Given your immune system's role as protector against illness, you want to do all you can to give it a boost. I’ll help you separate myth from fact so you can learn how to keep your immune system in top shape.

FACT: Stress makes you more vulnerable to illness.

Ongoing stress, such as being in a difficult relationship, living with a chronic disease or taking care of someone with a serious condition, can make you more susceptible to illness, from the common cold to chronic disease.

Reducing the amount of stress in your life -- and improving your ability to cope with the stress you can't escape -- will help. Even something as simple as deep breathing or meditation can lessen the effects of stress.

Flu Season Is Here

Get vaccinated before peak flu season hits - 4 easy ways to get your flu shot with Ochsner.

MYTH: Getting a flu shot weakens your immune system and makes you more likely to get the flu.

Actually, the opposite is true. Getting a flu vaccine provides your immune system with help. A flu vaccine contains a dead or weakened virus that cannot infect you with the flu, but does teach your immune system to recognize that virus as a threat.

While some people may still get the flu after having a flu shot, they'll probably have a milder form of the illness. Some may mistake the occasional side effects of the vaccine (fever, aches) for flu symptoms when it’s more likely to come from another unrelated bug.

FACT: What you eat has an effect on your immune system.
Although there isn't one food that will provide an instant boost to your immune system, developing the habit of eating a balanced, healthy diet with a variety of foods keeps your immune system in good shape.

• Eat more antioxidants. Studies show that people who eat more antioxidants in their diet may be better protected against some kinds of cancer. Increasing the amount of fruits and vegetables in your diet is the optimal way to get antioxidants such as vitamins A, C, E and flavonoids.
• Eat less saturated fat. Some studies show that diets high in saturated fat can suppress the immune system. Keep fat to 30% of your overall calories, and opt for healthier fats -- omega 3 fatty acids.
• Drink tea. Green tea contains powerful antioxidants called catechins, which studies show may help protect against cancer as well as the common cold. One 6 oz cup is more than enough.

FACT: Your immune system gets weaker as you grow older.
As you age, your ability to fight infections diminishes. Older adults are more likely to get sick from infections. Infections, such as flu and pneumonia are more likely to be fatal. Studies show that people over 65 also have a lower response to vaccines. While there are multiple theories as to why this happens, we really are not sure.

MYTH: Running a fever when you're sick weakens your immune system.
A fever can help your immune system fight infections in two ways. A higher temperature in the body speeds up the functioning of cells that fight illness. Higher temps also make it harder for invading microbes to reproduce and multiply.

Always call a doctor for unexplained fever in infants and children. If you've had a fever for more than two or three days or your temperature is greater than 103 Fahrenheit; call your doctor. Anyone with a suppressed immune system should be seen immediately if they have a fever.

FACT: Allergies are caused by an overactive immune system.
Allergy symptoms occur when your immune system reacts to a normally harmless substance such as pollen, pet dander, or mold. Your body sees the allergen as a dangerous invader and attacks it, causing the familiar runny nose and itchy eyes. Allergies are treated by avoiding your allergy triggers and taking medication to control symptoms.

FACT: Researchers are working on vaccines that can boost the immune system response to cancer.
The immune system can have a hard time recognizing cancer cells as invaders, because the cells come from inside the body itself. In other cases, the immune system does recognize cancer cells as abnormal but is too weak to fight them off. Scientists think a less- efficient immune system may be partly responsible for the fact that risk of cancer goes up as you age.

Researchers are working on ways to restore and harness the immune system's power to use against cancer cells through treatments known as biological therapies (or immunotherapy). Cancer vaccines are one kind of biological therapy.

Some vaccines are designed to prevent cancer (such as Gardasil, which helps prevent cervical cancer that is caused by certain viruses). Others are designed to treat existing cancers by "re-educating" the immune system to recognize tumor cells as foreign invaders that need to be destroyed.