Your body is capable of many amazing things, but perhaps none is as extraordinary as its ability to protect you from infection. Millions of cells, each with a highly specialized function, communicate and collaborate with each other not only to destroy pathogens but also to remember them should they try to invade again.
All this goes on without your even realizing it—well, except for the occasional microbe that slips through undetected. Given the sheer volume of germs that you encounter on a daily basis, your immune system’s track record is quite impressive. But it needs proper care and feeding to keep on doing what it does so well.
That’s where you come in. By taking steps to strengthen your immune function and reduce your germ exposure, you can greatly improve your odds of not getting sick. We’re not asking you to reinvent your lifestyle for the sake of staying healthy, because you really don’t need to. As you’ll see in this chapter, sometimes the simplest changes can yield the most dramatic results.
With guidance from our team of health experts, we’ve put together the following list of best practices to keep your immune system primed for action and knock germs off their game. These tips are effective, easy to use, and even a bit unexpected. You needn’t try all of them, of course—though the more you make part of your life, the better your chances of staying disease-free!
That’s a Fact 
Your vacuum cleaner may not be as clean as you think. Because they suck up bacteria and food particles, vacuums can spread germs around your house. In a study at the University of Arizona, 13 percent of all vacuum cleaner brushes tested positive for Escherichia coli. To keep your vacuum cleaner clean, change the bag frequently—or, if you have a bagless model, clean the canister with bleach regularly.
Eat Well, Stay Well
Just as your car needs gas and oil to run properly, your body depends on key nutrients to fuel its most basic processes, including your immune function. Your best strategy is to strive for the diversity of nutrients that comes only from a healthy, balanced diet, advises Ann G. Kulze, MD, founder and CEO of Just Wellness LLC and author of Dr. Ann’s 10-Step Diet. Then, if you need to, add nutritional supplements to make up for any shortfall.
1 Eat for good health, not just immunity
Why it works A healthy diet nourishes your entire body, not just certain parts, explains David L. Katz, MD, MPH, director of the Yale Griffin Prevention Research Center in Derby, Connecticut, and author of The Way to Eat. “You need white blood cells for good immunity, and they require good bone marrow to form and a healthy heart and blood vessels to travel throughout your body,” he says. “All of your body’s systems are interrelated. That’s why robust immunity equals robust health—and why healthy eating is really a holistic thing.”
Where to start Your body will thrive on a diet that features whole grains, fruits and vegetables, and lean proteins such as chicken and fish. Nuts, seeds, olive oil, and avocados are good choices for monounsaturated fats. And don’t forget fatty fish like salmon and mackerel for a healthy dose of omega-3 fatty acids.
What your body doesn’t need are refined grains, sugars, and the saturated fats in red meats and full-fat dairy products. Try to limit these as much as possible.
For extra credit Here’s a super-easy strategy to make sure that you’re getting the proper mix of foods and nutrients at every meal. Imagine that your dinner plate is divided into quarters. Two of those quarters, or one-half of your plate, should be occupied by veggies and fruits. Then one-quarter is for whole grains, and the remaining one-quarter is for lean protein.
2 Pick brightly colored produce
Why it works Pretty much any fruit or veggie has something to offer your immune system. But for immune-boosting prowess, Dr. Kulze says, these are the cream of the crop: berries, whole citrus fruits, kiwi, apples, red grapes, kale, onions, spinach, sweet potatoes, and carrots. What do they have in common? Their eye-catching colors, which tell you at a glance that they’re loaded with phytochemicals.
“The interesting thing about phytochemicals is that when they’re isolated in supplement form, they seem to lose their immune-boosting benefits,” Dr. Kulze notes. “That’s why eating fruits and vegetables is the best strategy for getting the hundreds of micronutrients that work synergistically to enhance your immunity.”
Where to start Choose fresh fruits and veggies when in season, frozen at other times of year. How you eat them is up to you! For example, you might sprinkle berries on your morning cereal, toss spinach and kale into a salad, or nibble on baby carrots for an afternoon snack. The possibilities are endless!
For extra credit Pair your produce with other healthy foods for a more powerful immune punch. You might mix your berries into yogurt containing active cultures, the beneficial bacteria that help keep the bad bugs in check. Or serve up a sweet potato as a side dish to wild salmon, which is rich in omega-3 fatty acids.
3 Be unconventional—go organic!
Why it works To most of us, a vegetable is a vegetable and a fruit a fruit. But some of our experts, including Neal Barnard, MD, president of the Physicians Committee for Responsible Medicine in Washington, D.C., believe that organic is the only choice if your goal is to ensure the robust function of your immune system.
One reason is that organic produce is more nutritious, with improved vitamin and mineral content, according to studies. Two, it contains fewer pesticides, among other chemicals.
Now the jury is out on just how harmful pesticides are. But in Dr. Barnard’s opinion, “It’s likely choosing organic products will result in lower cancer rates and, for women who are pregnant, fewer birth defects.”
Where to start If you’re still on the fence about organics, you needn’t be a complete convert. Instead, try making the switch for just those fruits and veggies with the greatest pesticide content. As a general rule, peaches, apples, and bell peppers rank high for contaminants, while onions, avocados, and frozen sweet corn are largely contaminant-free. For a list of foods and their pesticide scores, visit www.foodnews.org.
For extra credit Before buying organic produce at the supermarket, check out what’s available at your local farmer’s market. “I am quite certain that I can find organic produce grown under large-scale farming conditions that is potentially less nutritious than produce grown locally,” says Christopher Gardner, PhD, an associate professor in the Prevention Research Center at Stanford University School of Medicine.
4 Make omega-3s your favorite fat
Why it works Omega-3s help reduce inflammation, which is a factor in colds and flu, among many other conditions. If the latest research is any indication, that may be just one aspect of how these beneficial fats contribute to immunity. “Omega-3s are almost like the CEOs at the cellular level,” Dr. Kulze says. “They create building blocks within the cells that drive the body’s immune response.”
Where to start Currently, there is no official guideline for omega-3 intake. To get the most from these beneficial fats, the American Heart Association recommends eating a serving of fish—particularly fatty fish like mackerel, lake trout, herring, sardines, albacore tuna, and salmon—at least twice a week.
For extra credit Although food should be your primary source of any nutrient, including omega-3s, Dr. Katz says this is one instance where supplementing may make good sense. “The typical American diet contains too many omega-6 fatty acids and not enough omega-3s,” he notes. “A supplement can help restore proper balance.”
Dr. Kulze likes a product called Nordic Naturals Omega-3D, which combines fish oil with another immune booster, vitamin D. To learn more about this product, visit www.nordicnaturals.com.
5 Use garlic liberally
Why it works Vampires aren’t the only ones to be repelled by garlic. Bacteria and viruses are averse to its properties, too. The pungent bulb is an established germ fighter, and it enhances immunity besides.
Garlic owes its therapeutic properties to allicin, the chemical compound that’s responsible for its very distinctive smell. Allicin increases both natural killer cells and T-lymphocytes, the white blood cells that seek out and destroy invading pathogens. “It’s believed that people who ate a lot of raw garlic were the ones who survived the plague,” says Susan Schenck, co-author of The Live Food Factor.
Where to start To get the most benefit from garlic, use the fresh stuff. “Fresh garlic that you mince yourself is a lot more potent than the dried or processed kind that you find at the supermarket,” Dr. Kulze says. She recommends cutting it up about 10 to 15 minutes before you plan to use it.
For extra credit Eating raw garlic isn’t for the faint-hearted; many people find the smell and taste overpowering. But cooking garlic can reduce its antimicrobial effects. If possible, try not to add it until the very end of the cooking process to help preserve its allicin content. Then stir it into soups and sauces, sprinkle it over fajitas and stir-fries, and use it as a garnish on steaks and burgers. Just remember, a little garlic goes a long way!
