Researchers have confirmed that stress can negatively impact your immune system. To fully understand how stress affects your immune system, let’s explore how your immune system works, what happens to your bodies when it’s stressed, how to manage stress and how to boost your immune system.

Immune System

The immune system is your body’s defense system and essential to your survival. To function properly, your immune system must detect invaders, such as viruses, and distinguish them from your own healthy cells. 

Parts of the Human Immune System

Mucous Membranes:

Mucous membranes secrete mucus, which has protective antibodies. Mucous membranes are in the areas which are prime entry points for invaders: mouth, nose, eyelids, windpipe, and lungs. 

Tonsils:

Your tonsils stop invaders entering your body through your mouth or your nose as they contain a lot of white blood cells responsible for killing germs.

Lymphatic System:

Your lymphatic system is a network of vessels and nodes that transports and filters lymph fluid containing antibodies and white blood cells.

Thymus:

Some of your white cells mature in the thymus.

Lymph Nodes:

Lymph nodes are where white blood cells sample information brought in from your body. If they recognize invaders, they will eliminate the invaders.

Spleen:

Your spleen processes information from your bloodstream. White blood cells are enriched in specific areas of the spleen, and upon recognizing invaders, they will respond accordingly.

Bone Marrow:

Your bone marrow contains stem cells that can develop into white blood cells that are important first-line responders to infection.

Key Player in the Immune System

White Blood Cells:

White blood cells are on constant patrol, looking for invaders. Once an invader is found, the white blood cells eliminate it. White blood cells also remember each novel invader encountered, so as to more quickly eliminate future attacks by that invader.

Supporting Players: 

Skin:

The skin is usually the first line of defense. Skin cells produce important antimicrobial proteins. In addition to the mucous membrane, tears and saliva protect your body where there are openings in your skin as they contain an enzyme that breaks down the cell wall of many bacteria.

Lungs:

In addition to enabling us to obtain needed oxygen and getting rid of carbon dioxide, our lungs have an important immunity role.  Mucus is secreted which keeps the airways moist and traps unwanted particles that have been inhaled. The lungs remove unwanted debris by either sending it to the gut or coughing it out. The lungs also contain specialized white blood cells that destroy foreign particles in the lungs. 

Digestive Tract:

Your gut has to deal with the pathogens in everything you ingest.

Innate immunity

We are all born with some level of immunity, such as skin and mucous membranes. If an invader manages to dodge the innate immune system, adaptive or acquired immunity kicks in.

Adaptive (acquired) immunity

This develops as we go through life. As we are exposed to diseases or get vaccinated, we build up antibodies to different invaders. An immunization introduces weakened invaders in such a way that we do not become sick but still produce antibodies. Because your body saves copies of the antibodies, it is protected if the threat should reappear later in life.

Mind-Body Connection with Immune System

Do different mental states affect how our bodies function? Emerging evidence is supporting a mind-body connection. In recent years, research has suggested that emotions like stress and worry, when they persist long-term, can negatively affect our immune system. As seen in research with college students, chronic feelings of stress reduce our immunity.

The Good, the Bad and the Ugly of Stress and Cortisol

When you hear the word stress, do you think all stress is bad? Stress can be good.  Examples of good stress include physical stress on muscles or your vascular system when exercising, alertness in response to psychological stress such as taking an exam or pay attention to driving during bad weather.

One of the main hormones released under stressful conditions is cortisol. Cortisol mobilizes a “fight-or-flight” mode, increasing blood pressure and heart rate. 

When your body encounters an invader, your immune system responds. Part of this response causes inflammation, which is often a good thing (it means your immune system is working). Another interesting property of cortisol is that it acts as an anti-inflammatory signal, meaning that it acts as an “off switch” for your immune system’s inflammatory response.

Having cortisol turn off your immune system in response to a short-term issue, say being chased by a saber-toothed cat or taking a final exam, is good. The problem arises when chronic stress becomes your norm.

If you are stressed for a long time, your body never gets the signal to return to normal functioning. This can weaken your immune system, leaving you more vulnerable to viral infections and frequent illnesses. Your regular vaccines will not work as well if you have chronic stress.

How Chronic Stress Affects Your Immune System

Chronic stress can negatively impact many of your body systems, from muscular to cardiovascular. Researchers have found evidence that 75% to 90% of human disease is related to chronic stress and inflammation. While short term suppression of the immune system is not dangerous, chronic suppression leaves the body vulnerable to infection and disease. For a vaccine to work, there needs to be both antibody and virus-specific white blood cell response. Changes in the immune response by chronic stress can negatively impact both antibody and white blood cell response to viral vaccines.

Ways To Boost Your Immune System

• Stress reduction: Practice stress reduction strategies regularly.
• Sleep: Practice good sleep hygiene and maintain consistent sleep hours.
• Exercise: Moderate, regular physical activity helps to boost immune system function by raising levels of infection-fighting white blood cells and antibodies, increasing circulation, and decreasing stress hormones. 
• Nutritious foods: Eat plenty of fruits and vegetables. Include fermented vegetables or other probiotic-containing foods.
• If you smoke, stop smoking.
• If you drink alcohol, only drink in moderation.
• Take steps to avoid infection, such as washing your hands frequently and cooking meats thoroughly.
• Take the appropriate supplements for your body. A functional medicine practitioner can help you identify the supplements you need.

Stress Reduction Strategies

• Exercise regularly
• Reduce or eliminate caffeine
• Aromatherapy
• Keep a journal
• Spend time with friends, family, and pets
• Laugh daily
• Deep breathing, meditation, yoga
• Take a bubble bath or sauna
• Get a massage
• Set boundaries and say no
• Listen to music
• Be creative
• Talk with a therapist

Understanding the role chronic stress plays in compromising your health should inspire you to take charge in lowering your stress. Find the stress-reduction strategies which work for you and employ them daily. Implement the steps to boost your immune system. Your future self will thank you.

To your health.

Dianne Hinton NP, PA, IFM-C