The connection between the immune system and stress is one that has been long recognized. If not you, then most certainly many people you know can relate to the experience of coming down with a cold or flu after being stressed out, whether it’s due to work, family, or a major life change.

In truth, the connection is a complex interaction between various processes in your body involving the immune system, hormonal system, and central nervous system (CNS, for short). The emotional weight of stressful situations can throw off the function of this intricate network of systems.

How the Immune System Works

The initial response of your immune system to a stressful event is actually designed to protect your body and maintain your health. Since your brain (part of the CNS) perceives stress as a danger, it sends signals through the hormonal system to move immune cells to areas of your body most likely to be injured.

In the case of a wound, the immune cells are directed to the skin. They also move into the lungs, as well as the urinary, reproductive, and gastrointestinal tracts in case you need to fight infection. This movement of immune cells is one example of how stress stimulates your immune system in the short-term. It is the appropriate biological response adapted by humans to ensure survival when acute stress—one lasting minute to hours—occurs.

Be aware, however, that there is a downside to this acute response. If you have an inflammatory condition like hay fever or atherosclerosis (hardening and narrowing of arteries), or if you have an autoimmune disease like psoriasis or rheumatoid arthritis, triggering increased immune activity could be harmful to your body.

The Effect of Chronic Stress on the Immune System

When stress becomes chronic, meaning you’ve been in stressful situations for weeks or even months without adequate relief, the immune system can then become suppressed. One explanation for this effect is that chronic stressors cause a prolonged or repeated activation of the pathway which produces cortisol, the stress hormone. So much cortisol gets formed that the cells which are supposed to recognize the hormone end up shutting down and become resistant to it.

Research on individuals under chronic stress has shown that they are more susceptible to catching colds, have delayed wound healing, and mount a weaker immune response to vaccination.

6 Ways To Relieve Stress

Giving your body adequate relief from the negative effects that life’s stressors can bring is essential to maintaining your health and keeping your immune system functioning effectively as your guardian and protector. There are several strategies to alleviate the stress in your life.

1. Take a Break

Sometimes you just need to step away from the activity that is creating tension. If you’re able to take a break from your stressor, then you may be able to prevent overwhelm and perhaps come back to a stressful, but necessary, endeavor with a fresh perspective that is more positive and productive.

2. Get Enough Restful Sleep 

There was a 2009 study that showed that people who slept less than seven hours each night were three times more likely to catch a cold. Research has also found that sleep can improve the immune response to a vaccine and may even help T cells capture their targets. You can think of T cells as the soldiers of your “immune army” in your battle against infection.

3. Laugh

Laughter is a fun way to boost your immune health. Not only can it ease your stressed mental state, it can also create physical changes in your body.

Laughter has been shown to lower levels of cortisol and adrenaline (the stress hormones). It can also boost immune cell and antibody activity. While initially stimulating your stress response, including heart rate and blood pressure, a good laugh reduces these factors, allowing you to settle into a more relaxed feeling. Moreover, when you laugh, the brain is triggered to release endorphins, the “feel-good hormones.”

4. Exercise

Regular exercise benefits your mind as well as your body. It reduces stress hormone levels and it signals the production of endorphins. Except for when you are ill, you can exercise for stress relief nearly every day. Almost any type of exercise will provide some benefit.

A good goal is to do 30-40 minutes of moderate exercise, such as walking, per day. If you’re not able to complete a full 30 minutes in one session, you can break it up into 10-15-minute chunks. You may also choose to do more vigorous exercise for 15-20 minutes per day.

5. Meditate

Mental stress can manifest in your body in various ways. It may increase your heart rate, raise your blood pressure, and speed your breathing. By exercising your mind through meditation, you can relax your body.

Studies on yoga masters have shown that meditation can decrease heart rate, lower blood pressure, slow down breathing, reduce the body’s consumption of oxygen, and even change skin temperature. When you meditate, you can lower your cortisol and adrenaline levels and decrease inflammation. Start with 10-15 minutes of meditating 3-4 times per week.

6. Perform a Breathing Exercise

By focusing on your breath, you can learn to calm your mind and body. Here are a few techniques you can try.

  • Mindful breathing: Simply become aware of your breath and turn your focus on it. Don’t worry about trying to change the way you breathe. When you focus on your breath, your body generally slows down the breathing pattern so that you can feel more calm. As your mind stays centered on the movement of air through your nose and mouth, going in and out of your lungs, it can feel like a relaxing meditation.
  • Belly breath: This type of breathing has a built-in self-check. Lay on your bed or a reclining chair, then put the palm of one hand flat on your abdomen and place the other hand on your chest. As you breathe, feel your body inhaling and exhaling air by noting the movement of your abdomen. Make sure that the hand on your chest is not the one going up and down. Note that as you exhale, you contract the abdominal muscles and squeeze the air out of your lungs.
  • 4-7-8 Breath: Anne Kennard, DO, FACOG, is a board-certified obstetrician-gynecologist, fellowship-trained in integrative medicine who recommends the 4-7-8 breath as a method “that someone could use to decrease stress quickly.” She learned the technique from her mentor Dr. Andrew Weil who developed it using pranayama (yoga breathing) as a foundation.

“To decrease the stress response, the exhale needs to be lengthened compared to the inhale,” says Dr. Kennard. To perform the 4-7-8 breath, you should first inhale for a mental count of 4. Then, hold your breath for a count of 7. Finally, exhale for a count of 8.

According to Dr. Kennard, “The person will start to notice their physiology change rapidly. It only takes about 4 rounds.” 

“That’s a great [breathing exercise] for morning… or before bed, or any time the world starts to feel a little bit overwhelming,” she explains. “You’ll feel better, your immune cells will work better, and you’ll sleep better.”

Foods and Supplements For Stress Relief

Vitamin C 

Vitamin C can help defend you against the negative effects of stress. Researchers in Germany found that those who took Vitamin C had lower blood pressure and lower cortisol compared to those who did not after being given tasks like presenting a speech and doing difficult math problems.


Quercetin is an anti-inflammatory compound that can help inhibit the production of cortisol when you are stressed. Take it as a supplement or find it in foods like apples, bell peppers, green tea, and red onions.


Selenium is a mineral that can be helpful to relieve anxious feelings you may have when you are stressed. It is available in supplement form and can also be found in foods such as seafood (especially fish), organ meats (like liver and kidney), and Brazil nuts. When choosing a supplement, look for "selenium glycinate" in the ingredients as it has a high level of absorption in your gut.


Magnesium is another mineral that can be very calming. It is able to act on the blood-brain barrier, preventing stress hormones from entering the brain. Choose a supplement or eat foods like celery, spinach, avocado, and dark chocolate.

Omega-3 fatty acids 

Omega-3 fatty acids have many health benefits. One such benefit is helping to reduce the production of stress hormones. Omega 3s are found in foods like walnutscashews, grass-fed beef, and fatty fish (including tuna and salmon). When choosing a supplement, make sure you see the most important fatty acids, EPA and DHA, on the ingredient list.

Remember, it’s always wise to check with your healthcare provider before starting a new supplement. This is an especially good idea if you have a medical condition or are taking any medications.