FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

GOOSE BUMPS NOTHING TO BE FRIGHTENED OF

Question: I've often wondered why people shiver and get goose bumps in cold weather. I've also noticed that I get goose bumps when I'm frightened. What causes these things and what purpose do they serve?

Answer: The human body has a marvelously complex way of responding and adapting to changes in our environment. One of these interesting adaptive responses is the "goose bump" reaction that you mention. As you indicated, this reaction can be stimulated by cold temperature or a perceived threat.

The way our bodies respond to a stimulus like cold weather, fingernails squeaking along a blackboard or a scary movie invokes a complicated interaction between every system of the body. This involves the muscles, the heart and the nervous system - including the senses of sight, hearing, taste, touch and smell.

In cold weather exposure, the body tries to maintain the optimum internal temperature so that our vital organs can continue to function properly. The initial response is to shift the flow of blood to vital organs and away from the body parts that are not essential for life - the fingers and toes. This is why your fingers get cold quickly.

The goose bump reaction follows quickly after the redistribution of blood flow. Goose bumps are caused by the automatically controlled contraction of very tiny muscles within the skin named the erector pilorum muscles. They cause the hairs to "stand up" and become a better insulating coat. Since we humans have a rather sparse coating of fur, all we see is the goose bump effect of the contracted muscles. My cats, on the other hand, seem to double in size when they raise up their fur in an attempt to keep warm or to look more ferocious to a visiting feline.

You mentioned that you shiver as well as get goose bumps when you are cold. Shivering is another of the interesting complex and automatic responses our bodies make. It is the rapid contraction and relaxation of muscles done to increase the amount of body heat. Fortunately, the combination of these methods works very well. In the winter it isn't unusual for me to become chilled and develop goose bumps along with shivering, and then become warm. This is part of the joys of winter in Ohio! However, you can be in a sufficiently cold environment that the body, even with these adaptive measures, isn't able to keep you warm. If you get cold, then have goose bumps and shivering, and the shivering stops but you are still cold - you are in potentially big trouble. Get inside to a warm place before you get frostbite or an even more serious cold-related injury.

Question: I catch cold more often in the winter. Why?

Answer: A cold is that common affliction from which we have all suffered. The cold's symptoms of running nose, cough, sore throat, and body aches are caused by infection from one of the more than 100 members of the rhinovirus family.

The cold virus is amazingly contagious. In other words, all it takes is a gentle cough or sneeze from your infected co-worker, family member or passer-by to spread the virus to everyone within 20 feet. It is actually amazing that all of us don't have colds more often than we do. Fortunately, our bodies' defense mechanisms are adept at fighting off the invading cold virus. The reason for this is that our ancestors who weren't able to fend off the attacking cold virus died from it. Therefore, we have been genetically selected by our environment to be able to deal with rhinovirus infections.

During the cold weather months we have two factors that contribute to increased frequency of colds. First, we all tend to spend more time huddled together indoors where it is warm. This increases the opportunity to catch a cold. Second, the dryness of indoor winter air and the irritation it causes to the lining of the nose, throat and lungs makes it easier for the cold virus to invade the body.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.