I clearly remember one of the very first lectures I attended in psychology. I think we all have a general sense that a healthy body and mind are linked, but this lecture presented such simple evidence that I was really blown away. My lecturer presented the study conducted by Cohen et al (1991), which took nearly 400 healthy people, assessed their stress levels, and then exposed them to respiratory viruses. The results were clear. Those people with high stress got sick. Those with little or no stress fought off the virus and did not fall ill. You couldn't get much simpler or direct evidence that the state of your mind has a direct and considerable effect on the state of your body.
Looking further into the relationship between emotion and illness it is possible to see numerous examples of the emotional state affecting the physical. You could quite literally write a whole book on this subject, so this article aims to serve as a brief introduction rather than an attempt to cover everything!
Firstly, let us consider the difference between psychogenic illness and somatogenic illness. Somatogenic illness is one in which the emotional disturbance or trauma has made the body more susceptible to physical threats, such as microbial infections or degenerative processes. Psychogenic illness is not caused by any other agents such as bacteria, but rather results when the emotional trauma is so severe that the other bodily systems begin to shut down.
Somatogenic illnesses include ulcers, high blood pressure, and rheumatoid arthritis.
Experiencing stress can cause the body to release norepinephrine and cortisol, repeating this time again as a response to ongoing emotional trauma leaves the immune system weakened and compromised, and thus more vulnerable to the onslaught of passing bacteria or viruses. A person with too much norepinephrine in his system will experience dizzy spells, shortness of breath, sweating and increased heart rate. The elevated norepinephrine levels contribute to the formation of peptic ulcers by stimulating continual constriction of the stomach lining, restricting the production of the mucous barrier which protects the stomach, and allowing it to be attacked by the stomach acids. Similarly, depression can cause low serotonin in the body, which results in physical symptoms of extreme fatigue, sleep problems, and other physical disturbances which usually require medical intervention.
Research in Japan found that participants categorized as having high stress levels were more than twice as likely to die of heart disease or stroke as their counterparts in the low stress categories. Highly stressed individuals were also found to be more susceptible to diabetes, high blood pressure and problems with abnormal blood clotting.
Emotional anxiety contributes to a wide range of disorders, including asthma, cancer, hay fever, backache, migraine, heart disease, depression, fatigue, hypochondria, insomnia, loss of appetite, and the list goes on. In the case of somatogenic diseases discussed above, the emotional strain allows the body to more susceptible to the cause of illness.
Psychogenic diseases are those which are not caused by any invasion of bacteria or viruses. The mind is so powerful that it literally changes the physiology of the body to the point that one of it's processes breaks down or fails. You may know someone who was said to have died of a broken heart, and this is a good example of when the emotional trauma is so great that the other functions of the body are disrupted, causing heart failure or a similar premature end to life.
Children and those who are unable or unwilling to seek help for an emotional problem often begin to display physical symptoms. Eating disorders, sleep problems, frequently recurring and unexplained bouts of general sickness are often found to be rooted in emotional causes, and when the person is not able to effectively handle the underlying emotions, the problem is expressed in the form of physical illness. Similarly in adults who are unused to admitting that they may be suffering from an emotional stress, that individual may find himself frequently attending the doctors surgery with general aches and pains, suspected infections, concerns about failing eyesight or hearing, and sleeping problems. In severe cases this can lead to hypochondria, the condition of being overly obsessed with minor symptoms, believing everything to be indicative of a serious illness, and requiring constant assurance from medical professionals that they are not seriously unwell.
Some of the most recent research in the area has found that people suffering from depression are at greater risk of obesity and related health problems. As well as causing illness, stress is widely known to be a factor in delaying recovery from illness. Counseling and therapy are widely offered to help critically ill patients deal with the anxiety they suffer, as their doctors know that that very anxiety weakens the body's ability to heal.
There is compelling evidence both scientific and anecdotal that our emotions have a powerful impact on our physical well being. It is clear that a healthy body cannot exist independently from a healthy mind. This link reminds all of us of the importance of taking care of our emotional and psychological well being with as much dedication as we give to looking after our physical body.