How to Fight Colds, Flus, and Infections at Any Age(How to Fight Colds, Flus, and Infections at Any Age)

No matter where you go in life, somebody's sneezing, and possibly spreading colds, the flu, or other infections. Strangers on the elevator, kids at day care, even those self-important colleagues who refuse to take sick days— -- they all pose a risk. Avoiding germy people is your best defense, but boosting your immunity is just as important for preventing colds, flus, and infections. And because your immune system naturally weakens as you age, charging it up is crucial during cold-and-flu season. Here, an age-specific plan for optimum protection.

Your 30s

Limit sugar and alcohol. Life in your 30s often means fast-tracking a career, starting a family, and keeping up with an active social life -- —all at the same time. That can mean meals on the fly, sugary snacks for energy, and some social drinking on the weekends. As a result, your immunity can suffer, says Mark Moyad, MD, director of preventive and alternative medicine at the University of Michigan Medical Center. "The sugar in just one can of soda can compromise immune system function by 30% for up to three hours," he explains. How? By immobilizing some immunity cells and hurting their ability to surround and ultimately destroy bacteria. In addition, anything more than a few alcoholic drinks per week reduces the number of immunity-providing cells your body produces.

Dr. Moyad recommends that you not only limit drinking but also replace sweets with high-fiber snacks like oatmeal, whole-wheat muffins, or apples. Fiber is actually a prebiotic—a food source for probiotics, the friendly bacteria in yogurt and other products that help keep your gut strong enough to fend off invading bacteria and viruses. Also, try starting your day with cereals containing buckwheat (try Arrowhead Mills Organic Maple Buckwheat Flakes) or wheat germ (Kretschmer Wheat Germ); both are high in polyphenols, natural compounds linked to longer life and increased immunity.

Work out smarter, not harder. Robo-routines that get you a hard body in a few weeks may boost your physical confidence, but they actually slow down your immune system, says Len Horovitz, MD, a pulmonary specialist and flu expert at Lenox Hill Hospital in New York City. Studies show that moderate exercise, however, helps immune cells circulate through the bloodstream at a more rapid pace, making it less likely that bacteria or viruses will slip through unnoticed. And the effect is cumulative over time. Aim for about 20 minutes of aerobic exercise (walking or running, for instance) plus 15 to 20 minutes of strength training three times a week. Then try some yoga for an extra boost: A Washington State University study suggests that doing yoga three times weekly -- —the equivalent of a moderate-intensity exercise program— -- reduces a key marker for stress inside the body, helping to increase immunity.

Your 40s

Go to bed earlier. You may relish your downtime before bed— -- who doesn't want an hour to read or watch TV after the evening rigors of helping with homework, doing the dishes or laundry, and whipping the household budget into shape? But if you relax at the expense of getting real sleep, fighting off colds gets harder. As little as 30 to 60 minutes of additional sack time per night is enough to up your immunity, Dr. Moyad says. "Sleep is a restorative process, and it's necessary for the immune system to function properly," he explains. Even a nap can help. "When you feel tired don't fight it," Dr. Moyad adds. "It's your body's way of telling you that you need to recharge."

Learn new ways to relax. Chronic stress— -- whether it's from a frustrating daily commute or problems on the job -- —slows down your immune system, making it react less efficiently to a threat like the flu virus, for instance. To fight back, try new forms of heavy-duty relaxation, says Jacob Teitelbaum, MD, medical director of the nationwide Fibromyalgia and Fatigue Centers; he recommends transcendental meditation.

Your 50s and beyond

Amp up antioxidants. In your 50s, your risk of disease rises fast. To pump up your immunity, add more antioxidant-rich fruits and veggies to your diet. Research from the University of California, Berkeley, suggests that broccoli, cabbage, and kale offer the biggest immune system boost because they contain an important cancer-fighting compound. You hated kale the last time you tried it 10 years ago? Some evidence suggests that taste buds can "mature" in a way that can turn foods you've never liked into pleasurable adventures.

Another smart choice, according to pharmacist Suzy Cohen, RPh, author of Drug Muggers: How to Keep Your Medicine From Stealing the Life Out of You, is a cup of tea -- —but not just any cup. Her favorite is matcha, a powdered form of ground-up green tea leaves sold under many brand names and found in most health-food stores as well as online. One cup of matcha will net you the antioxidant protection found in 10 cups of brewed green tea and up to 100 times the antioxidant power of vitamins C and, she says. Dr. Moyad suggests adding a spoonful of honey to your tea for extra protection: "It has incredible antibacterial powers."

Follow your dreams. Pay a little more attention to those long-lost goals that help define the meaning of life— -- and your immune system's natural killer cells may multiply, according to a University of California, Los Angeles, study. While researchers aren't sure why, one theory suggests that focusing on what you really want to do reduces the immunity-robbing impact of everyday stress. Dr. Moyad says volunteering in your community can pump up your germ-fighting powers even more. Studies show that those who volunteer not only are healthier but actually live longer than folks who don't. Stress reduction may be the hidden link.

Get your groove back. Now that the kids may be out of the house for long periods, make more time for sex. A study from Wilkes University in Wilkes-Barre, Pa., found that men and women who had one to two sexual encounters per week had a 30% increase in IgA, antibodies found in saliva and mucous membranes that are considered the first line of defense against cold and flu viruses. Exactly how or why sex causes the increase is not well understood— -- but sometimes science is just there to enjoy!