Friends, we have all heard the old saying ” a healthy mind in a healthy body”. Is this really true? Does our mental health affect our physical health? What is the relationship between the brain and the body… the nervous system and the immune system? Today in VERITAS,we explore this relationship. There are two response systems in our bodies: the Brain’s stress response system and the immune system. The stress response system creates/controls stress resulting from stimulus which occurs both within and outside the body. The immune system kills any external organisms and protects us from disease.
The internal steady state of a body is called homeostasis. This is the state of internal well being. The stress response system and the immune system try to maintain this state. The immune system and the nervous system communicate with each other. One hormone shared by the nervous system and the immune system is the corticotropin-releasing harmone(CRH). This hormone is produced in the brain. When released
the CRH causes the pituitary to release cortisol, the best known stress harmone. Now you must remember that the immune system is an
extremely lethal system and must be controlled. If it is not controlled it can go against the body it protects. The stress harmone cortisol controls the immune system. Also cortisol prevents the release of more CRH by the brain and thus regulates the immune system as well as the stress levels. Another important link between the nervous system and the immune system are the cytokines. The cytokines are protein molecules that send signals from the body’s immune system to the brain. This communication may be by directly going to the brain or by interacting with nerves as far away as the heart. A typical communication takes milliseconds. Activation of the brain by the cyclokines activates different stress responses
in the brain. The response is aimed at staying away from trouble as long as the body is ill. This is the reason why illness causes us to feel over sleepy or lazy. The body wants to get better before fighting again. The immune system tells the brain that the body is ill and should take care.
Of course what I have outlined above is just a small part of the vast communication that exists between the brain and the immune system. But what is clear is that stress and immunity are related. Stress is the brain’s way of controlling/reducing the effects of the immune system. The immune system and the stress response system control each other from overreacting to things.So what happens when you get stressed because of work/society? The brain does not know if this stress is caused by illness or by something else. Short term stress is okay but if you are stressed about something for a long term then the brain thinks ” this guy is ill. I am sure the Immune system is going overboard… so lemme control it”. It sends CRH and reduces the immune system. So your immunity is lowered
even though you were stressed because of your “cranky” boss. And you get ill. So stress reduces the immunity of the body. However very high levels of stress can sometimes increase the immune system for a short time. For example during exams students do not generally fall ill. But soon after exams when the pressure is off the illness occurs. However we must remember that different bodies have different stress thresholds and may react differently. There are several illnesses that can be caused by the break of interaction between the immune system and the nervous system. To give you an example : melancholia is a disease in which the immune system has forgotten to switch off the brain’s stress response system…. the result?
Very little sleep, not a good sense of humour, an over stressed individual. Take another example: depression is the result of hyperactive immune system. The stress response of the brain is lessened. The person sleeps too much, eats too much and gains weight. studies have shown that people with prolonged stress are more likely to have common cold. Interesting fact: About 20 % of patients with arthritis show clinical depression. You would think that the depression is because of their severe pain in the joints. But that is not the case! Sometimes the pain in the joints does not coincide with the depression symptoms. The reason for this is this: a disturbance in the body’s internal well being may sometimes manifest in the physical disorder(pain in joints) and sometimes in the mental disorder(depression) and sometimes in both. So if you have to remain healthy you have to take care of both your brain and your immune system.
So any problem inside the body may manifest itself as a physical disease or a mental disease. Today there is a lot of research going on to see if medicines for the nervous system can be used to cure diseases of the body and if antibiotics can be used to cure mental disorders by influencing the immune system. kanwar ( The information for this VERITAS has been taken
mainly from the Scientific American article ” The mind
body interaction in disease” by Sternberg and Gold. Thanks
to Sakharwade for sharing this article with me. ======================================
Go, wondrous creature! mount where Science guides:
Go, measure earth, weigh air, and state the tides:
Instruct the planets in what orbs to run,
Correct old time and regulate the Sun;