Beads

For many years physicians have been interested in the rate of progress of food residues in their passage through the body. In making tests, patients have been required to swallow insoluble matter, such as small pieces of metal and charcoal or dye substances, which could be easily detected in the excretion. When the X-ray was discovered, barium sulphate, which is opaque to the Xray, was given, and the passage of the barium was observed through the fluoroscope. The giving of a large amount of indigestible material like barium with a small amount of milk or gruel, however, brings about conditions within the bowels which are hardly similar to the normal passage of food.

Twenty years ago, two English physiologists studied the distribution of food along the digestive tract by giving to rabbits large numbers of small glass beads. Then the rabbits were killed at various intervals, and the distribution of the material throughout the stomach and intestines was noted. Recently, Doctors Walter C. Alvarez and B. L. Freedlander, San Francisco, of the George Williams Hooper Foundation for Medical Research in the University of California Medical School, used a similar method in studying passage of food through the human body. They found that the normal individual with good digestion and a daily excretion does not in 24 hours pass anything like 100% of the material given. Fifty small beads were placed in a gelatin capsule and swallowed. These colored beads were given on three consecutive days; and the excretions were sieved so as to determine when the beads, and how many of them, were recovered. The beads used were very small, about two millimetres in diameter. Two of the individuals studied passed around 85% of the beads in 24 hours; but most took four days to get rid of 75%; and there were some who passed from only 50 to 60% in nine days. On an average, 15% of the beads were passed at the end of the first day; 40% on the second; 15% on the third; and from 5 to 10% on the fourth and fifth --so that between 90 and 100% come through by the end of the week. In one person who suffered with chronic constipation, careful sieving until all of the beads were accounted for showed that the last one came through on the 40th day. Since the beads had been mixed with the food, it is obvious that the individual's food residues also must have required this amount of time for passage.

The conclusions from this work are that wide variations in the rate of passage of food through the body are perfectly compatible with good health. All of the persons tested seemed to be normal on examination; and none of them admitted having poor digestion or poor health. Nevertheless, the rate of the movement of food varied greatly from very slow to very fast in the group of persons studied. The studies seemed to show also that the giving of purgative drugs, or that spontaneous, repeated emptying of the bowels results in such thorough emptying that no further excretions should be expected the next day, or even for one or two days following. The California physiologists also believe that there is little fear in general of the condition formerly called "autointoxication."