People on low-calorie diets often go for ten days or mere...

People on low-calorie diets often go for ten days or mere with little or no difference on the scales, because their body had retained water. But on a total fast, the water-retaining mechanism apparently does not work, and the faster sees his improvement registered on the scales immediately. Loss of a pound and a half to two pounds a day at first is usual. This exceeds what would be expected on the basis of caloric expenditure.

Added to this gratifying visualization of fat literally pouring off by the pound is the fact that it is coming off without causing most of the patients hunger pangs. One man said, "After that first period ----- which for most people lasts only a day — you are all right." Said another, "When you are fasting, you are a little like a bear hibernating. You can talk and walk about, but you generally spend most of the time resting." (Without food you tire easily.) Why don't you get hungry? Dr.

Duncan discovered the answer to this question, and thereby made a significant contribution to the study of weight: hunger is lessened by the production of ketones, a kind of mild acidosis, in the faster's blood-stream. Blood -serum tests of patients showed that for the first 24 to 48 hours there was no significant ketone level ---- and the faster was hungry. When the tests showed an elevation in the ketone concentration in the blood, the food craving diminished.

The doctor can tell whether a person has broken, his fast simply by taking a blood-serum test for the ketones. Many people wished to stay on the fast even after 14 days, but Dr. Duncan wanted to be sure there were no unexpected ill-effects. He sent them home on 900 to 1,500 calorie diets which usually exceeded their desire for food for several days. They did not continue to lose weight, however; in fact, many gained a little. As appetites increased, the calorie intake increased as well.

This gain, Dr. Duncan and his associates found, could be corrected, by one or two-day fasts at appropriate intervals at the patient's home. Fasting for other than weight reduction purposes is a time-honoured practice. The Old and New Testaments mention it 74 times. Christ fasted 40 days and 4-0 nights. In Islam there is the universally observed 30-day, sunup-to-sundown fast of Ramadhan, and Buddhists find fasting appropriate to their way of contemplation and asceticism.