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Cold, Flu, & Cough Health Center

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Prevent the Flu: Boost Your Immune System

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Looking for some ways to rev up your immune system so you don’t get the flu this year? That’s a great idea. When it’s working well, it can help you avoid illness. But if you let it get run down, you’re more likely to get sick.

Learn what your body's defenses do and how to strengthen them so you can boost your odds of staying well.

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Frequently Asked Questions About the Common Cold

Maybe you're in the grips of a bad cold. Or perhaps you've got big plans coming up and can't afford to get sick. Either way, don't let urban legends be your source on treatment and prevention. We've got your questions covered.

Read the Frequently Asked Questions About the Common Cold article > >

What Is the Immune System?

Simply put, it’s a balanced network of cells and organs that work together to defend you against disease. It stops threats like bacteria or viruses from getting into your body. 

Think of it as a powerful "search and destroy" task force that sends immune-cell forces out to hunt down the unwanted intruders and get rid of them.

How Does It Work?

Your body makes proteins called antibodies that destroy abnormal or foreign cells. They help fend off common ailments like the flu or a cold, and protect you against major illnesses like cancer or heart disease.

You also have a backup response known as the "cell-mediated immune system." This involves immune system cells rather than antibodies. They help your body create memories of past defenses against certain threats.

When your body sees that invader again, it calls up that memory and sets out to destroy the threat before the disease develops. This is what makes vaccines or immunizations work for illnesses like the flu, measles, chicken pox, or hepatitis. The shot has a small but harmless amount of the disease in it so your immune cells can react, learn, and remember how to protect you from it next time.

Do Lifestyle Changes Help?

Yes. Bad health habits can slow your immune system. That’s why doctors urge you to make certain lifestyle changes.

To get started, lower your stress -- it's the most important change you can make. A steady flow of stress hormones makes it hard for your body to keep you well. Relaxation techniques, daily exercise, and stress-management techniques can all help.

Next work on getting enough sleep.You need 7 to 8 hours of shut-eye each night to boost your defenses.

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