Differential glycaemic effects of potato, rice and spaghetti in type 1 (insulin-dependent) diabetic patients at constant insulinaemia.

The blood glucose responses to cooked potato, rice and spaghetti were studied in six Type 1 (insulin-dependent) diabetic patients who had attained euglycaemia by the artificial pancreas prior to the meal intake. The amount of potato (raw weight 200 g), parboiled rice (raw weight 50 g), and spaghetti (raw weight 50 g) had approximately identical caloric content (range 203-225 kcal) and amount of available carbohydrate (range 39.4-43.4 g). The postprandial blood glucose response areas after cooked potato and cooked parboiled rice were similar (180 min values: cooked potato: 1190 +/- 110 mmol/l X min, cooked rice: 1160 +/- 140 mmol/l X min and 240 min values: cooked potato: 1690 +/- 140 mmol/l X min, cooked rice: 1740 +/- 210 mmol/l X min). In contrast, the response after cooked spaghetti was slower and less pronounced (180 min value: 830 +/- 80 mmol/l X min and 240 min value: 1320 +/- 120 mmol/l X min), and was significantly smaller than those of cooked potato (180 min: 2p less than 0.01 and 240 min: 2p less than 0.01) as well as cooked rice (180 min: 2p less than 0.01 and 240 min: 2p less than 0.02). Our study emphasizes the importance of determining the glycaemic response of foodstuffs under conditions of isoinsulinaemia.