Since the waste matter from all foods finally reaches the rectum, and since constipation is merely a difficulty in the forces of expulsion, it is hard to see how any normal food in the quantities usually eaten could have the slightest effect on the problem. When we remember that it takes food from twelve to twenty-four hours to reach the rectum, and that it has during all that time been subjected to the action of the powerful chemicals of the digestive tract, it is hard to imagine a piece of cheese, of whatever variety, strong enough to stop the contraction of the muscles of the upper rectum or to tie the sphincter-muscle into a knot. It would be difficult to find a food which could pass without effect through twenty-seven feet of intestinal tubing only to become suddenly effective on the wall of the rectum. If the wrong kind of food is the cause of constipation, why does the rectum prove to be the most refractory portion of the tube? On what principle could a piece of chocolate inhibit the call to stool or contract the sphincter muscle? On the other hand, even if it should be conceded that constipation were the result of lack of lubricating secretions in the colon, how could two tablespoonfuls of mineral oil be a sufficient lubricant after being mixed with liquid and solid food through many feet of the intestinal tract?
=An Adaptable Apparatus.= The lining of the intestines has plenty of secretions to take care of its function. It is as well adapted to the vicissitudes of life as are the other parts of the body. The muscular coat is no more liable to paralysis or spasm than are the voluntary muscles. As the skin adapts itself to all waters and all weathers, and as the lungs adjust themselves to varying air-pressures, so the intestinal wall makes ready adaptation to any common-sense demands, adjusting itself with ease to an athletic or a sedentary life, and to the normal variations of diet. What man has eaten throughout the centuries man may eat to-day. If you will but believe it, your intestines will make no more objection to white bread, blackberries, and cheese, along with all other ordinary articles of food, than the skin makes to varying kinds of water. Naturally, the suggested idea that a food will constipate tends to carry itself out to fulfilment and to prevent the call to stool from rising to the level of consciousness; but the real force lies not in the food but in the suggestion.
=The Bran Fad.= It is when we try to improve on the normal human diet that we really insult the body. He who leaves off eating nourishing white bread and takes to bran muffins is simply cheating his body. Bran has a small food value, but the human body is not made to extract it. Not only does bran fail to give us any nourishment itself, but it lessens the power of the intestines to care for other food. The fad for bran is based on the well-known fact that we need a certain quantity of bulk in order to stimulate the intestinal wall to normal peristalsis. We do need bulk, but not more than we naturally get from a normal and varied diet including a reasonable amount of fruit and vegetables.