No. 45: May-Jun 1986
Hints are accumulating from many clinical studies that one's mental state has much to do with the effectiveness of one's immunological system. Happy, unstressed people get fewer colds. Introverts get worse colds than extroverts. Men who have just lost their wives have lowered white-cell responses. Although many physicians and medical researchers think it too early to claim that mental stress significantly suppresses the human immunological system and thus leads to more illness, one can see the pendulum start to swing away from the timehonored belief that mind and body are entirely separate entities.
The foregoing studies and others like them are discussed in a recent survey of psychoimmunology by B. Dixon. Toward the close of the article, Dixon asks why humans (and other animals, too) have evolved an immunological system sensitive to stress. Evolutionists can always find some sort of justification in Darwinian terms, and Dixon's is rather ingenious. Suppose a primitive human was attacked by a saber-toothed tiger (what else?). If the human survived, his immunological system would immediately go into high gear to clean up the wounds and repel invading germs. The trouble is that a revved-up immunological system (especially the white blood cells) can go too far and chomp up healthy tissue, too. However, evolution has constructed animals such that stress (saber-toothed tigers are stressful!) suppresses the immunological system to restrict the consumption of healthy tissues. While this short-term damper on immunological activity may have been useful to primitive humans, the stresses on modern man are less intense and long-term. We are sick a lot, particularly with cancer, because evolution has not yet adjusted or finetuned us to the new environment.
(Dixon, Bernard; "Dangerous Thoughts," Science 86, 7:63, April 1986.)