Glycaemic responses to different types of bread in insulin-dependent diabetic subjects (IDDM): studies at constant insulinaemia

To study the glycaemic effect of various Danish bread types in insulin-dependent diabetic subjects (IDDM) we looked at the incremental blood glucose areas after isocaloric meals of grained wholemeal rye bread, wholemeal bread (graham bread) and white bread in seven C-peptide negative diabetic subjects. Furthermore, we evaluated the glycaemic potency of dried fruits by exchanging 40 per cent of the starch of grained wholemeal rye bread as dried figs. Prior to the meal intake the patients had attained normoglycaemia and isoinsulinaemia by means of the artificial pancreas. The four test meals containing 50 g of available carbohydrate were taken in random order. The postprandial blood glucose response areas after whole-meal bread (1037 +/- 113 mM X 180 min) and white bread (1021 +/- 100 mM X 180 min) were significantly higher than that to grained wholemeal rye bread (786 +/- 66 mM X 180 min, P less than 0.05). Exchange of 40 per cent of the complex carbohydrate as grained wholemeal rye bread with simple sugars, such as figs, had no influence on the blood glucose response (786 +/- 66 mM X 180 min vs. 766 +/- 56 mM X 180 min). Constant and identical serum-free insulin levels at 30 mU/l and similar amounts of glucose lost in the urine were found after the four test meals. In conclusion, the difference in extraction rate of wheat in the form of white flour (0, 7) and wholemeal flour (1, 0) was not reflected in the glycaemic responses in IDDM subjects. Grained wholemeal rye bread is a fibre-rich, cheap nutrient which elicits a significantly lower glycaemic response compared to wholemeal and white bread and can be recommended to diabetic subjects.     

Influence of the amount of starch on the glycaemic index to rice in non-insulin-dependent diabetic subjects.

To test whether the glycaemic index is altered by the amount of carbohydrate, meals containing 25 and 50 g carbohydrate as white rice and white bread were taken by seven non-insulin-dependent diabetic subjects. The glycaemic indices to parboiled white rice corresponding to 25 and 50 g carbohydrate were similar, being 55 (SE 10) and 60 (SE 8) respectively. The incremental areas of blood glucose (above basal) to parboiled white rice were significantly lower than to white bread after both an amount corresponding to 25 g carbohydrate (85 (SE 24) mM x 180 min v. 181 (SE 55) mM x 180 min; P less than 0.01) and to 50 g carbohydrate 226 (SE 29) mM x 180 min v. 423 (SE 76) mM x 180 min; P less than 0.01). Similar insulin response areas to 25 g carbohydrate given as parboiled white rice and white bread were found, whereas 50 g carbohydrate as white bread caused a significantly higher insulin response area than parboiled white rice (P less than 0.05). In conclusion, the glycaemic index of parboiled white rice is not affected by the amount of carbohydrate ingested, at least under the present study conditions.     

Water volume and consumption time: influence on the glycemic and insulinemic responses in non-insulin-dependent diabetic subjects

The present study was carried out to see if either the volume of water or the duration of ingestion time influence the postprandial blood glucose and insulin responses in non-insulin-dependent diabetic (NIDDM) subjects. Small test meals containing 40 g carbohydrate as rye bread (100 g) with butter (10 g) and tomatoes (75 g) were given to 10 NIDDM subjects. The meals were taken in random order with either 90 or 600 mL tap water. The meal with 90 mL tap water was ingested over 10 and 30 min. The glycemic responses to isocaloric meals of large and small volumes were similar (338 +/- 56 vs 384 +/- 67 mmol/L.240 min) as were the insulinemic responses (29,424 +/- 6512 min vs 27,140 +/- 6548 mumol/L.240 min). An extension of eating time from 10 to 30 min did not alter the glycemic (384 +/- 67 vs 370 +/- 54 mmol/L.240 min) or the insulinemic response (27,140 +/- 6548 vs 35,670 +/- 10,245 mumol/L.240 min) in the NIDDM patients.     

Glycaemic and insulinaemic responses to orange and apple compared with white bread in non-insulin-dependent diabetic subjects.

To study the postprandial blood glucose and insulin responses to exchangeable amounts of simple and complex carbohydrates, eight non-insulin-dependent diabetic subjects consumed 227 g apple, 280 g orange or 50 g white bread on three separate days. The mean postprandial blood glucose response area to white bread (404 +/- 95 mM x 240 min) was significantly higher compared with orange (131 +/- 34 mM x 240 min; P less than 0.05) and apple (157 +/- 57 mM x 240 min; P less than 0.05). Thr glycaemic indices of the fruits were identical: 44 +/- 13 (orange) and 40 +/- 11 (apple). The low glycaemic response to orange and apple may be ascribed to the high content of fructose which is rapidly cleared and metabolized by the liver, without elevating the blood glucose.     

