takers were two-thirds less likely to catch a cold.
Oats and barley
These grains contain beta-glucan, a type of fiber with antimicrobial and antioxidant capabilities more potent than echinacea, reports a Norwegian study. When animals eat this compound, they’re less likely to contract influenza, herpes, even anthrax; in humans, it boosts immunity, speeds wound healing, and may help antibiotics work better. At least one in your three daily servings of whole grains.