维吾尔族常用传统食品和血糖生成指数测定

目的确定新疆维吾尔族常用传统食品的种类,测定其血糖生成指数（GI）。方法运用食物频率调查法进行问卷调查确定维吾尔族传统特色食品;根据食物碳水化合物的含量计算含有50克碳水化合物的食物量,用50克葡萄糖为对照量。受试者民族为维吾尔族,共分4个批次,每个批次为10人,测定他们的空腹血糖后服用试验物,测定2h内不同时点的血糖水平。根据Wolver方法计算食物的GI值。结果确定了15种新疆维吾尔族特色食品,并测定了其GI值。结论GI数据从一定程度上提示新疆维吾尔族糖尿病高发的原因。     

复配式粗杂粮的营养成分特征及其对人体血糖生成的影响

目的评价复配式粗杂粮的营养成分及其血糖生成指数(GI),探讨其营养成分与生物功效的关系。方法按国家标准方法分别测定复配式粗杂粮及对照食物一般营养素含量。取含有50g碳水化物的复配式粗杂粮制成馒头,50g葡萄糖为对照物,10名志愿者测空腹血糖后,服用2种食品,测定3h内不同时间的血糖水平,依照Wolver方法计算食物的GI值。结果复配式粗杂粮每100g中含不溶性膳食纤维(粗纤维)13·7g、维生素B10·40mg、蛋白质13·5g、灰分2·0g、维生素B20·16mg、钙54mg、铁7·1mg、锌3·00mg。其餐后血糖绝对增加值和血糖反应曲线下增值面积显著低于葡萄糖(P<0·05),GI值为52·6。结论复配式粗杂粮中较高含量的蛋白质、矿物质、粗纤维和维生素B1、B2,特别是比较低的GI是复合式营养干预取得较好效果的重要原因。     

低糖高纤维类食物的血糖生成指数

目的:测定常见的坚果类、蔬果类等低糖类食物血糖指数值(GI),并探讨食物中糖的种类、脂肪、蛋白质和膳食纤维含量对于血糖指数以及血糖应答的影响.方法:根据Wolver方法计算食物的GI值,由于非谷薯类的糖类含量不足10%,故多数食物用含25 g糖类的食物重量计算;并用25 g葡萄糖作参照物.结果:测定了13种食物的GI值,并有膳食纤维与GI值负相关.结论:影响低糖类食物GI的因素并非是糖的种类(直链或支链),而是膳食纤维含量.     

基于血糖负荷概念的食物交换份在糖尿病营养治疗中的应用

目的:建立以控制血糖负荷和总能量为特征,体现食物血糖应答差异的新型食物交换系统,探索其在糖尿病人饮食管理中的应用价值。方法:根据食物血糖指数(glycemicindex,GI)与碳水化物含量计算血糖负荷(glycemicload,GL),比较GI与GL的相关性以及对食物血糖效应的影响。融合GL和食物交换份方法的特点,提出基于GL的新型食物交换份。结果:粮谷类、豆类及制品的GI与GL%有较好的一致性,相关系数分别为0.64、0.55。而蔬菜、水果类食物的GI与GL%无明显相关性。基于GL的食物交换份既保留了传统交换方法简单易行的特点,又充分考虑了碳水化物在质和量方面的差异,有助于在控制总能量的同时,定量预测或调整混合膳食的血糖应答效应。结论:基于GL的食物交换份有较高的应用前景,值得实践和推广。     

大豆发酵制品唐可肽对血糖生成指数的影响

目的测定大豆发酵制品唐可肽的血糖生成指数,并探讨唐可肽对于血糖生成指数以及血糖应答的影响。方法根据唐可肽碳水化合物的含量计算出相当于25g碳水化合物的唐可肽量,用25g葡萄糖为对照量,将受试者分为唐可肽组和葡萄糖组,每组10人,测定他们的空腹血糖后分别服用唐可肽和葡萄糖,测定2h内不同时点的血糖水平。根据Wolver方法计算食物的血糖生成指数(GI)值。结果测定了唐可肽血糖生成指数为54.86。结论唐可肽为低血糖生成指数值的食物。具有很好的降血糖、平稳血糖的作用。     

