Older work in man with meals of carbohydrates in water has indicated that such meals slow gastric emptying in proportion to their osomolarities. Nevertheless, different carbohydrates have been found to have differing efficacies per milliosmole. One possibility which would explain such discrepancies among carbohydrates is that hyperglycemia induced by carbohydrate absorption itself contributes to the slowing of gastric emptying. To test this possibility, normal subjects were made acutely hyperglycemic with intravenous loads of glucose during the ingestion of various liquid test meals, and rates of gastric emptying of these meals were compared in the same subjects during periods of induced hyperglycemia with rates of gastric emptying under euglycemia conditions. Induced hyperglycemia significantly slowed the rate of emptying of meals containing fat + protein, or protein, but did not significantly alter emptying of meals containing only NaCl. It is concluded that hyperglycemia does exert some effect on gastric emptying, but that these effects of hyperglycemia are variably expressed, depending on the presence of other factors which themselves slow gastric emptying.