American Journal of Clinical Nutrition, Vol 25, 41-52, Copyright © 1972 by The American Society for Clinical Nutrition, Inc.

Effect of fasting, caloric restriction, and refeeding on glucose tolerance of normal men

¹ From the Metabolic Division, U.S. Army Medical Research and Nutrition Laboratory, Fitzsimons General Hospital, Denver, Colorado 80240

Alterations in the glucose tolerance test (GTT) and mineral balance of healthy, nonobese subjects were studied during periods of fasting, during refeeding, and while on a 500-kcal diet. Fasting for 48 hr produced an abnormal GTT that progressed in severity as fasts were prolonged to 72 and 96 hr. During fasting, a significant diurnal variation was observed for plasma free fatty acids and phosphate but not for plasma glucose, sodium, potassium, calcium, or chloride.

During refeeding over a 6-day period, the GTT was significantly abnormal on day 1 but not on day 2 or 3. On days 4 to 6, a significant deterioration in the GTT was observed for each of the subjects studied. During the 5th day of refeeding a significant natriuresis developed, which was accompanied by a significant increase in urine volume and reduction in water intake. Thus, the deterioration of the GTT during refeeding occurred concomitantly with a marked alteration in body fluid and electrolyte balance.

Our studies demonstrate that a 500-kcal diet containing 85 g sucrose/day maintains a normal GTT in normal subjects over a 10-day period of study. Other studies indicate, however, that a low carbohydrate diet may lead to deterioration of the GTT in patients with alterations of carbohydrate homeostasis.

This article has been cited by other articles:

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