6 Add a little spice to your meals
Why it works The native cuisines of warmer, subtropical climates tend to feature a lot of spicy dishes, and for good reason. “The spices added to the food help keep it from spoiling, which prevents a lot of food-borne illness,” Dr. Katz explains.
Many of these aromatic spices have potent antiviral properties. They’re also excellent natural immune boosters, says nutritional consultant Steven Kushner, PhD. Because they work with your body’s own immunity, they’re less likely to cause the side effects that can accompany antiviral drugs.
Even the heat generated by certain spices has benefits. It clears mucus out of your nose and mouth while helping cilia work more efficiently, Dr. Kulze says. (Cilia are microscopic hairlike structures that line the respiratory tract and keep microbes from reaching your lungs.)
Where to start You can find hot and spicy dishes in many of the world’s cuisines, especially Indian, Asian, and Mexican. Or simply experiment with various spices to find out how they might enhance the flavors of your favorite fare.
For extra credit Certain spices, such as cinnamon, cayenne, turmeric, and ginger, have been studied specifically for their antiviral properties, Dr. Kushner says. So find creative ways to incorporate these spices into your meals. Cinnamon gives a little kick even to plain old toast and applesauce, while cayenne is bold enough for barbecue and chili. Both turmeric and ginger are staples of Indian cooking—though for the less adventurous, a cup of ginger tea will do quite nicely.
7 Pay attention to vitamin D
Why it works Though much of the research on vitamin D is fairly new, all indications point to the nutrient being more important to our overall health than was previously realized. Among its growing list of benefits is its role in regulating immune function. An estimated 60 percent of Americans aren’t getting enough vitamin D, and this may help explain why so many of us end up sick.
Where to start No doubt one of the reasons for our nationwide vitamin D shortage is its relative scarcity in our food supply. Fortified milk and breakfast cereals deliver the most generous amounts, as do fatty fish such as salmon, mackerel, and canned sardines and tuna.
The best natural source of vitamin D is the sun’s ultraviolet rays, which your body converts to the nutrient. For this to work, though, you need to be out in the sun without sunscreen—and that’s the rub for some experts, who are debating whether the benefits of brief sun exposure outweigh the risks.
For now, we recommend 10 to 15 minutes of unprotected sun exposure daily. If you’re going to stay outdoors for longer than that, definitely slather on the sunscreen. Wear a hat and sunglasses, too.
For extra credit As for the omega-3s, you might want to consider taking vitamin D in supplement form, especially if you live in an area that doesn’t get much sun. Many multivitamins provide the Daily Value (DV) of vitamin D, which is 400 IU.
8 Check your zinc intake
Why it works Zinc stimulates lymphocytes, a type of white blood cell that is critical to your body’s natural defenses. It’s one of the few nutrients that appears to play a direct role in shortening the duration of a cold.
Where to start For general immune enhancement, simply increase your intake of zinc-rich foods. Just six oysters provide five times the DV of the mineral, which is 15 milligrams. Other good food sources include lean protein (turkey and chicken), beans, and fortified cereals.
For extra credit If you think you may be coming down with a cold, start taking zinc at the first sign of symptoms. Studies suggest that zinc gluconate lozenges, such as Cold-Eeze, deliver more zinc into your body than other formulations, such as zinc citrate and thus are more effective.
9 Make the most of mushrooms
Why it works For more than 2,000 years, practitioners of traditional Chinese medicine have prescribed mushrooms to strengthen immune function. Now modern research is confirming the therapeutic properties of these versatile fungi.
For one recent study, conducted jointly by researchers at Pennsylvania State University and Arizona State University, five different kinds of mushrooms were incorporated into the diets of laboratory mice. When these animals were given a chemical that normally triggers colon inflammation and the growth of colon tumors, they showed no signs of adverse health effects. The reason: The mushrooms appeared to stimulate production of macrophages and T lymphocytes, two key cellular components of the human immune response.
Where to start These days, many supermarkets carry the various kinds of mushrooms traditionally used for medicinal purposes, including maitake, reishi, and shiitake. Interestingly, in the laboratory study mentioned above, the uncele-brated white button mushroom—the kind commonly used to top pizzas and salads—appeared to enhance immunity even better than the maitake or shiitake varieties.
For extra credit Fred Pescatore, MD, a traditionally trained physician who practices nutritional medicine and author of The Hamptons Diet, recommends a supplement called AHCC (short for active hexose correlated compounds). It’s a blend of medicinal mushroom compounds that appears to have immune-boosting effects, according to studies conducted at Columbia, Harvard, Yale, and other institutions. Several formulations are available, but Dr. Pescatore prefers Mush Rex from Madre Labs and Kinoko Gold AHCC from Quality of Life Labs.
10 Give ginseng a try
Why it works Among herbalists, ginseng is what’s known as an adaptogen, which means that it has broad-spectrum health effects. One species, North American ginseng, may be of particular benefit to the immune system. In a 2005 study involving 323 adults who had developed two or more colds in the previous year, taking North American ginseng supplement for 4 months reduced the number of colds, the severity of symptoms, and the number of days with symptoms.
The herb appears to get its immune-friendly effects from compounds known as polysaccharides. “These compounds stimulate macrophages and natural killer cells to release antimicrobial agents called cytokines,” says Sherry Torkos, a pharmacist in Fort Erie, Ontario, and author of The Canadian Encyclopedia of Natural Medicine. “The cytokines directly attack viruses and bacteria and also activate immune cells that help protect the body against future attacks.”
Where to start Ginseng is a popular ingredient in energy drinks, but these often contain large amounts of caffeine, not to mention other questionable substances. You’re better off looking for a tea bag blend made with ginseng. Make the tea according to package instructions. Another option is to take 200 milligrams of a North American ginseng extract once or twice daily.
For extra credit A product called Cold-Fx has American ginseng as its active ingredient. It’s available online and in many pharmacies.
Does it work?
Echinacea
Don’t bother
For a 2005 study published in the New England Journal of Medicine, researchers gave 400 healthy volunteers either a placebo or one of three different doses of echinacea. After seven days of treatment, the volunteers were exposed to cold viruses via a nasal spray. Compared to the group given the placebo, the same number of people taking echinacea came down with colds. The dose didn’t make a difference.
Echinacea is not without side effects, says Margaret Lewin, MD, clinical assistant professor of medicine at Cornell University and chief medical director of Cinergy Health. “It can cause drug interactions, allergic reactions, fertility problems, and abdominal pain and diarrhea,” she says.
11 Tap the power of probiotics
Why it works There might be something innately unappealing about intentionally consuming a food that contains (gulp!) live bacteria cultures. But these organisms are the good guys. They take up temporary residence in your gut, where they’re able to counter the nasty effects of pathogens—the microbes that cause disease.
In a study of the probiotic Lactobacillus reuteri, only 11 percent of people given the probiotic took sick leave from work over the course of 80 days, compared to 26 percent of those given a placebo. The results were even more dramatic among people on night shift: No one in the probiotic group took sick leave, compared to 33 percent of the placebo group.
Where to start Dr. Kulze is a big fan of eating yogurt with live active cultures every day. It’s an easy way to give your body the benefit of probiotics—and it’s a source of protein and calcium that even people with lactose intolerance can stomach. “I recommend getting plain low-fat yogurt and mixing in your own fruit,” Dr. Kulze says. “There’s usually a lot of added sugar in the fruit varieties of yogurt.” Look for the phrase “live active cultures” on the label.
For extra credit Scientific understanding of probiotics is becoming increasingly more sophisticated; doctors are now able to identify specific probiotics that are helpful for specific ailments. “Probiotics clearly have a benefit,” Dr. Katz says. “This is a good example of when you should talk with your doctor—to find out what probiotic regimen might be right for you.”
