Myths vs. Facts About Your Immune System

Medically Reviewed by Brunilda Nazario, MD on November 07, 2013
4 min read

Your immune system is your friend. It protects your body from infection. Give it your full support and, as with any friend, there will be perks.

Here’s how it works: Your immune system creates, stores, and distributes the white blood cells that fight bacteria and viruses that enter your body, especially during cold and flu season.

For such a simple-sounding process, there's a lot of bad information out there. Here are some myths and facts about the immune system and how it works.

Fact. Mom and dad were right when they told you to eat your fruits and vegetables. Studies show that people who eat a lot of them get sick less. The nutrients in them can help your immune system fight viruses and bacteria.

Myth. There's a strong link between sleep and a healthy immune system. But not just any sleep will do. Restorative sleep, which means enough sleep to get the body back into fighting shape, is key.

Sleep needs vary by person, but most adults need 7-8 hours a night. Teens need 9-10 hours, school-aged kids need at least 10 hours, preschoolers need 11-12 hours, and newborns need 16-18 hours.

Over the past few decades, though, the average time asleep has dropped to less than 7 hours a night for adults. If you sleep less than your body needs, you’ll build up a sleep debt. And you can't make that up with naps or by sleeping in on weekends. Bottom line: Get to bed at a time when you know you can sleep at least 7 hours.

Fact. A good outlook may be good for your health. One study of law students showed that their immune systems kept pace with their thoughts about how tough school would be. When they felt better about school, they had a better immune system. When they were worried, their immune system slowed. The upshot: Looking on the bright side might better equip your body to fight illnesses.

Fact.Coughing, sneezing, or even talking near someone who has the flu can make you sick when droplets of the virus get into the air. And you can inhale these droplets even if you are 2-3 feet away. If you’re the person who’s sick, stay home. If you must be around others, cover your mouth and nose when you cough or sneeze into your shoulder or the inside of your elbow. If you’re healthy and suspect others around you are sick, stand at least 4 feet away. Also, since germs can live on hard surfaces like doorknobs for hours, wash hands frequently, and keep them away from your face.

Myth. Taking a daily multivitamin is probably a good idea to stay healthy if you eat poorly. But taking megadoses of a single vitamin or supplement has not been proven to help the immune system.

Myth.Vitamins and minerals matter for kids too, but they should get them from eating nutritious foods. If your child is a picky eater, a vegetarian, or a vegan, your doctor may recommend a supplement. Remember: Though you can buy children’s vitamins over-the-counter, they are still drugs. Taken excessively, they can be toxic.

Fact. Do you cringe when you see a parent pick up a baby’s pacifier and suck it before returning it to the baby’s mouth? Don't. A recent study found that parents who suck their infant’s pacifier may lower the baby’s risk of having allergies. The thought is that germs transferred to the infant from the parent’s saliva will kick-start the baby's immune system.

Myth. While there’s no direct link between moderate exercise and keeping the average person’s immune system humming, there are lots of benefits to working out. Among other things, it lowers blood pressure, keeps body weight under control, and can protect you from certain diseases. So get moving.