食物与血糖

<正> 食物的血糖生成指数(GI)可以反应其是否有益于控制血糖,它表示50克碳水化物和50克葡萄糖食入后血糖上升值的百分比。某些食物进入胃肠后,消化吸收快,血糖升高快,则GI值高;反之一些食物消化吸收慢,血糖上升慢,则GI值低。GI<55的食品及搭配食品是糖尿病者的有益食谱,GI>70则是糖尿病者的不利食谱。GI的研究为糖尿病者     

抓饭和馕的血糖生成指数与胰岛素指数

我们测定了新疆少数民族常用主食抓饭和馕的血糖生成指数(GI)与胰岛素指数(Ⅱ),现报道如下。1.对象与方法:10名空腹健康志愿者分别试食含碳水化合物50g的葡萄糖粉、抓饭和馕,进行葡萄糖耐量试验和受试物糖耐量试验,应用国际认可的标准化测定法测定空腹及餐后15、30、45、60、90、120min时血浆中血糖和胰岛素水平[1]。GI值和胰岛素指数(Ⅱ)值的计算由Microscoft Excel2000软件完成,采用方差分析或t检验进行显著性检验,显著性界值定为0.05。2.结果:(1)受试物GI值和Ⅱ值:以葡萄糖为参照物(GI=100),受试物馕GI值为93.28±21.50,Ⅱ值为93.12…     

测量食物生糖指数的方法学研究

食物生糖指数(GI)概念的提出旨在按照食物餐后血糖应答的不同来区分各种来源的碳水化合物食物。然而各种研究在获取GI值的方法学上存在差异,本文就GI测定过程如受试者选取、受试食物、测定过程、统计分析及计算方法等方面涉及的相关方法学研究进行综述,并对GI测定过程中的技术问题提出建议。     

074 测量食物生糖指数的方法学研究

食物生糖指数(GI)概念的提出旨在按照食物餐后血糖应答的不同来区分各种来源的碳水化合物食物.然而各种研究在获取GI值的方法学上存在差异,本文就GI测定过程如受试者选取、受试食物、测定过程、统计分析及计算方法等方面涉及的相关方法学研究进行综述,并对GI测定过程中的技术问题提出建议.     

食醋添加量、水分含量及食物颗粒对血糖应答的影响

目的通过食醋添加量、水分含量及食物颗粒的不同配比对玉米粥餐后血糖应答的影响,探讨调整理化因素对降低餐后血糖应答的有效性和可行性。方法以食醋添加量、水分含量及食物颗粒为因素进行三因素三水平有交互作用的正交试验,募集18名健康男性志愿者,分别试食含40g可利用碳水化合物的葡萄糖粉和18种不同配比的玉米粥,测定120min内的血糖生成指数(GI)、胰岛素指数(II)和饱腹感指数(SI),比较各水平组合下各值的差异。结果食物颗粒是GI和II的最大影响因素,食醋添加量是SI最大的影响因素;方差分析显示食物颗粒对GI结果有显著性影响(F=3.858,P<0.05),小颗粒产生的GI值大于大颗粒与中颗粒;水分含量对II的影响有显著性(F=5.750,P<0.01),20∶1水平的II最高;食醋添加量对SI的影响有显著性(F=3.37,P<0.05),16ml水平的SI最大。结论选择较大食物颗粒、适量添加食醋、减少食物中的水分可以有助于降低餐后血糖应答。     

Glycemic index of single and mixed meal foods among common Japanese foods with white rice as a reference food