12 Stay hydrated
Why it works Like the rest of your body, your immune system depends on water to do its thing. “When you’re dehydrated, your immunity is compromised,” Dr. Kulze says. “Your cilia don’t function properly, your mucus doesn’t do what it’s supposed to, even your blood doesn’t flow as well.”
Where to start Let your body tell you how much water it needs. “The eight to ten 8-ounce glasses a day rule has been disproven,” Dr. Katz says. “The more important guideline is to drink when you’re thirsty. People who eat well tend to get plenty of fluids from fruits and vegetables, so they may not need as much water throughout the day.”
Another good indicator of hydration is the color and frequency of your urine. “If you’re getting enough fluids, you should urinate every 2 to 3 hours,and your urine should be alight straw color,” Dr. Katz says.
For extra credit Don’t forget to gargle! In a Japanese study involving 387 healthy volunteers, those who gargled plain water for 15 seconds three times a day reduced their chances of developing an upper respiratory infection by 36 percent compared to those who didn’t gargle.
13 Drink two cups of tea daily
Why it works Tea is brimming with phytochemicals that seem to be the mechanism by which tea fends off illness. A recent study by Jack F. Bukowski, MD, PhD, looked specifically at ethylamine, a compound produced when the tea ingredient L-theanine is broken down in the liver. Dr. Bukowski found that when certain T cells were exposed to ethylamine, they multiplied 10-fold and were better able to fight off bacteria. Other research indicates that tea might play a role in battling viruses and parasites.
Where to start All tea seems to have immune-boosting properties, but research indicates that green tea trumps black—and white tea may be best of all. “Past studies have shown that green tea stimulates the immune system,” says Milton Schiffenbauer, PhD, a microbiologist and professor in the department of biology of Pace University Dyson College of Arts and Sciences. “Our research shows that white tea extract can actually destroy the organisms that cause disease.” Whichever variety you choose, Dr. Kulze recommends drinking at least two cups of freshly brewed tea a day.
For extra credit Drop a thumbnail-size chunk of ginger root into your tea—skin and all—and let it steep for an additional 3 to 5 minutes. Sip the tea with the ginger still in it, then chew on the ginger afterward. “Ginger goes great with tea and contributes even more anti-inflammatory and antiviral compounds,” Dr. Kulze says.
14 Practice safe food preparation
Why it works Though it makes headlines when our food supply is tainted in a factory or a restaurant, the reality is that most foodborne illness is caused by mistakes at home. Food gets left out too long; vegetables are contaminated by meat cut on the same surface; milk lingers in the fridge 10 days past its expiration date. Before you know it, you’re hosting a breeding ground for bacteria and other nasty microbes.
Where to start The U.S. Department of Agriculture’s Fight BAC! program distills the principles of safe food handling to four easy-to-remember guidelines: clean, separate, cook, and chill.
Clean your hands as well as any surfaces on which you’ll be working before you begin preparing food.
Separate foods—especially raw meats—in the grocery cart, in the refrigerator, and when you’re preparing a meal. This helps prevent cross-contamination.
Cook foods at the proper temperature and to proper doneness. You can use a food thermometer to check the internal temperature.
Chill foods at 40°F or below to prevent spoilage. Throw out any food that has sat out for more than 2 hours (or 1 hour when the air temperature is above 90°F).
For extra credit Visit www.befoodsafe.gov for more information about safe food handling, including proper cooking and chilling instructions for specific foods.
Move for Maximum Immunity
For weight loss and overall health, regular exercise tends to follow good nutrition on almost every expert’s list. That’s why in 2005, the USDA and the Department of Health and Human Services released their updated guidelines for physical activity. Thirty minutes a day used to be the standard, but now it’s the bare minimum. Sixty to 90 minutes is the new goal.
Just as feeding your body properly gives it the necessary fuel to fend off infection, moving your body regularly helps keep it resilient. “Exercise is a crucial component of immune function,” affirms Erika Schwartz, MD, chief medical officer of www.healthandprevention.com. “During exercise, you release hormones called endorphins that stimulate your immune system. You also activate specific white blood cells that fight infection.”
15 Exercise for 30 to 90 minutes every day
Why it works Moving your body affects your immune system directly and indirectly. For example, when you’re under stress, your body releases stress hormones such as adrenaline, noradrenaline, and cortisol. They serve an important purpose, in terms of helping you to deal with stressors. But if they circulate in your system for too long, they can do more harm than good. When you exercise, you burn off stress hormones—which, in combination with those endorphins mentioned earlier, helps restore balance.
Where to start Any physical activity is good to start, especially if you’ve been relatively sedentary. Walking is a popular choice because it can be done virtually anytime and anywhere. Simple stretching, short bouts of bicycling, and yoga are other gentle activities to help ease you into a fitness routine.
For extra credit Although you definitely want to start slow, kicking up the intensity of your workouts is key to reaping their full benefit. “During exercise, your body temperature rises slightly, and this increase helps kill off bacteria and viruses,” Dr. Schwartz explains. “Thirty minutes of aerobic or cardiovascular activity will achieve these effects. Slow walking and stretching will not.”
16 Be careful not to overdo
Why it works Just as with red wine and dark chocolate, you can get too much of a good thing with exercise. “Research shows that more than 90 minutes of high-intensity endurance exercise can make people more susceptible to illness for several hours afterward,” says Jenny Evans, a stress and fitness physiologist and founder of Power-House Performance Coaching.
This happens, at least in part, because of hormones. “Intense physical activity can trigger the release of stress hormones, which reduce long-term immunity,” Evans explains. But excessive exercise has a much more basic impact on the body as well. “It can deplete glycogen and water and prevent the body from having the required energy for proper immune function,” says Shane Ellison, MS, an organic chemist and author of Over-the-Counter Natural Cures.
Where to start Keep your workouts within the recommended 30- to 90-minute time frame. “Too much intense exercise can compromise immunity, but the average exerciser who does no more than 90 minutes per day has nothing to worry about,” Evans says.
For extra credit If you do happen to fall ill after overexertion, the solution is easy enough: “Take time off to let your body repair and recharge itself,” says Lou Schuler, a certified strength and conditioning specialist and author of six books, including The New Rules of Lifting. “Sometimes a cold or a bout of flu is a blessing in disguise, since it forces you to take a break from your workouts.”
17 Do it for you
Why it works Exercise that improves your body shape also improves your self-esteem—and that’s a good thing for your immune system. “The better you feel about how you look, the more confident you become, and the less stress you feel in various social circumstances,” says Dr. Schwartz. “This leads directly to improved immune function, because stress lowers immune response.”
Reality Check 
The 5-second rule: When you drop a piece of food on the floor, if you pick it up within 5 seconds, it will still be germ-free.
Actually, 5 seconds is a bit on the conservative side, according to student researchers at Connecticut College in New London, who found that bacteria need more than 5 seconds to contaminate dropped food. For their study, the students left pieces of wet food (apple slices) and dry food (Skittles) on the floor for various periods of time, then analyzed the samples for contamination. It took 30 seconds for bacteria to find their way onto the apples; as for the Skittles, nearly 5 minutes elapsed before they were attacked.
Where to start The most effective workout for slimming down and shaping up combines aerobic activity with strength training. “Aerobic activity stimulates the release of endorphins, which increase your sense of well-being. But it’s really strength training that builds muscle mass and improves your appearance,” Dr. Schwartz says.
If you’re new to strength training, it’s a good idea to schedule at least a few sessions with a personal trainer, who can show you proper technique and tailor a workout to your skill level. And don’t worry about becoming too muscular; you can get tone and definition without bodybuilder bulk.
