My definition of psychoneuroimmunology is “how stress and sadness make you sick.” Technically, the formal definition is, “a branch of medicine that deals with the influence of emotional states (as stress) and nervous system activities on immune function in relation to the onset and progression of disease.” We now know that the immune system communicates with the brain and that these signals impact behavior, thought, and mood.
As you know, when you get sick or injured, you might develop a fever, lose your appetite, not get as thirsty, have no interest in sex, and become anxious. These symptoms result from the pro-inflammatory molecules created by your immune cells, which then act inside of your brain. If these pro-inflammatory molecules are inactivated in animals, they show no signs of physical sickness after they’ve been purposefully infected with an illness.
Now think about a time when you or someone that you know suffered severe stress or depression – loss of appetite, loss of libido, increased anxiety? Likely the case. A lot of the symptoms that we have when we are ill or injured are the same symptoms that we have when we are in psychological distress.
If an animal is put into social isolation (an extremely stressful situation for them) or they are given electrical shocks, they will form A LOT of those pro-inflammatory molecules. They will also develop those symptoms discussed above (loss of appetite, anxiety, etc.). In short, an animal that is purposefully stressed will develop symptoms akin to physical illness.
Being stressed for a brief period of time (like if you’re being chased by a lion), suppresses cellular immunity against things like viruses, but humoral immunity (against stuff outside of the cells like parasites and bacteria) is unaffected. However, chronic stress weakens both types of immunity. And in modern times, we are much more likely to suffer from chronic stress than we are to be chased by a lion.
How much stress increases your risk of illness depends on many things, including your other risk factors, lifestyle, and coping style. Chronic stress leads to a litany of health problems that many of us can relate to anxiety, depression, digestive problems, headaches, heart disease, sleep problems, weight gain, and trouble remembering things and concentrating.
If you feel like stress is a problem in your life or believe that you feel sick more often than the average person, you might want to try these things:
- Exercise, or at least stretch, whenever you can (even if it’s just to do 10 jumping jacks while you wait for the coffee to finish brewing)
- Get a massage, practice deep breathing, or do anything else that deeply relaxes you
- Stop watching television and looking at your computer or phone screens 30-60 minutes before turning in for the night
- Take time for your hobbies (if you can’t think of a hobby that you enjoy, you are almost certainly burnt out)
- Force yourself to hang out with the people you love, even if you don’t feel like it or believe that you don’t have time
- Track your level of stress and your daily activities to help you to find patterns, some of which you might be able to actually do something about
- Try to avoid processed foods, refined carbohydrates, and sugary snacks when you feel stressed…they are only going to make things worse (put down the Captain Crunch). At least as important as what you eat is how you eat, and learning about mindful eating is something that I recommend for pretty much everyone.
- Think about the people around you – what kind of stress could the cashier be experiencing, why might that special someone be so angry all of the time, and why do some people get so nasty around the Holidays every single year? You might feel better, and less alone, by keeping in mind that all of us have stressful, crappy, days.
- Make a point to remember other times in your life that you’ve been super-stressed, and how it eventually got better
- Tune in to your senses and make them happy – listen to music that you like, wear clothes that are comfortable for you, try some essential oils or surround yourself with other aromas that are pleasing to you, etc.