OBJECTIVE: The objectives were to examine the feasibility of using white rice as a reference food in the study of glycemic index (GI) and to examine the GI values of both single and mixed meal foods among rice species, processed rice products, beans, and dairy products. DESIGN: Subjects were served with 50 g carbohydrate content of white rice at least two times (maximum three times) and test food once after separate overnight fasts. Capillary blood glucose measurements were carried out before and during 120 min after each food load. SETTING: The study was carried out in an outpatient setting. SUBJECTS: A total of 58 (38 females and 20 males) nondiseased subjects, mean aged 37 y and mean BMI 22 kg/m(2) were included. RESULT: The correlation between incremental area under curve of white rice and glucose was r=0.853 (n=10, P <0.0001) and white rice was considered suitable to be used as a reference food. Among mixed meal foods, the combination of carbohydrate foods with vinegar, dairy products, and bean products significantly decreased the GI value of white rice of 20-40%. The reduction of GI occurred whether the foods were taken together, before or after rice intake. GI of noodles such as udon, soba, and spaghetti showed low GI values. CONCLUSION: White rice could be used as a reference food in determining GI values of foods. A total of 32 single and mixed meal Japanese common food products were examined for their GI values.     

谷物淀粉的慢消化特性与餐后血糖应答

目的分析不同谷物淀粉的慢消化性能与餐后血糖应答。方法采用Englyst方法对淀粉进行体外营养学分类,同时10名空腹健康志愿者分别试食含碳水化合物50g的葡萄糖粉与不同淀粉,测餐后120min血浆中血糖水平并计算出血糖生成指数(GI)与增加血糖生成指数(EGI)值。结果在碳水化合物分类中谷物淀粉中主要含有SDS,约为50%。以葡萄糖GI为100%,不同谷物淀粉的GI均大于90%,属于高GI食品,但是其EGI均为正数。结论不同谷物的淀粉都有良好的慢消化性能与相似的餐后血糖应答,它们吸收缓慢而持久,可维持餐后血糖稳态,对健康有利。     

Influence of training status on glycemic index

The glycemic index (GI) represents the relative postprandial blood glucose response to the ingestion of a food containing carbohydrate. Although regular physical exercise may influence glucose metabolism, it is not yet known if chronically performed exercise also affects the GI. The objective of this study was, therefore, to determine the GI of common meals (three breakfast cereals: B, C, D) in healthy, nonsmoking young males 2 who were either endurance-trained (n = 12) or sedentary (n = 11). Glucose was used as the reference food. The GI value between the endurance-trained and sedentary subjects differed significantly (p < 0.01). Pair-wise comparisons between endurance-trained and sedentary subjects within the different test meals were significant for test meal D (p = 0.002), marginally non-significant for meal C (p = 0.052) and not significant for meal B (p = 0.204). These results suggest that the GI of some complex foods may depend on the training status of healthy young subjects.     

Digestion rate of legume carbohydrates and glycemic index of legume-based meals

A study was performed to examine the rate of digestion of available carbohydrate in legumes and its mixtures with cereals, prepared as commonly eaten. The legumes and cereals studied were lentil (Lens sculenta), pea (Pisum sativum), bean (Phaseolus vulgaris, var tortola), rice (Oryza sativa) and spaghetti. Foods were purchased at the city market. Total starch content and the carbohydrate digestion rates were determined using the enzymatic method proposed by Englyst et al. Total starch levels ranged from 7.78 g/100 g in cooked flour bean to 20.6 g/100 g in a bean-spaghetti dish, and dietary fiber contents ranged from 2.4 g/100 g in a cooked 70:30 lentil-rice mixture to 5.26 g/100 g in a cooked whole bean. The rapid digestion rate carbohydrates showed values from 4.8 in the bean soup to 8.9 in the bean-spaghetti combination. The same results show, expressed as rapid available glucose (RAG), the amount of rapid carbohydrate/100 g food or meal as eaten, and as the starch digestion index (SDI), the percentage of rapid carbohydrate digestion rate in relation to the total amount of carbohydrate. The RAG values ranged between 5.0 for cooked beans and 10 for cooked beans and spaghetti, and the SDI ranged between 40 for cooked pea flour and 62 for cooked bean flour. Legumes prepared as soup showed a higher rapid digestion rate than legumes prepared as whole grain. The bean-spaghetti based-meal and the lentil-based meal showed glycemic index mean and standard deviation values of 76.8 +/- 43.4 and 49.3 +/- 29.5, RAG values of 7.0 and 6.0, and SDI values of 57 and 54, respectively. The knowledge of the importance of the carbohydrate digestion rates in human health in increasing, and probably will soon be used in the development of the food pyramid. The foods with a moderate fraction of rapid digestion rate, such as legumes, should be included in the base of the pyramid.     

