By Brierley Wright, M.S., R.D. , January 8, 2009 - 3:36am
’Tis the season for colds and the flu. If you’re like me, there isn’t any spare time built into the schedule to get sick.
So you can imagine how thrilled I was when, in the December issue of EatingWell Magazine, our senior nutrition advisor Rachel Johnson, Ph.D., M.P.H., R.D., revealed which 3 immune-boosting superfoods work—and what products aren’t worth the money .
• Glacéau’s Vitaminwater “Defense”: This drink, with a label that claims it is “specially formulated with nutrients required for optimal functioning of the immune system,” doesn’t deliver the mega-high doses of nutrients that Airborne does. (A 20-ounce bottle of the water contains 150 percent of the DRV of vitamin C and 25 percent for four B vitamins and zinc.) But at 125 calories per bottle, I’d rather skip it.
• Airborne: As with many label claims, Airborne’s current one begins with a kernel of truth: vitamins A, C, E, zinc and selenium—nutrients in the supplement—are among the vitamins and minerals that our immune systems need to function efficiently. According to a 2002 report in the British Journal of Nutrition, deficiencies of any of these nutrients (or of vitamins B6, B12, folic acid, copper or iron) can depress immunity.
But the key word is deficiency; most of us—save for smokers, pregnant women , breastfeeding women and the elderly—meet our needs for these nutrients with the foods we eat. (If you fall into any of those higher-risk categories, talk with your doctor before taking a supplement.) And more isn’t better. Excess amounts of many nutrients are potentially harmful, and it’s all too easy to go overboard. Just one tablet of Airborne contains 1,667 percent of the daily recommended value (DRV) for vitamin C.
• Green tea: Polyphenols, potent plant antioxidants, are what’s believed to give green tea its immune-boosting effects . One laboratory study suggested that a particular type of polyphenols called catechins may kill influenza viruses.
If you’re turned off by the bitterness of green tea—one downside of the polyphenols—proper brewing techniques can help. To maximize benefits and minimize bitterness, the Tea Council recommends using just-below-boiling water and steeping green tea no more than a minute or two. A little lemon and honey can also help blunt the bitterness. But don’t add milk, because the proteins will bind to the polyphenols, making them ineffective.
• Probiotics: These so-called “good bacteria,” found in yogurt , sauerkraut and other foods, are touted as helping prevent the GI upsets many of us succumb to during the holidays. According to a recent review in the Journal of the American Dietetic Association, regular consumption of probiotics may help your immune system work better, reduce the incidence of intestinal infections and improve digestion .
Fermented dairy products such as yogurt or kefir (a yogurt-like beverage), are good bets. Look for those labeled with a “Live & Active Cultures” seal from the National Yogurt Association, which signifies that the yogurt contains a set minimum amount of two particular types of beneficial bacteria. (While it’s not a guarantee of probiotic power—the bacterial counts don’t differentiate between added probiotic organisms and the bacteria that’s used to ferment the yogurt—the seal is a helpful start.)
With the new “probiotic” cereals and granola bars, it’s not always clear how much good bacteria the manufacturers actually add to the products or whether the strains included are effective. If you really want to know about the science backing a product’s “probiotic power,” contact the manufacturer.
• A multivitamin: If you’re not eating as well as you should, consider taking a multivitamin/mineral supplement—one with no more than 100 percent of the DRV—as extra insurance.