The impact of freezing and toasting on the glycaemic response of white bread

OBJECTIVE: To investigate the impact of freezing and toasting on the glycaemic response of white bread. SUBJECTS/METHODS: Ten healthy subjects (three male, seven female), aged 22-59 years, recruited from Oxford Brookes University and the local community. A homemade white bread and a commercial white bread were administered following four different storage and preparation conditions: (1) fresh; (2) frozen and defrosted; (3) toasted; (4) toasted following freezing and defrosting. They were administered randomized repeated measures design. Incremental blood glucose, peak glucose response, 2 h incremental area under the glucose response curve (IAUC). RESULTS: The different storage and preparation conditions resulted in lower blood glucose IAUC values compared to both types of fresh white bread. In particular, compared to the fresh homemade bread (IAUC 259 mmol min/l), IAUC was significantly lower when the bread was frozen and defrosted (179 mmol min/l, P<0.05), toasted (193 mmol min/l, P<0.01) and toasted following freezing and defrosting (157 mmol min/l, P<0.01). Similarly, compared to the fresh commercial white bread (253 mmol min/l), IAUC was significantly lower when the bread was toasted (183 mmol min/l, P<0.01) and frozen, defrosted and toasted (187 mmol min/l, P<0.01). CONCLUSIONS: All three procedures investigated, freezing and defrosting, toasting from fresh, and toasting following freezing and defrosting, favourably altered the glucose response of the breads. This is the first study known to the authors to show reductions in glycaemic response as a result of changes in storage conditions and the preparation of white bread before consumption. In addition, the study highlights a need to define and maintain storage conditions of white bread if used as a reference food in the determination of the glycaemic index of foods.     

Breakfast glycaemic response in patients with type 2 diabetes: effects of bedtime dietary carbohydrates.

OBJECTIVES: Bedtime carbohydrate (CHO) intake in patients with type-2 diabetes may improve glucose tolerance at breakfast the next morning. We examined the 'overnight second-meal effect' of bedtime supplements containing 'rapid' or 'slow' CHOs. DESIGN: Randomized cross-over study with three test-periods, each consisting of two days on a standardized diet, followed by a breakfast tolerance test on the third morning. SETTING: The Lundberg Laboratory for Diabetes Research, Sahlgrenska University Hospital, G?teborg, Sweden. SUBJECTS: Sixteen patients with type 2 diabetes on oral agents and/or diet. INTERVENTIONS: Two different bedtime (22.00 h) CHO supplements (0.46 g available CHO/kg body weight) were compared to a starch-free placebo ('normal' food regimen). The CHOs were provided as uncooked cornstarch (slow-release CHOs) or white bread (rapid CHOs). RESULTS: On the mornings after different bedtime meals we found similar fasting glucose, insulin, free fatty acid and lactate levels. However, the glycaemic response after breakfast was 21% less after uncooked cornstarch compared to placebo ingestion at bedtime (406 +/- 46 vs 511 +/- 61 mmol min l(-1), P < 0.01). In contrast, it did not differ when the evening meal consisted of white bread (451 +/- 57 mmol min l(-1)) compared to placebo. According to an in vitro analysis, uncooked cornstarch contained approximately 4 times more slowly digestible starch as compared to white bread. CONCLUSIONS: A bedtime meal providing uncooked cornstarch improved breakfast tolerance the next morning while, in contrast, this was not found following a bedtime meal of white bread. The results are consistent, therefore, with the concept that an increased intake of slowly digestible carbohydrates exert an overnight second-meal effect in patients with type 2 diabetes.     