For extra credit Focus on your core—thatis, the muscle groups of your belly and your mid- and lower back. “Core strength training directly changes posture and thus enhances self-confidence,” Dr. Schwartz says. She recommends abdominal exercises and Pilates classes to target your core muscles.
18 Sign up for a yoga class
Why it works “With yoga, it is not so much the activity itself but the destressing that goes along with it,” says Walter Gaman, MD, managing partner of Executive Medicine of Texas and co-author of Stay Young: Beating the Odds in a Busy World. “Yoga is better for the body and mind because it incorporates both, unlike running on a treadmill, which works just the body.”
In a small study at Washington State University, 19 breast cancer patients who took 8 weeks of Iyengar yoga classes showed reduced activation of NF-kB, a protein that the body commonly activates when it’s under stress.
Where to start Taking a yoga class from a certified instructor is the best way to get proper instruction in the movements and poses. If you don’t have the time or finances to enroll in a class, the next best thing is a beginner’s yoga DVD.
For extra credit To get a little variety and extra benefit, you can try different styles of yoga. The latest trend is something called Hot Yoga, in which you practice in a room heated to 95° to 100°F. “Hot Yoga can be challenging physically and thermally—a perfect combination for boosting immunity!” Ellison says.
19 Take your workout outside
Why it works Being outdoors can lift your mood, and a positive mood enhances the immune-boosting effects of exercise. “Exercising outdoors is fantastic,” says Beth Shaw, a licensed yoga instructor and founder and president of Yoga Fit Training Systems. “If the air is fresh and clean, I will take an outdoor activity over an indoor activity any day of the week.”
Dr. Gaman points out that when you’re outdoors, you breathe in more fresh oxygen, which is fuel for your immune cells. And if the sun happens to be shining, those ultraviolet rays help your body manufacture another important immune booster, vitamin D.
Where to start It really doesn’t matter what you do, though typically indoor activities like yoga and tai chi can be more effective when you take them outside. “Their healing benefits are magnified when they’re performed by a body of water or in another natural setting,” says Joseph Andreula, an owner of 18 gyms in New York and New Jersey and a member of the International Fitness Standards Advisory Council.
For extra credit Regardless of where you intend to exercise, check the air quality first. “Any form of activity will stress your immune system if pollution is high or ventilation is poor,” Andreula says. “Ideally, you can exercise outdoors if the air is fresh and the climate is suitable, or indoors if the space is well ventilated.”
20 Do what you love
Why it works Sticking with an exercise program is much easier when it involves an activity that you enjoy. “Any activity done regularly beats one that isn’t done at all,” Andreula says.
Where to start Think back to what got you moving as a kid. Was it riding a bike? Swimming? Dancing? Whatever it was, maybe you can pick up where you left off. Or perhaps there’s an activity that you’ve been curious about. Now is as good a time as any to try it!
For extra credit Recruit a workout buddy or two. On those days when you’re not feeling up to exercise, knowing that someone is counting on you can be motivation enough to keep your commitment. It’s also an opportunity to strengthen social ties, a perk of exercise that gets little recognition for its immune-enhancing benefits.
21 Prep for exertion with vitamin C
Why it works Vitamin C has taken a bit of a beating since research revealed that it doesn’t live up to its reputation as a potent cold and flu fighter. As often is the case, though, this “rule” has one exception: those who engage in strenuous activity. Across six studies involving 642 participants—including marathoners, skiers, and soldiers working in subarctic conditions—vitamin C supplements successfully reduced the chances of a cold by 50 percent.
Why this is true isn’t quite clear, but Mark A. Moyad, MD, MPH, director of preventive and alternative medicine at the University of Michigan in Ann Arbor, has a theory. “When your body endures the oxidative stress that comes from a strenuous activity like running a marathon, it generates a ton of free radicals,” he says. “So it makes sense that introducing a powerful antioxidant like vitamin C into the body would help to absorb some of that free radical damage and reduce its effects.”
Where to start As mentioned earlier, your immune system can take a beating from long bouts of high-intensity exercise. So if you’re expecting to engage in a strenuous activity—such as a charity 10K, or even a physically demanding job—you might want reinforce your natural defenses with a daily 400-milligram dose of vitamin C.
For extra credit Stick with the recommended dosage. While a little vitamin C may be good for your immune system, more isn’t necessarily better. “Studies have shown that your body can’t absorb more than 400 milligrams at a time,” Dr. Kulze says.
22 Slim down if you need to
Why it works “Of all of the causes of depressed immunity, obesity is at the top of my list,” Dr. Moyad says. “That’s why I try not to discourage any form of activity. As long as people are doing something, they are taking steps toward getting healthier.”
It goes back to Dr. Katz’s idea of how one aspect of our health can influence all the others. People who weigh more than they should are more likely to be sedentary, to eat poorly, and to feel stressed—each of which contributes to depressed immunity. Studies confirm that reduced immune function is more common among those who are overweight or obese than among those who aren’t.
Where to start To lose weight, you need to use more calories than you consume. So get moving, even if it’s just a walk around the block at first. You have to start somewhere! What’s important now is to focus on what you can do, not on what you can’t, Dr. Moyad says. You’ll be surprised by how quickly you see results, including on the scale.
For extra credit As your fitness level increases, continue to challenge yourself—whether by picking up your pace when you walk, or switching to heavier weights when you lift. You’ll burn fat and build muscle, which together advance you toward your weight-loss goal—and give you a good immune boost besides.
Say Goodnight to Germs
Sleep just might be the Rodney Dangerfield of immune function: It gets no respect, at least as far as its contribution to restoring and sharpening our natural defenses. “Most people know what they must do as far as proper nutrition and exercise,” says Carol Ash, DO, medical director of the Sleep for Life Center in Hillsborough, New Jersey. “They aren’t so familiar with the basics of healthy sleep.”
We need to take our sleep more seriously, because it’s vital downtime that allows our bodies’ various systems—including the immune system—to reboot. Even researchers have been surprised by just how big of an impact sleep has on immunity. “Our most important generator of energy is sleep,” notes Barry Krakow, MD, a sleep specialist and author of Sound Sleep, Sound Mind: 7 Keys to Sleeping through the Night.“ Sleep helps you to cope with stress, be productive, and avoid infection.”
23 Make sure you get enough
Why it works In a nutshell, a certain amount of sleep is necessary to recharge your batteries each night. “Studies have demonstrated that getting less than an optimum amount impairs the function of immune cells that are important for fighting infection,” Dr. Ash says.
That’s a Fact 
Freshly laundered clothes and linens may still harbor microbes. Disease-causing bacteria and viruses can linger even after clothes and linens have been washed and dried. To kill what’s lurking in your laundry, wash underwear, bath towels, and kitchen linens separately, using hot water and chlorine bleach or a detergent that contains sanitizer.
The findings of a recent study involving 153 healthy men and women show how dramatic the effects of sleep can be, especially when it comes to fending off the common cold. After observing their volunteers’ sleep habits for 2 weeks, researchers concluded that people who slept less than 7 hours a night were almost three times as likely to catch a cold as those who slept 8 hours or more.
Where to start As far as how much sleep you need, that’s coded in your DNA, Dr. Ash says. While there is no universal number of hours that works for everyone, 7 to 9 is the usual range.{41}
“We do know that getting less than 7 hours is problematic for many of us,” Dr. Ash adds. “A poll by the National Sleep Foundation found that 2 in 10 Americans get less than 6 hours of sleep a night”—a statistic that concerns most sleep specialists.
For extra credit You can prime your body and mind for a good night’s sleep by allowing yourself an hour before bedtime to relax and reflect. Use this time to practice a few simple stretches or to meditate, which can help you unwind. You might want to consider investing in a white noise machine, which can help block out any background noise that can keep you from nodding off. These devices are widely available in retail stores and online.
