The most surprisingly basic and everyday habits can influence how well your body fends off colds, flu, and other infections, from not getting enough sleep to not keeping a pen in your bag.
Here's a list of little things you may be doing (or not doing) that can make you sick.
Not Socializing Enough
Believe it or not, research shows that the fewer human connections we have at home, at work, and in the community, the likelier we are to get sick, have more anxiety, and live shorter lives.
In one study, researchers who monitored 276 people between 18 and 55 found that those with six or more connections were 4 times better at fighting off the viruses that cause colds than those with fewer friends.
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What to do: Don't let a jam-packed workday or hectic schedule get in the way of your friendships. Stop by a co-worker's office for a quick Monday morning catch-up, or e-mail/text your friends at night to stay in touch when you're too busy for phone calls.
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Not Getting Enough Rest
The perfect example: college students who get sick after pulling all-nighters and cramming for exams. Poor sleep is associated with lower immune system function and reduced numbers of killer cells that fight germs. In fact, the University of Chicago researchers found that men who had slept only 4 hours a night for 1 week produced half the amount of flu-fighting antibodies in their blood (jump-started by a flu shot) compared with those who slept 7 1/2 to 8 1/2 hours.
What to do: Most adults need between 7 and 9 hours of uninterrupted rest every night, but how you feel in the morning and throughout the day may be a better gauge. If you're tired when you wake up in the morning, you're not getting enough—sleep, or maybe not enough quality sleep.
Being A Pessimist
Yes, your attitude affects your immune system too. Studies show that glass-half-empty types don't live as long as those who look on the bright side. When pessimists put a more positive spin on the calamities in their lives, they have less stress and better health. A classic UCLA study found that law students who began their first semester optimistic about the experience had more helper T cells mid semester, which can amplify the immune response, and more powerful natural killer cells, than students who had a more pessimistic perspective. One reason could be that optimists take better care of themselves. It could also be due to less stress-related damage to the immune system, such as killer cells that suddenly become pacifists.
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What to do: Try striking up a dinner table conversation with your family, where you all share a couple of good things that happened every day.
Taking Too Many Antibiotics
Taking antibiotics at the first sign of a sniffle can make you resistant to these drugs over time, causing more serious infections.
Researchers found that certain patients taking antibiotics had reduced levels of cytokines, the hormone messengers of the immune system. When your immune system is suppressed, you're more likely to develop resistant bacteria or become sick in the future.
What to do: Take antibiotics only for bacterial infections, use them right away, and take the entire course. Don't use antibiotics preventively unless prescribed by your doctor, and don't save or share unfinished courses.
Holding Your Emotions In
A constructive argument with your spouse can actually increase immunity, say UCLA researchers. They asked 41 happy couples to discuss a problem in their marriage for 15 minutes. The researchers detected surges in blood pressure, heart rate, and immune-related white blood cells, all of which were similar to the benefits seen with moderate exercise. But you still have to play nice: Couples who frequently use sarcasm, insults, and put-downs have fewer virus-fighting natural killer cells, have higher levels of stress hormones, and take up to 40% longer to recover from injuries than those who manage to stay positive and affectionate during their quarrels.
What to do: Don't keep what's bothering you bottled up. People with type D personalities—those who keep their opinions and emotions hidden—have killer T cells that are less active than those found in more expressive peers.
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Stressing Out Too Much
Chronic stress—the day-after-day kind you experience over job insecurity or a sick relative—takes a toll on many aspects of your health, including immunity.
There is compelling scientific evidence that this kind of stress (as opposed to the every-now-and-again kind from a bad day at work or a screaming match with your kid) causes a measurable decline in the immune system's ability to fight disease. Periods of extreme stress can result in a lower natural killer cell count, sluggish killer T cells, and diminished macrophage activity that can amplify the immune response. In fact, widows and widowers are much more likely to get sick during the first year after their spouse dies than their peers who have not experienced a major loss.
What to do: Do more of the things that help you relax. Take a hot bath, run on the treadmill, take a relaxing yoga class, or bake a dessert. The important thing is that you unwind and recover from stress, since it's often hard to avoid in the first place.
Not Having A Pen With You
That's right, having your own supply of pens might just keep you from picking up a virus. Cold and flu germs are easily passed through hand-to-hand contact, says Neil Schachter, MD, a professor of pulmonary medicine at Mount Sinai School of Medicine and author of The Good Doctor's Guide to Colds and Flu. Any way you can avoid touching public objects—such as the communal pen at the bank—will cut your risk.
What to do: "When you get up in the morning, don't leave the house without a pen in your pocket or your purse," Schachter suggests. "Take your own wherever you go, and use it instead of the doctor’s, the delivery guy’s, or the restaurant waiter’s."
Not Exercising Enough
One in four American women doesn't exercise at all—and that's an easy way to set yourself up for sickness. When researchers compared inactive people with those who walked briskly almost every day, they found that those who didn't walk took twice as many sick days in 4 months as those who strolled regularly.
What to do: Experts say that it takes 30 minutes of aerobic exercise—a brisk walk counts—to sweep white blood cells back into circulation, making your immune system run more smoothly. We don't need to tell you that puffing ciggies is terrible for the entire body. But the secondhand kind is almost as harmful.
Not Laughing Enough
Researchers have found that the positive emotions associated with laughter decrease stress hormones and increase certain immune cells while activating others. In a study conducted at Loma Linda University School of Medicine, healthy adults who watched a funny video for an hour had significant increases in immune system activity.
What to do: Let yourself laugh more! Watch your favorite comedies, have lunch with a pal known for their funny bone, and actually read those silly email jokes from friends.