Comparison of the effects of dried peas with those of potatoes in mixed meals on postprandial glucose and insulin concentrations in patients with type 2 diabetes

BACKGROUND: Data on the blood glucose response of diabetic patients to mixed meals containing food both rich in fiber and with a low glycemic index, such as dried peas, is scarce. Thus, the extent to which type 2 diabetic patients should take into account low-glycemic, high-fiber foods for their daily carbohydrate intake is uncertain. OBJECTIVE: We compared the glycemic and insulinemic responses to 3 different meals based on dried peas, potatoes, or both in patients with type 2 diabetes undergoing dietary treatment. DESIGN: The meals, prepared according to local recipes and consumed at weekly intervals in random order at lunchtime, contained comparable amounts of carbohydrate, fat, protein, and water. The carbohydrate source of the meals differed and was supplied from either dried peas (meal 1), potatoes (meal 3), or a combination thereof (meal 2). Peripheral and venous blood was sampled over 180 min. RESULTS: The increases in postprandial plasma glucose and insulin concentrations were delayed and significantly smaller after the pea meal than after the potato meal. The areas under the glucose curve were 164 +/- 40, 257 +/- 57, and 381 +/- 40 mmol x 180 min/L for meals 1, 2, and 3, respectively (P < 0.01). The areas under the insulin curve were 13.8 +/- 4.3, 15.4 +/- 3.9, and 31.2 +/- 6.9 nmol x 180 min/L, respectively (P = 0.0514). CONCLUSION: These findings suggest that carbohydrates in dried peas may be largely disregarded in carbohydrate counting and that type 2 diabetic patients should probably increase their consumption of low-glycemic, high-fiber foods at the expense of high-glycemic, low-fiber foods.     

Prediction of glycemic response to mixed meals in noninsulin-dependent diabetic subjects

Recent studies suggest the glycemic response of different mixed meals cannot be predicted from the glycemic index (GI) of individual carbohydrate foods. Postprandial glucose levels following five different mixed meals in six noninsulin-dependent diabetic volunteers were therefore assessed. Each meal comprised 50% carbohydrate, 30% fat, and 20% protein, varying only in type of carbohydrate. The carbohydrate exchanged in each meal (potato, white bread, rice, spaghetti, or lentils and barley) contributed 37% of total meal calories. The correlation between predicted glucose response and postprandial glucose area was highly significant; estimated meal GI was virtually proportional to the actual mean glycemic response. These results demonstrate that the relative glycemic effects of mixed meals can be predicted from the GI of their carbohydrate components, again stressing the importance of type of carbohydrate in regulating postprandial blood-glucose levels.     

Glycaemic and metabolic responses to a traditional cereal–-legume mixture

The study was conducted to evaluate the acute postprandial and long-term metabolic response to a traditional mixture of barley (Hordeum vulgare), Bengal gram (Cicer arietinum) and wheat (Triticum aestivum). The acute study was performed on eight healthy subjects (five male, three female) and six subjects with non-insulin dependent diabetes mellitus (NIDDM) (four male, two female). Each subject underwent two 50g carbohydrate meal tolerance tests (MTT), one with white bread (reference meal) and another with chapaties made from the cereal-pulse mixture (CP). The postprandial glycaemic and insulinaemic responses to CP were attenuated compared to those to white bread, the glycaemic index being 68.6 and 64.9 in healthy and NIDDM subjects, respectively, and the insulinaemic index being 88.1 and 66.0 in healthy and NIDDM subjects, respectively.     

Bioavailability of starch in bread rich in amylose: metabolic responses in healthy subjects and starch structure.

OBJECTIVE: This study investigated whether postprandial metabolic responses to bread could be lowered by substituting high amylose maize starch for a part of the flour. DESIGN AND SUBJECTS: Eight healthy subjects consumed test meals of equivalent nutritional composition based on white wheat bread, bread rich in amylose (HAWB) and spaghetti as a breakfast meal. Blood samples were collected to measure insulin and glucose concentration during two hours after consumption. The degree of starch crystallinity was investigated by X-ray diffraction and DSC analysis. RESULTS: HAWB produced low glycaemic (60 +/- 18) and insulinaemic (57 +/- 20) indexes similar to those of spaghetti (83 +/- 46, 61 +/- 16). In vitro amylase hydrolysis of the three foods showed that high amylose content in HAWB significantly lowered starch degradation in bread without affecting hydrolysis kinetics. Addition of amylose in dough increased the resistant starch content of HAWB (14% of dry matter). The resistant starch fraction was mainly composed of crystalline amylose (B-type X-ray diffraction pattern, melting temperature 105 degrees C) attributable to native high amylose maize starch incompletely gelatinised during bread-cooking. CONCLUSIONS: Bread produced by the substitution of high amylose maize starch for a part of wheat flour showed a low glycaemic index. Resistant starch in HAWB corresponded to native crystalline amylose not gelatinised during normal bread-processing conditions.     