24 Focus on quality, not quantity
Why it works Though many studies report on the number of hours of sleep because it’s easy to track, Dr. Krakow agrees that the real issue is not how much you snooze but how well. When you don’t get good-quality sleep, you’re opening your body to all kinds of problems, including reduced immunity. “While you’re sleeping, your body is oxygenating your blood and preparing you for another day,” Dr. Krakow says. “When you don’t sleep well, this oxygenation fluctuates, and your body hates that.”
Where to start If you suspect that you might be a poor sleeper, ask yourself (or your bedmate) whether you snore, toss and turn, or wake up frequently—all classic signs of a bad night’s sleep. Also pay attention to how you feel the next day. “You need to get a good assessment of your energy level,” Dr. Krakow says. “Most people are so tired all the time that they don’t even realize it. But if you step back and truly think about what your energy level is, you can get a sense of how tired you really are.”
For extra credit It’s not uncommon to have a restless or sleepless night on occasion. But if poor-quality sleep persists, schedule an appointment with your doctor or a sleep specialist. He or she can help pinpoint the problem and recommend a treatment plan to get you the truly good night’s sleep that your body needs.
25 Clear up nasal congestion
Why it works The rattling and gurgling that’s characteristic of clogged nasal passages can weaken immunity, and not just by disrupting sleep. “If you breathe poorly while you sleep, it wreaks havoc on your airways, causing irritation and inflammation in your nose and throat,” Dr. Krakow says. “This leaves you more susceptible to colds and flu.”
Where to start If you find yourself sneezing and sniffling during the day from allergies or other nasal irritants, taking care of this nose nuisance is a critical step toward sleeping soundly at night. Your doctor can recommend an appropriate regimen of allergy medication, nasal spray, and whatever else is necessary to ease your nighttime breathing. “You need to develop a zero-tolerance policy toward nasal congestion,” Dr. Krakow says.
For extra credit Try Breathe Right nasal strips. “A lot of my patients have greatly improved their sleep just by wearing these strips at night,” Dr. Krakow says.
26 Create an ideal sleep setting
Why it works Anything in your bedroom that doesn’t directly pertain to sleep is a potential distraction. It can cause your mind to wander from the task at hand, which is to settle in for a long night of solid shut-eye. “Remove all possible stressors from the room that you sleep in,” Dr. Schwartz advises. “Work stuff should never make it to the bedroom.”
Where to start Start by clearing your bedroom of televisions, computers, and any other electronics. Reserve this space for sleep and sex—nothing else.
For extra credit Assess your bedroom decor; is it conducive to sound sleep? Dr. Ash recommends decorating with calming, soothing colors and comforting materials—including your mattress and pillows. Also, adjust your bedroom thermostat to a cool but comfortable temperature, anywhere from 54° to 74°F. The ideal temperature varies from one person to the next, but generally, a cool room helps to maintain sleep.
27 Make your room as dark as possible
Why it works The easy answer is that in a dark room, you’re more likely to fall asleep and stay asleep. But Torkos says that the physiology is a little more complex than that. “In response to darkness, your body secretes a hormone called melatonin, which regulates your sleep cycle,” Torkos explains. “Melatonin also supports immune function by acting as an antioxidant and by increasing the activity of T cells and the production of immune-stimulating interleukins and cytokines.”
Where to start At the risk of stating the obvious, closing the bedroom door, pulling the shades, and turning out the lights all contribute to creating as dark a sleeping environment as possible. Turn an illuminated clock so that the dial faces away from you. If you can’t completely darken your room—because of a nearby street light, for example—try wearing an eye shade to see if it helps.
For extra credit The benefits of sleeping in total darkness aren’t worth hurting yourself by stumbling over something if you need to get up in the middle of the night. So keep a flashlight or low-wattage light at your bedside, just in case. “Unless you need a nightlight to maneuver without injury, it’s best to learn to sleep without one,” Dr. Ash says.
28 Obey your body’s natural rhythms
Why it works Another reason to eliminate artificial night from your bedroom is that it allows your body to stick with its normal sleep-wake cycle. “Inside your brain is a clock of sorts that synchronizes your sleep-wake patterns,” Dr. Ash says. “Light exposure at the same time every day sets this clock, called your circadian rhythm, to ensure consistent sleep and wake times.”
Where to start Stick to a consistent sleep schedule, Dr. Ash advises. “After hours of wakefulness, a sleep-promoting substance builds up in your blood,” she says. “When you maintain a consistent bedtime and wake-up time, the peak level of this substance correlates with the decline in the circadian rhythm for alertness, and you fall asleep. Interplay between these two processes also helps to wake you in the morning.”
For extra credit Rise and shine—literally! Just as darkness is essential to set the “sleep” part of your sleep-wake cycle, light cues your body to ramp up for the day ahead. So don’t stumble around in the dark after your alarm goes off. Open the shades to let in the sun; if you wake before sunrise, turn on your bedside lamp. Artificial light can do the job when natural light isn’t available, Dr. Ash says.
Don’t Worry, Be Healthy
Stress is an inescapable fact of 21st-century life. Whether our stressors are major (losing a job, ending a relationship) or minor (having a fender-bender, meeting a deadline), our bodies answer in the exact same way: Heart rate rises, breathing increases, digestion slows, among many other physiological changes. When stress is a constant, this so-called stress response never switches off. And that isn’t good, especially for our bodies’ defenses.
“The capabilities of the immune system are diminished with frequent activation of the autonomic nervous system, as is the case with chronic stress,” says Jennifer Kelly, PhD, a licensed clinical psychologist at the Atlanta Center for Behavioral Medicine. “The immune system is downgraded so that it can continuously function.”
29 Feel kneaded
Why it works Though research hasn’t established a direct link between therapeutic massage and improved immunity, we can’t think of a better antidote to stress than a little hands-on healing. “When we are under stress, our bodies react by turning off the immune response,” explains Barbara Stone, PhD, the author of Invisible Roots: How Healing Past Life Trauma Can Liberate Your Present. “Only when we’re relaxed does the immune system have a chance to function properly. Massage is wonderful for this.”
Where to start Think of a therapeutic massage not as a splurge but as an investment in your health. Be sure to find a professional with the proper credentials, whether it’s state licensure or national certification (look for the initials NCTMB, which stands for Nationally Certified in Therapeutic Massage and Bodywork). Your doctor or local hospital may be able to recommend someone.
One caveat: You may not be a candidate for massage if you have an active infection, an injury, heart disease, cancer, or if you’re at risk for blood clotting. Not sure if massage is right for you? Ask your doctor before beginning treatment.
Does it work?
Face masks
Good bet (if worn by the person who’s infected)
A face mask serves as a barrier to keep cold and flu viruses from spreading via saliva droplets. “So if you’re sick and you sneeze, your droplets go into the mask and not into the air, which offers protection for the people around you,” says Kathy J. Helzlsouer, M.D., M.H.S., director of the Prevention and Research Center at Mercy Medical Center in Baltimore.
A mask works best if it’s worn by the person who’s sick rather than by someone who’s trying to avoid infection. Don’t expect to be protected from other people’s germs just because you’re wearing a mask, Dr. Helzlsouer says.
For extra credit Dr. Stone recommends the following self-massage technique to relieve stress on the spot:
1. With your right hand, make a circle over your heart in a clockwise direction.
2. If you wish, add a counterclockwise circle on the opposite side of your chest.
3. As you do this, recite statements of self-acceptance, such as, “I deeply and profoundly accept myself with all my problems and limitations.”
30 Learn how to relax
Why it works People who are under constant stress tend to have a hard time relaxing. Both progressive muscle relaxation (PMR) and biofeedback training can help defuse stress’s effects—and boost immunity in the process.
