High-fiber foods at breakfast: influence on plasma glucose and insulin responses to lunch

This study evaluates acute effects of red kidney bean consumption on postprandial glucose and insulin responses in six healthy young men. Comparisons were made among three mixed-food breakfast meals comprised predominantly of either red kidney beans, bran cereal, or white bread. These meals provided equivalent levels of digestible carbohydrate, protein, and fat. The bean and bran meals contained equivalent levels of fiber while the white-bread meal contained a lower level. The postprandial glucose and insulin responses to the three meals were similar and responses also were similar after a standard whole-wheat-bread meal 4 h later. There appeared to be a reciprocal relationship between glucose and insulin responses after the lunch meal. This would influence interpretation of data regarding second-meal response.     

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.     

Effect of the glycemic index and content of indigestible carbohydrates of cereal-based breakfast meals on glucose tolerance at lunch in healthy subjects

BACKGROUND: Diets with a low glycemic index (GI) have been shown to improve glucose tolerance in both healthy and diabetic subjects. Two potential mechanisms are discussed in relation to long-term metabolic effects: a decreased demand for insulin in the postprandial phase and formation of short-chain fatty acids from fermentation of indigestible carbohydrates in the colon. OBJECTIVE: The objective was to study the effect of the GI and the indigestible carbohydrate--resistant starch (RS) and dietary fiber (DF)--content of cereal-based breakfasts on glucose tolerance at a second meal (lunch) in healthy subjects. DESIGN: The effects of 7 test breakfasts with known GIs (GI: 52-99) and RS + DF contents (2-36 g) were evaluated. White-wheat bread was used as a reference breakfast (high GI, low RS + DF content). Glucose and insulin responses after the second meal were measured in healthy subjects. In addition, the satiating capacity of 4 of the 7 test breakfasts was estimated before and during the second meal. RESULTS: Two of the 4 low-GI breakfasts improved glucose tolerance at the second meal. Only these 2 breakfasts were capable of postponing the in-between-meal fasting state. There was no measurable effect of fermentable carbohydrates on glucose tolerance at the second meal. The highest satiety score was associated with the barley breakfast that had a low GI and a high RS + DF content. CONCLUSIONS: Glucose tolerance can improve in a single day. Slow absorption and digestion of starch from the breakfast meal, but not the content of indigestible carbohydrates in the breakfast meal, improved glucose tolerance at the second meal (lunch).     

Effect of redesigned Indian mixed meals on blood glucose and insulin levels in normal versus type 2 diabetic subjects--a comparative study

This study reports the glycemic as well as insulinemic response of seven types of Indian vegetarian mixed meals (MMs). Each of the seven MMs was given at weekly intervals to both normal and type 2 diabetic subjects on the same day to reduce variations in food preparations. In this Indian study, each MM consisted of five to six food items with a low glycemic index (GI) ranging from 28.98 to 46.12%, glycemic load ranging from 15.58 to 23.8 g and energy value (calculated) from each test meal ranging from 403 to 502 kcal. All the seven meals were found to have postprandial glycemic control in normal subjects which ranged from 86 to 102.4 mg%, and a good postprandial glycemic control in type 2 diabetic subjects which ranged from 132.8 to 148.4 mg%, and hence appropriate for routine consumption by diabetic subjects. The glycemic and insulinemic pattern of all these MMs was similar in normal and diabetic subjects. Sustained intake of such low GI MMs by diabetic can result in good glycemic control.     

Repeated consumption of high-fiber breakfasts: effects on postprandial glucose and insulin responses after breakfast and lunch

The objective of this study was to evaluate the effects of repeated consumption of two high-fiber diets on postprandial glucose and insulin responses. Two mixed-food breakfast meals composed predominantly of either red kidney beans or bran cereal were fed to six healthy young men. The meals provided equivalent levels of digestible carbohydrate, protein, fat, and fiber. Insulin responses measured after breakfast were lower with the bean diet than with the bran cereal diet but higher when measured after a standard lunch. No significant interactions were found between the diets and the length of the time the subjects were on the diets (days 1 vs 7). In comparison to the postprandial responses on day 1 of the diet periods, postprandial responses on day 7 showed reduced glucose and insulin responses to breakfast and reduced insulin responses to lunch. Responses to an oral glucose tolerance test were not affected by repeated consumption of these diets.     