Differential effect of protein and fat ingestion on blood glucose responses to high- and low-glycemic-index carbohydrates in noninsulin-dependent diabetic subjects

Six noninsulin-dependent diabetic subjects received meals containing 25 g carbohydrate either as potato or as spaghetti. The meals were repeated with the addition of 25 g protein and with 25 g protein and 25 g fat. Blood glucose and insulin responses were measured for 4 h after the test meal. When carbohydrate was given alone, the blood glucose and serum insulin increments were higher for the potato meal. The addition of protein increased the insulin responses to both carbohydrates and slightly reduced the glycemic response to mashed potato (F = 2.04, p less than 0.05). The further addition of fat reduced the glycemic response to mashed potato (F = 14.63, p less than 0.001) without any change in the blood glucose response to spaghetti (F = 0.94, NS). The different responses to coingestion of protein and fat reduced the difference between the glycemic responses to the two carbohydrates.     

Insulin response and glycemic effects of meals in non-insulin-dependent diabetes

Glycemic and hormonal responses to two breakfast mixed meals were studied in six obese subjects with NIDDM. The study evaluated a high-glycemic-effect (HGE) and a low-glycemic-effect (LGE) meal, each with approximately 600 kcal and 12% protein, 15% fat, and 73% carbohydrate. Plasma insulin and counterregulatory hormones were measured at baseline and at 30-min intervals for 5 h after meals. Mean fasting plasma glucose and insulin concentrations were similar before both studies: for the LGE meal, 11.9 +/- 1.8 mmol/L and 261.9 +/- 50.1 pmol/L; for the HGE meal, 11.9 +/- 2.0 mmol/L and 262.6 +/- 43.1 pmol/L. Peak plasma glucose concentrations were approximately 25% lower with the LGE meal and the area under the glucose curve was 63% of that obtained for the HGE meal (p less than 0.05). Although the integrated insulin responses of the two meals did not differ, the peak occurred 60 min earlier in the LGE meal (p less than 0.05). The LGE meal may produce a lower glycemic response, in part because of earlier insulin secretion.     

Relationship of satiety to postprandial glycaemic, insulin and cholecystokinin responses.

The effect of plasma glucose on satiety and the capacity of carbohydrates to stimulate cholecystokinin (CCK) remain unclear. The aim of this study was to test the hypothesis that the magnitude of the postprandial plasma glucose and insulin response is inversely related to the CCK response and to subjective satiety. Seven healthy, male volunteers consumed equal carbohydrate portions (0.5 g/kg body weight) of six test meals (Rice Bubbles, Sustain, Vita-Brits, All-Bran, porridge and white bread) in random order after an overnight fast. An egg and bacon meal was consumed as a non-carbohydrate control providing 0.5 g protein/kg body weight. Serum CCK, plasma glucose and insulin and subjective satiety (measured by a rating scale) were assessed over 3 h and quantified using the glycaemic index (GI), insulin index (II), the peak satiety score and area under the incremental curve (AUC). The observed GIs (mean +/- SE) ranged from 42.5 +/- 2.6 for All-Bran to 116.2 +/- 11.4 for Rice Bubbles, using white bread as the reference food (GI = 100). Peak satiety scores varied eightfold from 0.21 +/- 0.4 for Sustain to 1.64 +/- 0.4 for All-Bran. Significant inverse relationships were observed between the peak satiety score and both the glycaemic and insulin index of the seven meals (r = -0.916, p less than 0.001 and r = -0.926, p less than 0.001). A direct relationship was observed between satiety (AUC) and the CCK response (AUC) (r = 0.73 p less than 0.01). The results suggest that glycaemic and insulin responses to carbohydrate foods are inversely proportional to the CCK response and satiety.     

Blood glucose and insulin responses to different meals in non-insulin-dependent diabetic subjects of both sexes.

The influence of sex on glucose and insulin responses in patients with non-insulin-dependent diabetes was studied in 12 men and 11 matched women. Two meals of either 100 g white bread or 60 g (raw weight) white rice were given. Blood glucose response areas to white bread (517 vs 509 mmol/L) and to rice (306 vs 353 mmol/L) over a 300-min observation period were similar in females and males, respectively. Insulin responses showed an identical pattern to that of glucose in females and males--35784 vs 28230 pmol/L after white bread and 28044 vs 19464 pmol/L min after rice (NS) over a 300-min observation period, respectively. Within the two study groups, blood glucose-response areas to white bread were significantly higher than those to rice (P less than 0.05), whereas there were no differences in insulin-response areas within or between the two groups. The glycemic index of rice for females (62 +/- 9; mean +/- SE) and males (66 +/- 5) was similar.     

