The respiratory exchange of a human in the post-absorptive condition was determined by two different methods, for from three to four hours after the ingestion of dextrose in amounts between 5 and 104 grams in water at 37° C. In the majority of the observations, the maximum respiratory quotient was observed in the third half hour, and all amounts of 10 grams or over were accompanied by significant changes in the respiratory quotient. Increases in the metabolism of carbohydrate were observed in the first one and one-half hours with amounts of 5 to 10 grams, in 3 hours with 15 grams and in three and one-half to four hours with 21 to 25 grams. The increase in carbohydrate metabolism above basal for 3 hours represented on the average from 17 to 31 per cent of the amount of dextrose ingested in quantities of 10 to 36 grams. The increase in heat production was practically 1 calorie for each additional 5 grams from 5 to 25 grams. The increase in the heat production above 25-gram amounts rose more rapidly in proportion to the additional amounts given. The specific dynamic action, that is, the relation of the increase in heat production to the energy value of the ingested dextrose, varied from 4 to 6 per cent when 5 to 36 grams were given. When 52 grams were taken, the value was 10 per cent.