食用西瓜对2型糖尿病患者血糖的影响

目的　探讨同等热能的馒头与西瓜的餐后血糖反应。方法　随机选取空腹血糖＜ １１ ．１ｍｍｏｌ／Ｌ 的２型糖尿病患者２５ 例，分别在间隔１ 周的两顿早餐仅给予热能相等的５０ 克馒头或６１１ 克去皮去籽西瓜作为试验餐，比较进食两种食物后的血糖情况。结果　西瓜的餐后血糖高峰时间（ 均在餐后半小时） 较多数馒头餐（２２ 例在餐后１ 或１ ．５ 小时，３ 例在餐后半小时） 明显提前，而两种食品的血糖高峰值与血糖曲线下面积无明显差异（Ｐ＞ ０．０５）。结论　非严重高血糖的２ 型糖尿病患者可吃少量西瓜，但必须扣除同等热能的粮食。     

Variability of blood glucose and plasma insulin responses after replacing ham by egg in the breakfast of obese subjects

The effects of replacing ham protein by egg protein was tested in eleven obese subjects during two isocaloric breakfasts. Blood glucose (BG) and plasma insulin (IRI) responses were measured during four hours. The replacement of ham by egg significantly decreased blood glucose levels in all subjects. However, the variability of the responses led us to divide the obese subjects into two subgroups. In five subjects (E group), the replacement of ham by egg produced a significant decrease in blood glucose and plasma insulin responses (BG: from 7.71±0.50 to 6.66±0.61 mmol/l at 30 minutes; IRI: from 148±23 to 76±12 μU/ml at 50 minutes). No effect was observed in the other six subjects (N.E. group) apart from an increase in BG from 6.55±0.50 to 7.55±0.55 mmol/l at 65 minutes. Among the known parameters of the study, the postprandial decrease in blood glucose levels observed after egg intake in some obese subjects seemed to be related, to the usual caloric intake of the subjects before the experiment. The usual caloric intake and the detailed composition of meals must therefore be given when metabolic studies on glucose tolerance are carried out in obese subjects.     

Plasma glucose and insulin responses to traditional Pima Indian meals

The in vivo glycemic and insulin responses and in vitro starch digestibility were determined for six staple foods (corn, lima beans, white and yellow teparies, mesquite, and acorns) traditionally consumed by Pima Indians. Equivalent carbohydrate portions (25 g) of the foods were fed to eight healthy Caucasian volunteers. The calculated glycemic indices (GIs) (mean +/- SEM with glucose as the standard) were all low, ranging from 16 +/- 2 for acorns to 40 +/- 5 for corn. Insulin responses and in vitro starch digestibilities correlated with the GI. These results provide further support for the hypothesis that the slow digestion and absorption of starch in traditional foods was a factor that helped protect susceptible populations from developing diabetes.     

Effect of fenugreek seeds and leaves on blood glucose and serum insulin responses in human subjects

Fenugreek (Trifolium foenum graecum) a leguminous herb, is extensively cultivated in India, Mediterranean region and North Africa. It is used for culinary and medicinal purposes and also for fodder in various parts of the world. The hypoglycemic effect of fenugreek seeds and leaves was tested in normal and diabetic subjects. Six protocols A, B, C, D, E and F involved the acute administration (single dose of 25 g of seeds, 5 g of gum isolate and 150 g of leaves) of whole fenugreek seeds, defatted fenugreek seeds, gum isolate, degummed fenugreek seeds, cooked fenugreek seeds and cooked fenugreek leaves to healthy subjects. The rise in plasma glucose after a dose of glucose or meal was prevented by fenugreek seeds. The serum insulin levels were also modified (P<0.05). The reduction in area under glucose curve was greatest with whole seeds (42.4%), followed by gum isolate (37.5%), extracted seeds (36.9%), and cooked seeds (35.1%) in that order. The degummed seeds and fenugreek leaves showed little effect on glycemia. Fenugreek seeds were also administered for 21 days to diabetic subjects. A significant imporvement in plasma glucose and insulin responses was observed in these subjects. The 24 hr urinary glucose output and serum cholesterol levels were also reduced (P<0.05).     

Effects on blood glucose,insulin, lipid and proatherosclerotic parameters in stable type 2 diabetic subjects during an oral fat challenge

Background  

Restriction of fat intake has been effective in improving insulin sensitivity in obese and type 2 diabetic subjects, but what effects the recommended diet (less than 30% of total calories from fat) have not been elucidated in subjects with type 2 diabetes. The purpose of this study was to test the effects of oral fat challenge, composing 30% calories of a meal, on blood glucose, insulin, lipid, leptin, plasminogen activator inhibitor-1 (PAI-1) and tumor necrosis factor-α (TNF-α).     