PMR uses a combination of deep breathing and relaxation of the major muscle groups. “It’s known that when you tense and relax your muscles, the effect is more profound than when you just relax,” Dr. Kelly says.
In biofeedback, an external device evaluates various markers of stress—such as heart rate, skin temperature, and muscle tension—and conveys this information to you via visual or auditory cues. The idea is to use these cues to become aware of your physical state and consciously relax, effectively switching off your body’s stress response.
Where to start PMR is easy to do on your own. As its name suggests, it involves tensing and then relaxing each muscle group in sequence, usually starting with your feet and moving up your body to your face. Until you get the hang of PMR technique, you might want to practice to an instructional CD. Many bookstores and libraries carry them.
For biofeedback, training with a licensed therapist is best. One common form of biofeedback involves an electromyograph, or EMG. If you’re using computerized equipment, you’ll see a line on-screen that represents muscle tension. Your job is to move that line, which you do by relaxing your muscles. That’s how you learn relaxation.
For extra credit After you master these techniques, you can move on to others that require less time. One such technique is autogenic training, in which you release muscle tension with deep breathing. “The person creates a feeling of warmth and heaviness throughout the body and thus experiences a state of physical relaxation,” Dr. Kelly says.
31Make time for sex
Why it works When we make love, the brain releases a cascade of love-enhancing, stress-reducing chemicals, explains Frances Cohen Praver, PhD, an author and psychologist in private practice in Locust Valley, New York. Dopamine, for example, fuels our sense of pleasure, while oxytocin and vasopressin contribute to feelings of bonding and attachment.
A healthy sex life may influence immunity in a more direct way. Interesting evidence of this comes from a recent study at Wilkes University in Wilkes-Barre, Pennsylvania, for which researchers collected saliva samples from 112 students. Saliva contains immunoglobulin A (IgA), an antibody that helps protect against infection. The students also reported how often they were having sex. According to the researchers, those in the “frequent” group had the highest IgA levels of any group in the study.
Where to start In the Wilkes University study, “frequent” sex was defined as once or twice a week. That seems to be the optimum number for boosting IgA levels, at least compared to having sex less than once a week or abstaining.
For extra credit Don’t overdo. Interestingly enough, IgA levels were lower among students who were having sex three or more times a week. As we’ve said before, you can get too much of a good thing.
32 Keep a journal
Why it works Think of a journal as your own personal therapist, without the bill. “Keeping a journal allows you to clarify your thoughts and feelings, thereby gaining valuable self-knowledge,” Dr. Kelly says. “It’s also a good problem-solving tool; you might hash out a problem and come up with a solution more easily when it’s on paper.”
Where to start Whether you use an ordinary spiral-bound notebook or a fancy leather-bound diary, what’s most important is to get your thoughts and feelings on paper. Dr. Kelly recommends writing every day, while things are fresh in your memory. Some people like to carry their journals with them and take notes throughout the day.
For extra credit For keeping a journal to be beneficial, you need to write honestly and openly. Express your thoughts and feelings just as you would if you were in a private session with a therapist. “Journaling about traumatic events helps you to process them by fully exploring and releasing the emotions involved, and by engaging both hemispheres of the brain in the process,” Dr. Kelly says. “This allows the experience to become fully integrated in your mind.”
33 Whistle while you work
Why it works By one estimate, as many as two-thirds of us are unhappy with our jobs. That dissatisfaction can spill over into other aspects of our lives. “Constant preoccupation with job obligations often leads to poor eating habits and physical inactivity, resulting in weight problems, high blood pressure, and elevated cholesterol,” Dr. Kelly says.
Yet considering that most of us spend roughly half of our waking hours at work, we need to find ways to make the best of a challenging situation. Otherwise, the stress can overwhelm our immune systems—and calling in sick just adds to the anxiety and tension.
Where to start No matter how unpleasant your work environment, you probably can find a colleague or two to commiserate with and lift your spirits. These relationships can help get you through the toughest times.
For extra credit See the humor in your situation. A study from Canisius College in Buffalo, New York, confirms that humor helps people cope better with on-the-job stress. What’s more, managers who use humor regularly are more effective and have more satisfied employees. If you’re in doubt as to whether a joke is appropriate, always choose the safety of self-deprecation over poking fun at others.
34 Don’t take job stress sitting down
Why it works “Jobs that require us to sit still all day, with very little opportunity to get up and move around, can hurt the immune system indirectly by impeding our ability to exercise,” says Rallie McAllister, MD, MPH, co-founder and medical director of The Mommy MD Guides (www.mommymdguides.com) and a family physician in Lexington, Kentucky. To keep your job from lowering your resistance, fight back with stress-reducing, immune-boosting activities while you’re at work.
Where to start Dr. McAllister recommends taking breaks as often as possible to do a few stretches, go for a short walk, jog up and down the stairs—whatever engages your muscles and short-circuits stress.
For extra credit If you do get sick, stay home! And take precautions to avoid picking up germs from under-the-weather co-workers, including washing your hands frequently and cleaning conference tables, keyboards, phones, and other shared surfaces with disinfectant. (For more strategies to avoid spreading infection in the workplace, see Chapter 3.)
35 Learn to say no
Why it works Women, especially, have a tendency to try to be everything to everyone—spouse, parent, friend, volunteer, the list goes on. In the process, we stretch ourselves too thin and leave too little time for ourselves. We can guess at the outcome: a cluttered, frustrated mind and a depleted immune system.
Where to start Saying no doesn’t mean becoming a negative, nasty person. It’s simply a matter of organizing, prioritizing, and very politely declining what doesn’t fit into your schedule. “Become proficient at saying no to requests that aren’t in line with your priorities,” Dr. Kelly urges.
For extra credit People who have trouble saying no often don’t realize how many obligations they have. So getting a handle on your commitments is an important step toward recognizing what you can and can’t realistically do. “Staying organized and balanced will help you avoid overextending yourself,” Dr. Kelly says. “This will reduce the amount of stress you experience and keep you healthier in the long run.”
36 Flex your mental muscle
Why it works According to Dr. Kelly, stress doesn’t just put a damper on immunity. It can muddle your mind, too, in the form of poor concentration, impaired short-term memory, and reduced productivity. Engaging and exercising your brain is a great way to fend off these negative effects from stress and enhance your immunity in the process.
Where to start Whether it’s reading, doing crossword puzzles, or solving Sudoku problems, Dr. Praver recommends choosing an activity that you really enjoy. “Just make sure that it’s something mentally active, not passive, like watching TV,” she says.
For extra credit Try your hand at online brain games (we’ve posted a few of our favorites at www.prevention.com; click on Health, then on Brain Fitness). The one caveat with these: They shouldn’t leave you feeling frustrated. If they do, they’re just adding to your stress level, Dr. Rabin says.
Smile! It’s Good for You
Remember the toy store slogan that promised shoppers to “turn that frown upside down”? You may want to take it to heart, for the sake of your immunity. According to a research review published in the September 2008 issue of the Journal of Happiness Studies (yes, there really is such a thing!), happy people are less likely to get sick than not-so-happy people. The effect of your mood on your physical health is more than skin-deep: It may increase the number and activity of key immune cells.
37 Maintain your social circle
Why it works As the song lyric goes, we all need somebody to lean on. Having a strong network of family and friends to share the good times and weather the bad can lift your mood—and your immunity. “Social support is as important for health and survival as low cholesterol and not smoking,” says David Spiegel, MD, director of the Center on Stress and Health at Stanford University School of Medicine. “We are social creatures, and the absence of social contact is harmful to mental and physical health.”