Low glycemic response to traditionally processed wheat and rye products: bulgur and pumpernickel bread

To look at the effect of processing wheat and rye on blood glucose responses with special reference to bulgur and pumpernickel bread, groups of 9-12 Noninsulin-dependent (NIDDM) and 5-6 Insulin-dependent diabetic volunteers (IDDM) were fed test meals containing 50 g carbohydrate portions of four wheat and three rye products. Glycemic indices for IDDM and NIDDM combined, calculated as the incremental area under the blood glucose response curve, where white bread = 100, demonstrated values of 96 +/- 5 for wholemeal wheat bread, 89 +/- 6 for wholemeal rye bread, 78 +/- 3 for pumpernickel bread, 65 +/- 4 for bulgur, 63 +/- 6 for whole wheat kernels and 48 +/- 5 for whole rye kernels. Results for IDDM and NIDDM were similar (r = 0.96, p less than 0.01). It is concluded that traditional processing of cereals, such as parboiling (bulgur) or the use of wholegrains in bread (pumpernickel) may result in the low GI value associated with the unmilled cereal. Cereal foods processed in these ways may form a useful part of the diet where a reduction in postprandial glycemia is required.     

Relationship between the rate of gastric emptying and glucose and insulin responses to starchy foods in young healthy adults

Twelve young healthy adults (five men, seven women) ingested four test meals on four occasions so we could examine the relationship between the rate of gastric emptying (GE) and the glucose response to different starchy foods. Each meal consisted of one food product containing 50 g starch: spaghetti, rice, French bread, or mashed potato. Basal and postprandial glucose and insulin responses were measured for 3 h. The foods were labeled with 3.7 MBq Tc99m-albumin and GE was studied by scintigraphy for 3 h. The rate of GE (expressed by the GE half-time) was fastest for mashed potatoes, then bread, rice, and slowest for spaghetti. Blood glucose and serum insulin responses were similar. A significant negative correlation was found between the GE half-time and the maximum variation in blood glucose level (r = -0.6, p less than 0.0001). The glucose response to all four foods is strongly related to the GE rate.     

Influence of sterilization, drying and oat bran enrichment of pasta on glucose and insulin responses in healthy subjects and on the rate and extent of in vitro starch digestion.

The effects of sterilization and oat bran enrichment of pasta on the glucose and insulin responses in healthy subjects were evaluated. Cooked and canned spaghetti and cooked fettucini without and with enrichment with oat bran (28%) were compared. Further, the effects of various low- and high-temperature drying conditions for spaghetti, cooking time and sterilization on the starch digestion rate and content of enzyme-resistant starch (RS) in vitro were also studied. Various cooking quality data were also determined to allow interpretation of results. The incremental glucose area (0-120 min) produced by canned spaghetti was twice the area of that produced by cooked spaghetti (69.03 vs 35.45 mmol/l x min, P less than 0.01). The incremental insulin area (0-120 min) was also significantly higher with canned spaghetti (17,500 vs 12,600 pmol/l x min, P less than 0.05). The rapid digestion was caused by excessive swelling of starch during sterilization that promoted a very soft texture of the spaghetti. Enrichment of fettucini with oat bran reduced slightly the incremental insulin area (15,600 vs 20,100 pmol/l x min, P less than 0.05, for 0-120 min), but did not significantly reduce the glucose area. Drying conditions and cooking times could be varied within broad limits without affecting the rate of starch digestion in vitro of cooked spaghetti. In sterilized spaghetti the content of resistant starch was higher than that found in cooked 'al dente' spaghetti (2.2-3.4 vs 0.5 mg/100 mg total starch). In conclusion, sterilization influences the nutritional properties of starch in pasta by substantially increasing the glucose and insulin responses and by formation of resistant starch. The effect of oatbran environment is restricted mainly to a slight decrease in the insulin response.     

Effect of diet on glucose tolerance 36 hours after glycogen-depleting exercise.