仙鹤草对糖尿病大鼠血糖胰岛素水平的影响

目的观察仙鹤草对糖尿病大鼠血糖、胰岛素水平影响的动态变化,为抗糖尿病药物的开发提供依据。方法选择雄性SD大鼠,腹腔注射链脲佐菌素(streptozotocin,STZ)建立糖尿病大鼠动物模型。将造模成功的糖尿病大鼠随机分为糖尿病模型组,仙鹤草低剂量组(60 g/kg)、仙鹤草高剂量组(120 g/kg),每天经口灌胃,连续4周,另设正常对照组。观察仙鹤草对糖尿病大鼠体重、血糖及血清胰岛素水平的影响的动态变化,实验结束后取胰腺用10%甲醛溶液固定,做病理组织学检查。结果实验结束时,糖尿病模型组大鼠血糖、胰岛素水平分别为(17.55±6.08)mmol/L和(7.53±2.15)μU/ml,仙鹤草低、高剂量组胰岛素水平分别为(16.79±6.81)μU/ml和(18.29±7.15)μU/ml,显著高于糖尿病纽(P0.01);血糖水平分别为(4.71±2.19)mmol/L和(3.92±1.17)mmol/L,显著低于糖尿病组(P0.01)。结论仙鹤草可通过增加胰岛素分泌发挥降糖作用。     

Effect of source of dietary fats on serum glucose, insulin, and gastric inhibitory polypeptide responses to mixed test meals in subjects with non-insulin dependent diabetes mellitus

We recently demonstrated that normal subjects given mixed test meals of varying fatty acid composition showed significantly greater serum insulin responses to meals enriched with polyunsaturated fat as compared to those in which the fat content was derived from saturated fatty acids. To determine if a similar phenomenon occurs in subjects with non-insulin dependent diabetes mellitus (NIDDM), serum glucose, insulin, C-peptide, and gastric inhibitory polypeptide (GIP) responses to three mixed test meals of varying fatty acid composition were assessed in twelve subjects with NIDDM. Baseline means (+/- SEM) fasting serum glucose concentration was 205 +/- 15 mg/dl and mean glycosylated hemoglobin was 8.5 +/- 0.5%. Fatty acids in the test meals were either saturated fats, or polyunsaturated fats derived from vegetables or fish. Each test meal provided 40% of the subjects' calculated daily caloric requirement and contained approximately 45% carbohydrate, 40% fat, and 15% protein. No appreciable differences in serum glucose, insulin, and C-peptide responses occurred during the three mixed test meals. Although GIP values were higher in the saturated fat and the vegetable meals when compared to the fish meal, the differences did not reach statistical significance. The inability of NIDDM subjects to evoke a greater insulin response to polyunsaturated fatty acids than to saturated fatty acids suggests another pathogenetic factor contributing to their glucose intolerance.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of Amla fruit (Emblica officinalis Gaertn.) on blood glucose and lipid profile of normal subjects and type 2 diabetic patients

The present study evaluated the anti-hyperglycemic and lipid-lowering properties of Emblica officinalis Gaertn. fruit in normal and diabetic human volunteers. The results indicated a significant decrease (P < 0.05) in fasting and 2-h post-prandial blood glucose levels on the 21st day in both normal and diabetic subjects receiving 1, 2 or 3 g E. officinalis powder per day as compared with their baseline values. Significant (P < 0.05) decreases were also observed in total cholesterol and triglycerides in both normal and diabetic volunteers on day 21 that were given either 2 or 3 g E. officinalis powder per day. However, diabetic volunteers receiving only 3 g E. officinalis powder exhibited a significant (P < 0.05) decrease in total lipids on day 21. Both normal and diabetic volunteers receiving 2 or 3 g E. officinalis powder significantly (P < 0.05) improved high-density lipoprotein-cholesterol and lowered low-density lipoprotein-cholesterol levels.     

Effect of Amla fruit (Emblica officinalis Gaertn.) on blood glucose and lipid profile of normal subjects and type 2 diabetic patients

The present study evaluated the anti-hyperglycemic and lipid-lowering properties of Emblica officinalis Gaertn. fruit in normal and diabetic human volunteers. The results indicated a significant decrease (P < 0.05) in fasting and 2-h post-prandial blood glucose levels on the 21st day in both normal and diabetic subjects receiving 1, 2 or 3 g E. officinalis powder per day as compared with their baseline values. Significant (P < 0.05) decreases were also observed in total cholesterol and triglycerides in both normal and diabetic volunteers on day 21 that were given either 2 or 3 g E. officinalis powder per day. However, diabetic volunteers receiving only 3 g E. officinalis powder exhibited a significant (P < 0.05) decrease in total lipids on day 21. Both normal and diabetic volunteers receiving 2 or 3 g E. officinalis powder significantly (P < 0.05) improved high-density lipoprotein-cholesterol and lowered low-density lipoprotein-cholesterol levels.     