Where to start Dr. Kelly believes that you will be happier and healthier if you are constantly making an effort to expand your social network. “The more people you have in your life, the more likely you are to be in truly supportive relationships with at least some of them,” she says. “It’s beneficial to regularly add new people to your circle.”
A good way to do this is to get involved in your community, says Bruce S. Rabin, MD, PhD, medical director of the Healthy Lifestyle Program at the University of Pittsburgh Medical Center. “What’s important is not the number of friends you have in a single social context, but the number of social contexts in which you interact with people,” Dr. Rabin notes. “Family, work, place of worship, book club, volunteer activities, sports activities—all provide opportunities for social interaction.”
For extra credit Choose friends who reinforce your healthy habits. Surrounding yourself with people who support you is beneficial in its own right, but when you work together to be healthier, the effect is even greater. “Make a pact with them to encourage a positive attitude, good eating habits, and healthy choices,” Dr. Gaman advises.
38 Turn on the tunes
Why it works Music puts you in a good mood, which in turn stimulates your autonomic nervous system (ANS) and kicks your immune system into gear. “The ANS can modulate virtually every aspect of immune function,” Dr. Kelly says.
Where to start Tastes in music vary greatly from one person to the next. What matters most is that you listen to what you love. “Jazz, hip hop, classical, rock, country—it’s your personal choice,” Dr. Praver says.
For extra credit Composer Doc Childre recorded the album Heart Zones specifically to facilitate stress reduction and promote emotional balance. Research indicates that it just might work. In one study that compared the effects of 15 minutes of Heart Zones instrumental music against rock, New Age, and a period of silence, Childre’s recording significantly improved immune function, especially levels of the antibody IgA. Heart Zones is available online and through music stores.
39 Watch a comedy
Why it works The simple act of laughing has multiple benefits for your immune system. It lifts your mood, reduces stress, and relaxes you, all of which keep your body’s defenses sharp and primed for action. “Activities that produce deep belly laughter make the immune system more efficient at fighting off upper respiratory tract infections, activating T cells, increasing antibodies, and reducing stress hormones,” Andreula says.
The therapeutic power of laughter has science in its corner. For one recent study, 33 healthy women were divided into two groups. One watched a funny video, while the other watched a tourism video. Across the board, the women in the humor group showed reduced stress and improved immune function, including an increase in natural killer cell activity.
Where to start Make time to laugh each day. Of course, laughter tends to be a spontaneous thing, but you can guarantee at least a few guffaws by watching a funny movie or TV show or listening to a CD by a favorite comedian. “Find things to do each day that are positive and fun,” Dr. Gaman recommends.
For extra credit Yoga is good, and so is laughter, so why not put the two together? “Laughter Yoga is a program developed by a medical doctor in India, and it’s wonderful,” Dr. Stone says. To learn more, visit www.laughteryoga.org.
40 Discover your inner optimist
Why it works Some of us are “glass half-empty” people by nature. But with a bit of effort, it’s possible to cultivate a more positive outlook. “You must consciously think of the good and not the bad,” Dr. Gaman says. “When you catch yourself being negative, look for and verbalize something good about the situation. Over time, you can actually retrain your thought process.”
Where to start Dr. Kelly offers this five-part technique to nurture a more positive mind-set:
Maximize your successes and minimize your failures.
Look honestly at your shortcomings, so you can work on them. Focusing on your strengths can also be helpful.
Keep in mind that the more you practice challenging your thought patterns, the more automatic it will become. It won’t happen right away, but it will become ingrained over time.
Always remember that virtually any failure can be a learning experience and an important step toward your next success.
Give yourself a pep talk. You remember the story of The Little Engine That Could: He powered his way over a mountain that larger engines refused to climb, telling himself “I think I can, I think I can… .” Positive affirmations like this one can help you overcome obstacles, too.
For extra credit While it’s healthy to look on the bright side at least on occasion, you shouldn’t go to extremes trying to change who you are. That tends to backfire. “I’ve worked with a lot of CEO types who try to change themselves, and they end up miserable,” Dr. Moyad says. “They may be driven to work long hours at the office, but that same personality is what makes them plan elaborate vacations and order flowers for their wives.”
Create an Immune-Friendly Lifestyle
Our list would not be complete without the following strategies. Though they don’t fit neatly into any one category, they can improve your chances of staying healthy not just during cold and flu season but all year long.
41 Know your family history
Why it works Your susceptibility to certain illnesses—from colds and flu to heart disease—may have a genetic component. But your genes don’t necessarily have the final say in whether or not you get sick. By being proactive now, you may be able to reduce your risk in the long run.
Where to start Regardless of the ailments that may be tangled in your family tree, the fundamental advice remains the same: Take good care of your body generally, and your immune system specifically. By this point in the chapter, you know what to do!
For extra credit Target your self-care plan to the conditions that most concern you. “If you had a family history of heart disease, you would choose a diet of low-cholesterol foods to protect your heart,” says Shawn M. Talbott, PhD, a nutritionist and author of The Metabolic Method: The Complete Whole-Body Approach to Lasting Fat Loss, Better Mood, and More Energy. “Likewise, if your family has a higher than normal incidence of colds and flu, then exercise, sleep, stress management, and selective supplementation may help reduce the frequency or severity of these illnesses.”
42 Control your allergies
Why it works The sniffling, sneezing, coughing, and wheezing of seasonal allergies are bothersome in their own right. If mounting evidence bears out, allergies might undermine your health in other ways. “Allergies may predispose a person to infection,” Dr. Gaman says. “This is probably due to an overtaxed immune system.” So it makes sense that maintaining tight control of allergies could have a beneficial secondary effect of helping to keep colds and flu at bay.
Where to start To prevent the immune system drain that accompanies an allergy flare-up, the best approach is to avoid or manage your triggers. “Allergies are a form of inflammation, and inflammation is detrimental to the immune system,” Dr. Praver says. “If you have allergies, research your offenders and stay away, or take an anti-allergy medication.”
For extra credit Try quercetin. This powerful antioxidant, found primarily in the peel of apples and the outer layers of red onions, seems to have potent anti-allergy properties. “For folks with allergies, quercetin may be a viable alternative to some over-the-counter and prescription medications,” Dr. McAllister says. “The compound has impressive antihistamine action, making it useful in the treatment of hay fever, eczema, and hives.” To get your daily dose of quercetin, Dr. McAllister recommends heeding this timeless medical advice: Eat an apple a day—preferably a red one.
43 Get a flu shot
Why it works Most cases of seasonal flu could be prevented if everyone who’s eligible for a vaccine actually got one. The vaccine works by introducing a very small amount of the anticipated flu virus strains into your body. In response, your body produces antibodies to those strains. Then if by chance you are exposed to a flu virus, your immune system is ready to respond.
As for rumors that getting a flu shot will give you the flu, they’re not true. Those who happen to develop symptoms after getting vaccinated were already infected with the flu virus.
Where to start The groups at greatest risk for complications from flu—and therefore the leading candidates for vaccination—are children, women who are pregnant, people over age 50, those with chronic health conditions, and residents of nursing homes. The vaccine isn’t for everyone, however. Among those who should avoid it are people with allergy to chicken eggs; those with Guillain-Barré syndrome, an autoimmune disorder; children younger than 6 months; and anyone with an active illness that involves fever.
For extra credit The vaccine against seasonal flu does not prevent H1N1. For that, you will need a separate shot. As of this writing, it is available only to certain populations at high risk for infection. Your best bet is to ask your doctor whether you’re a candidate. You can also get regular, reliable updates on H1N1 and the vaccine supply by checking the website for the Centers for Disease Control and Prevention: www.cdc.gov/h1n1flu/.
