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 who didn't walk took twice as many sick days in 4 months as those who strolled regularly.
Experts say that it takes a 30 minutes of aerobic exercise—a brisk walk counts—to sweep white blood cells back into circulation, making your immune system run more smoothly.
Your Friends Smoke
We don't need to tell you that puffing ciggies is terrible for the entire body. But the secondhand kind is almost as harmful.
Each year, because of exposure to tobacco smoke, an estimated 3,000 nonsmoking Americans die of lung cancer and 300,000 children suffer from lower respiratory-tract infections. Secondhand smoke can trigger an asthma attack and aggravate symptoms in people with allergies. In addition, tobacco smoke has been shown to make asthma worse in preschool children and may even cause it.
Sounds obvious, but avoid secondhand smoke as much as you can -- including spending time with people while they smoke. Encourage anyone in your everyday life (husband, coworkers or neighbor friends) to quit.
You Always Reach for 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.
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.
You're Little Miss Serious
Consider this a doctor's note to troll YouTube on your lunch break...
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.
Um, laugh more. You know how: Watch your favorite comedies, have lunch with a pal known for her funny bone, and read those silly forwards from friends before you auto-click "delete."
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