A COMPARISON OF THE METABOLIC EFFECTS OF ISOCALORIC MEALS OF VARYING COMPOSITION, WITH SPECIAL REFERENCE TO THE PREVENTION OF POSTPRANDIAL HYPOGLYCEMIC SYMPTOMS

Abstract

Insufficient attention has been given to the fact that the typical American breakfast, relatively high in carbohydrate and low in protein and fat, predisposes to midmorning hypoglycemic symptoms and definite impairment in performance. Studies were undertaken to determine the changes in blood sugar level, caloric distribution, and metabolic rate following the ingestion of isocaloric breakfasts composed of varying proportions of carbohydrate, fat, and protein. A breakfast high in carbohydrate and low in protein and fat was followed by hypoglycemic symptoms in 1-2 hrs.; an isocaloric breakfast high in fat and low in carbohydrate and protein was followed by hypoglycemic S3''mptoms at a later hour; an isocaloric breakfast high in protein and low in fat and carbohydrate was followed by an improved sense of well-being and no symptoms of hypoglycemia. The blood sugar levels following these three breakfasts corresponded closely to the clinical symptoms. A sustained increase in metabolic rate occurred following the ingestion of the high protein breakfast, a transient increase followed by a fall below the basal rate was observed after the ingestion of an isocaloric high carbohydrate breakfast; no significant increase followed the ingestion of an isocaloric high fat breakfast. Following the ingestion of the high carbohydrate breakfast, differential derivation of calories reflected striking fluctuations in the character of the food substances utilized as sources of energy. These fluctuations did not occur following the isocaloric high protein and high fat meals.