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.     

Hepatic insulin resistance in obese non-diabetic subjects and in type 2 diabetic patients

OBJECTIVE: Obese non-diabetic patients are characterized by an extra-hepatic insulin resistance. Whether obese patients also have decreased hepatic insulin sensitivity remains controversial. RESEARCH METHODS AND PROCEDURES: To estimate their hepatic insulin sensitivity, we measured the rate of exogenous insulin infusion required to maintain mildly elevated glycemia in obese patients with type 2 diabetes, obese non-diabetic patients, and lean control subjects during constant infusions of somatostatin and physiological low-glucagon replacement infusions. To account for differences in insulin concentrations among the three groups of subjects, an additional protocol was also performed in healthy lean subjects with higher insulin infusion rates and exogenous dextrose infusion. RESULTS: The insulin infusion rate required to maintain glycemia at 8.5 mM was increased 4-fold in obese patients with type 2 diabetes and 1.5-fold in obese non-diabetic patients. The net endogenous glucose production (measured with 6,6-(2)H(2)-glucose) and total glucose output (measured with 2-(2)H(1)-glucose) were approximately 30% lower in the patients than in the lean subjects. Net endogenous glucose production and total glucose output were both markedly increased in both groups of obese patients compared with lean control subjects during hyperinsulinemia. DISCUSSION: Our data indicate that both obese non-diabetic and obese type 2 diabetic patients have a blunted suppressive action of insulin on glucose production, indicating hepatic and renal insulin resistance.     

Effect of source of dietary fats on serum glucose,insulin, and gastric inhibitory polypeptide responses to mixed test meals in subjects with non-insulin dependent diabetes mellitus.

We recently demonstrated that normal subjects given mixed test meals of varying fatty acid composition showed significantly greater serum insulin responses to meals enriched with polyunsaturated fat as compared to those in which the fat content was derived from saturated fatty acids. To determine if a similar phenomenon occurs in subjects with non-insulin dependent diabetes mellitus (NIDDM), serum glucose, insulin, C-peptide, and gastric inhibitory polypeptide (GIP) responses to three mixed test meals of varying fatty acid composition were assessed in twelve subjects with NIDDM. Baseline means (+/? SEM) fasting serum glucose concentration was 205 +/? 15 mg/dl and mean glycosylated hemoglobin was 8.5 +/? 0.5%. Fatty acids in the test meals were either saturated fats, or polyunsaturated fats derived from vegetables or fish. Each test meal provided 40% of the subjects' calculated daily caloric requirement and contained approximately 45% carbohydrate, 40% fat, and 15% protein. No appreciable differences in serum glucose, insulin, and C-peptide responses occurred during the three mixed test meals. Although GIP values were higher in the saturated fat and the vegetable meals when compared to the fish meal, the differences did not reach statistical significance. The inability of NIDDM subjects to evoke a greater insulin response to polyunsaturated fatty acids than to saturated fatty acids suggests another pathogenetic factor contributing to their glucose intolerance.(ABSTRACT TRUNCATED AT 250 WORDS)     

Plasma amino acid, glucose, and insulin responses to moderate-protein and high-protein test meals in pregnant, nonpregnant, and gestational diabetic women

Test meals providing two levels of dietary protein (13% or 26% of the energy) were fed to eight pregnant (P), nine nonpregnant (NP), and two gestational diabetic (GDM) women. Plasma levels of amino acids were measured at 0 h and 2 h. Glucose and insulin were measured at 0, 1/2, and 2 h after the meals. In the fasting state, P women had significantly lower fasting concentrations of most of the amino acids. After the high-protein meal, rises of arginine, ornithine, and branched-chain amino acids (BCAAs: leucine, isoleucine, and valine), were significantly smaller in P women. Changes in BCAAs were normal in GDM women. P women had greater rises of insulin in response to both test meals than did NP women. This may facilitate increased BCAA uptake from the circulation. Rises in plasma glucose tended to be higher in P than NP women, suggesting that insulin's effects on glucose and BCAA uptake may be mediated separately.