What Is the Immune System, and Why Is it Important?

The immune system is your body’s first line of defense against illnesses coming from bacteria, viruses and fungi. It helps protect you from infections and illnesses, keeping you healthy and functioning.

In this blog, we’ll explore the fundamentals of immunity and share proven strategies you can adopt to strengthen your body’s natural defenses.

Can stress weaken my immune system?

Yes, ongoing stress can weaken your immune system, increasing your risk of developing the common cold and chronic diseases. Stress from relationships, chronic illness or caregiving can lower immunity.

How to reduce stress:

Practice deep breathing or meditation to lower stress levels
Incorporate stress-reducing activities like yoga, exercise or journaling into your routine
Seek support from friends, family or a therapist when needed

Does getting a flu shot weaken my immune system?

No. The flu vaccine strengthens your immune system by helping it recognize and fight the virus. It contains a dead or weakened virus that cannot infect you, but helps your body build immunity. Some people may still get the flu after the shot, but symptoms are usually milder. Getting a flu shot is a personal decision and should be discussed with your doctor or healthcare provider.

Key points about the flu shot:

While you may still get the flu after vaccination, symptoms are usually milder
Flu shot side effects like mild fever or aches are not the flu, but a sign your immune system is responding to the vaccine

Can food boost my immune system?

No single food instantly boosts immunity, but a balanced diet with fruits, vegetables and healthy fats helps support it.

Does aging affect the immune system?

Yes, as you age, your immune system becomes less effective at fighting infections. Older adults are more susceptible to illnesses like the flu and pneumonia, and these infections are more likely to be severe or even fatal.

What you can do:

Maintain a healthy lifestyle by exercising, eating a balanced diet and getting enough sleep.
Consult your doctor about ways to strengthen your immune system as you age.
Stay up to date on vaccinations, including flu and pneumonia shots. Getting vaccinated is a personal decision and should be discussed with your doctor or healthcare provider.

Is a fever bad for my immune system?

Contrary to popular belief, a fever is actually a sign that your immune system is working hard to fight off an infection. Higher body temperatures accelerate immune cell activity and make it more difficult for microbes to multiply.

When to call a doctor:

If a fever lasts more than two to three days.
If your temperature exceeds 103 degrees.
For infants, children or individuals with weakened immune systems, seek medical attention immediately for any unexplained fever.

What causes allergies?

Allergy symptoms are caused by an overactive immune system that mistakenly identifies harmless substances (like pollen or pet dander) as threats. This triggers symptoms such as sneezing, itchy eyes, and a runny nose.

How do you manage allergies?

Avoid known triggers whenever possible.
Use medications such as antihistamines or nasal sprays to manage symptoms.
Consult an allergist for personalized treatment options if symptoms are severe, persistent or debilitating.

Are researchers working on ways to boost the immune system against cancer?

Yes, immunotherapy is a cancer treatment strategy that has already revolutionized treatment of certain cancers. Examples of immunotherapy treatments include checkpoint inhibitors (immune cell boosting medicines), cancer vaccines and adoptive cell therapy. The immune system sometimes struggles to recognize cancer cells as threats because they originate from the body itself, but these treatments retrain the immune system to recognize and attack cancer cells.

Types of cancer vaccines:

Preventive vaccines: Gardasil, which protects against HPV, a virus linked to cervical cancer
Therapeutic vaccines: These vaccines "re-educate" the immune system to recognize and destroy cancer cells

Can I boost my immune system with supplements?

While some supplements, like vitamin C or zinc, may support immune health, they are not a substitute for a healthy lifestyle. Focus on a balanced diet, regular exercise, adequate sleep and stress management for optimal results.

Your immune system is a complex and powerful defense mechanism, but it requires your support to function optimally. By reducing stress, eating a balanced diet, staying up to date on vaccinations and understanding the facts about immunity, you can help it stay healthy.

If you have questions about your immune system or need personalized advice, consult a healthcare professional today.