In order to estimate the effect of muscle glycogen content on the glycaemic response, glucose tolerance and glucose oxidation were measured in eight healthy male subjects. Each subject followed three different treatments, consisting of either a physical exercise session followed by 36 h of a low-carbohydrate high-fat diet (glycogen depletion treatment); or a physical exercise followed by 36 h of a high carbohydrate diet (glycogen repletion treatment); or a low-carbohydrate high-fat diet alone (diet treatment). After both the glycogen depletion and the diet treatments, the subjects showed a high glycaemic response (443 +/- 57 and 419 +/- 63 mmol.min/l resp.), a high insulinaemic response (7158 +/- 671 and 7643 +/- 913 mU.min/l), and a low rate of glucose oxidation (27.5 +/- 2.4 and 31.0 +/- 5.8 g/3 h respiration). In contrast, after the glycogen repletion treatment, the subjects had a lower glycaemic response (197 +/- 21 mmol.min/l), a lower insulinaemic response (4645 +/- 327 mU.min/l) and a higher glucose oxidation level (47.4 +/- 2.0 g/3h). Fasting free fatty acids (FFA) were positively correlated with glucose area (P less than 0.001) and negatively with glucose oxidation (P less than 0.01). These results show a strong inhibitory effect of the low-carbohydrate high-fat diet on glucose tolerance despite prior strenuous exercise. Because of this, the effect of the muscle glycogen content could not be tested. However, the results suggest that the FFA/glucose interrelationship may override exercise-induced changes in insulin-stimulated glucose uptake.     

Glycaemic index of parboiled rice depends on the severity of processing: study in type 2 diabetic subjects

OBJECTIVE: To study the influence of parboiling and the severity of the process on glycaemic and insulinaemic responses to rice in type 2 diabetes. Moreover, to examine changes in starch structure related to parboiling, which may affect the metabolic responses and digestibility. DESIGN: Nine type 2 diabetic subjects ingested four test meals: white bread (WB) and three meals of cooked polished rice of the same variety being non-parboiled (NP), mildly traditionally parboiled (TP) and severely pressure parboiled (PP). The participants ingested the test meals (50 g available carbohydrates) on separate occasions after an overnight fast. SETTING: Outpatient clinic, Dept. Endocrinology and Metabolism, Aarhus University Hospital, Denmark. RESULTS: All three rice samples elicited lower postprandial plasma glucose response (NP: 335+/-43; TP: 274+/-53; PP: 231+/-37 mmol/1*180 min.; means+/-s.e.m.) than white bread (626+/-80; P<0.001), within rice samples PP tended to be lower than NP (P=0.07). The glycaemic indices were: NP: 55+/-5, TP: 46+/-8 and PP: 39+/-6, and lower for PP than NP (P<0.05). The insulin responses were similar for the three rice meals, which were all lower than that to white bread (P<0.001). Differential scanning calorimetry showed the presence of amylose-lipid complexes in all rice samples and of retrograded amylopectin in PP. Amylose retrogradation was not detected in any of the rice samples. CONCLUSIONS: All rice test meals were low-glycaemic in type 2 diabetic subjects. There was no effect of TP on glycaemic index, whereas PP reduced the glycaemic index by almost 30% compared to NP. Sponsorship: The Royal Veterinary and Agricultural University, Aarhus University Hospital, Danish International Development Assistance (DANIDA), Ministry of Foreign Affairs and the 'Konsul Johannes Fogh-Nielsens og Fru Ella Fogh-Nielsens Legat' foundation.     

Milk as a supplement to mixed meals may elevate postprandial insulinaemia

OBJECTIVE: The objective was to evaluate the impact of milk added to a high-glycaemic index (GI) white bread meal vs a low-GI spaghetti meal, respectively, on postprandial glucose and insulin responses in healthy subjects. DESIGN: The volunteers were served the bread or spaghetti meals with either milk (200 or 400 ml, respectively) or water (400 ml) following an overnight fast. Capillary blood samples were collected before and during 3 h after the meals. SETTING: The study was performed at the Department of Applied Nutrition and Food Chemistry, Lund University, Sweden. SUBJECTS: Ten healthy volunteers, seven men and three women, aged 22-30 y, with normal body mass indices, were recruited. RESULTS: There was no difference in postprandial glucose area under curve (AUC) with and without added milk in the case of the high-GI bread meals. As could be expected, glucose AUC after the bread meal+water was higher than after the spaghetti meal+water. Milk added at 200 or 400 ml to the spaghetti meal did not affect glucose AUC. However, a significantly higher insulin AUC was seen with the bread meal with 400 ml milk (+65%) and the spaghetti meal with 200 ml or 400 ml milk (+300%), respectively, compared with corresponding test meal with water CONCLUSIONS: The addition of milk to a low-GI spaghetti meal may significantly increase the postprandial insulinaemia. Even an ordinary amount of milk (200 ml) increased the insulin AUC to a low-GI spaghetti meal to the same level as seen with white bread. The mechanism for the insulinotrophic effect of milk is not known, and the potential long-term metabolic consequences need to be elucidated. SPONSORSHIP: Swedish Dairy Association.