44 Show your teeth some TLC
Why it works Think of your mouth as the “check engine” light for the rest of your body. A problem with your teeth or gums might be a sign of trouble elsewhere. The connection between the two isn’t fully understood, but according to Howard E. Strassler, DMD, professor and director of operative dentistry at the University of Maryland Dental School in Baltimore, certain changes in the mouth can be an indicator of diabetes, kidney disease, stomach or intestinal problems, or a lung infection, among other conditions.
Where to start Practice good oral hygiene, including brushing your teeth at least twice a day (morning and night) and flossing at least once a day. “Another simple tip is to change your toothbrush if you have been sick,” Dr. Gaman says. “This will keep you from reinfecting yourself.” And be sure to see your dentist for a checkup every 6 months.
For extra credit Chronic bad breath is another potential signal that something is amiss in your body. “Bad breath due to a medical condition smells completely different than halitosis due to an oral condition,” Dr. Strassler says. “If your breath ever has an unusual odor, you’ll want to see your doctor.”
45 Keep it clean—but not too clean
Why it works A warm, damp, dirty environment is like a “for rent” sign to germs. They won’t feel quite so welcome if you regularly tidy up your living area and workspace. But don’t overdo the fastidiousness, Dr. Spiegel says. “Exposure to pathogens boosts immunity,” he explains. “There is some evidence that autoimmune diseases like asthma may be related to excessive cleanliness. An immune system that isn’t exposed to antigens may turn on its own body.”
Where to start Certain surfaces should be cleaned and disinfected regularly to prevent infection. “The best way to avoid bad bacteria without the overuse of cleaners is to disinfect door handles, phones, and bathrooms at least once a week,” Dr. Gaman says. “During flu season, you should be especially mindful of washing your hands after touching public objects such as door handles and shopping carts.”
For extra credit While being neat can help reduce germ exposure, don’t fret over messes. “Getting hung up on cleanliness will not benefit your immunity,” Dr. Praver says. “If anything, the stress of always cleaning can reduce your immune function.”
46 Winterize your immune system
Why it works There are reasons that seasonal flu is more prevalent in the winter months than at other times of year. For one thing, Dr. Rabin says, the flu virus grows best when body temperature is slightly below normal. That’s more likely to occur as the outdoor temperature falls. For another thing, you’re more likely to be indoors and in close contact with others, which makes spreading germs a whole lot easier.
Where to start As winter settles in, our healthy habits often go into hibernation. Exercise tends to suffer most—not surprisingly, since weather conditions can make outdoor workouts difficult. But staying active is extra-important at this time of year, as it strengthens immune function both directly and indirectly, by boosting your mood. “No matter how exhausted or depressed you are, exercise will make you feel better,” Dr. McAlllister says. “Even a 20-minute walk, three times a week, can help keep you out of a serious slump.”
For extra credit An even easier way to brighten your mood and head off an immune-depleting funk is to get some sun. “Just poking your head out the door or sitting in a sunbeam for a few minutes each day can help break up the winter doldrums,” Dr. McAllister says.
If your winter blues are more persistent and unshakable, you may be dealing with full-blown seasonal affective disorder, a form of depression. In that case, you should see your doctor for proper diagnosis and treatment.
47 Turn down the volume
Why it works Excessive noise can have unexpected consequences for your immune system, mostly by raising your stress level. In European studies, traffic noise was shown to elevate levels of cortisol and other stress hormones, even during sleep. (Cortisol raises blood pressure and blood sugar while lowering immune response.)
Where to start If your work or home environment routinely exposes you to excessive noise, wear earplugs or headphones to help block it. Just be sure that doing so doesn’t pose a safety risk.
For extra credit If the noise level is truly bad, you might want to consider a more extreme measure such as changing jobs or moving. “At least take regular breaks or small vacations from the noise,” Dr. Gaman recommends.
48 Be wary of toxins
Why it works Environmental toxins challenge your immune system just as bacteria or a virus would. So when your body is putting all of its immune resources into undoing the effects of toxin exposure, it doesn’t have much left to keep you from getting a cold or the flu. The most common sources of environmental toxins are household cleaners, impure drinking water, pesticide and insecticide residues on fruits and veggies, and mercury in fish.
Where to start You can reduce your toxin exposure by choosing “green” or natural household cleaners; getting your water quality tested periodically, especially if you have well water; and thoroughly washing produce before eating it (or buying organic). As for mercury, steer clear of king mackerel, shark, and swordfish, which have the highest mercury levels, according to the FDA. Anchovies, cod, clams, and crab have relatively low amounts.
For extra credit Drink lots of water to help flush away toxins and prevent their accumulation in the body’s tissues. Give it a squeeze of lemon for a burst of antioxidants, which help enhance immune function.
49 If you smoke, quit
Why it works Cigarette smoke contains 43 known carcinogens. Knowing the damage that they can do to the rest of your body—heart disease, cancer, and emphysema chief among them—are you truly surprised that they wreak havoc on your immune system, too?
Once you quit, it’s as though every cell of your being breathes a sigh of relief. Respiration, blood pressure, and blood levels of carbon monoxide improve within hours. Your risk of heart attack declines after one day.
Where to start You can improve your chances of quitting successfully by getting rid of all of your smoking paraphernalia—not just cigarettes but lighters and ashtrays, too. Tell everyone in your support network about your plans, so they can encourage you along the way. Try to steer clear of others who smoke, as well as situations that might tempt you to light up.
For extra credit Especially if you’ve tried to quit before, talk with your doctor about nicotine replacement therapy, in the form of patches, gums, lozenges, and sprays. It can help you get past the nicotine cravings and withdrawal symptoms that many smokers say are their main reasons for not quitting.
50 Use antibiotics responsibly
Why it works They certainly have lived up to their reputation as wonder drugs, but if antibiotics aren’t used properly, they can open the door to more serious illness. That’s because bacteria are able to adapt to their environments over time. If they mutate, they can become resistant to antibiotic treatment.
Consider tuberculosis as an example. This bacterial infection, usually of the lungs, is easily treatable with standard antibiotics. But those who contract an antibiotic-resistant strain of TB have a 40 to 60 percent chance of dying from the disease.
Where to start Antibiotics are effective only against bacterial infections. They should not be taken for anything else. (And if your doctor prescribes them to you for something other than a bacterial infection, don’t be afraid to ask why.) If you are given a course of antibiotics, be sure to stay on it for the duration. Your infection may not be entirely gone even if your symptoms have subsided. Don’t save or share antibiotics, and never use them as a preventive measure. They are meant only to treat an active infection.
For extra credit Go easy on antibacterial soaps and lotions. According to the FDA, these products are a major factor in the evolution of antibiotic-resistant bacterial strains. Wash up with plain old soap and hot water instead; it’s just as effective at killing germs.
The Pros Know
Erika Schwartz, MD
Chief medical officer of www.healthandprevention.com
In her 30 years of practice, Dr. Schwartz has taken care of more than 100,000 patients, yet she rarely gets sick. Here’s how she stays healthy:
First, I eat well—lots of fresh fruits and vegetables, no canned foods. I don’t drink alcohol or soda—only water and green tea. I exercise every day and sleep 7 to 8 hours a night.
If I do feel like I’m getting sick, I take some extra steps to fend off whatever is trying to strike. For instance, I won’t exercise that day, and I’ll try to take it easy. Once I get home, I’ll soak my feet in very hot water for 20 minutes. Then I put on a pair of socks and go to bed for 12 hours. Your immune system works much better when it has a way to drain viruses out of your system; putting your feet in hot water induces vasodilation and pulls things out. The Russian Olympic team does this when they are in competition and not feeling 100 percent. I also take about 800 milligrams of an immune booster called lactoferrin for five days.
When I was in my late twenties to mid-thirties, I didn’t have to be as careful. My immune system was in great shape. But as I reached my late thirties and beyond, taking care of myself became even more important.