<Emphasis Type="Italic">In vitro</Emphasis> starch digestibility and <Emphasis Type="Italic">in vivo</Emphasis> glucose response of gluten–free foods and their gluten counterparts

BACKGROUND: Recently there has been increasing interest in the production of gluten-free (GF) foods and studies on minor cereals and pseudocereals without celiac activity in order to fulfill the specific needs of people affected by celiac disease. GF bread, pasta, biscuits are usually manufactured using different combinations of thickenings and particular food processing procedures that could affect starch digestibility. Carbohydrates, mainly starch from cereals, play an important part in a balanced diet, and dietary guidelines suggest a diet with low glycemic index foods, that is to say rich in slowly digested carbohydrates. AIM: The present study was aimed at evaluating: 1) the importance of some GF food characteristics in relation to their effects on in vitro starch accessibility to digestion, in comparison with traditional gluten products; 2) the in vivo metabolic responses to GF foods. METHODS: Firstly, starch digestibility of several products was evaluated in vitro. Then, an in vivo study was performed on a group of healthy volunteers. Postprandial glucose and insulin responses were evaluated after administration of three GF foods and traditional bread. Triglycerides and free fatty acids (FFA) were also evaluated. Attempts were also made to explore differences in metabolic responses to GF foods in healthy subjects with respect to celiac subjects. RESULTS: The area under the curve (AUC) of digested starch of GF bread was slightly higher than that of the traditional counterpart. No significant difference was observed in AUCs of digested starch between GF pasta and the traditional pasta. The AUCs of digested starch of quinoa and the two samples of pasta were not statistically different. Significant differences were observed between GF bread and bread-like products. Statistic differences in glucose responses to GF pasta were observed between healthy and celiac subjects. In healthy subjects, the AUCs of glucose response after GF bread were higher than those after bread with gluten. No significant differences were observed between the AUCs of insulin responses to all products tested. Glycemic index (GI) for GF pasta was similar to GI for GF bread while GI for quinoa was slightly lower than that of GF pasta and bread. Two-way ANOVA revealed that quinoa induced lower FFA levels with respect to GF pasta. In addition, triglyceride concentrations were significantly reduced for quinoa with respect to GF bread and bread. CONCLUSIONS: Our results indicate that the different formulations and the food processing procedures used in the manufacturing of GF products may affect the rate of starch digestion both in vitro and in vivo. It may be worthwhile improving the formulation of these products. Furthermore, quinoa seems to represent a potential alternative to traditional foods, even if further and larger studies are required to demonstrate its hypoglycemic effects.     

Glycemic index and glycemic load: measurement issues and their effect on diet-disease relationships

Glycemic index (GI) describes the blood glucose response after consumption of a carbohydrate containing test food relative to a carbohydrate containing reference food, typically glucose or white bread. GI was originally designed for people with diabetes as a guide to food selection, advice being given to select foods with a low GI. The amount of food consumed is a major determinant of postprandial hyperglycemia, and the concept of glycemic load (GL) takes account of the GI of a food and the amount eaten. More recent recommendations regarding the potential of low GI and GL diets to reduce the risk of chronic diseases and to treat conditions other than diabetes, should be interpreted in the light of the individual variation in blood glucose levels and other methodological issues relating to measurement of GI and GL. Several factors explain the large inter- and intra-individual variation in glycemic response to foods. More reliable measurements of GI and GL of individual foods than are currently available can be obtained by studying, under standard conditions, a larger number of subjects than has typically been the case in the past. Meta-analyses suggest that foods with a low GI or GL may confer benefit in terms of glycemic control in diabetes and lipid management. However, low GI and GL foods can be energy dense and contain substantial amounts of sugars or undesirable fats that contribute to a diminished glycemic response. Therefore, functionality in terms of a low glycemic response alone does not necessarily justify a health claim. Most studies, which have demonstrated health benefits of low GI or GL involved naturally occurring and minimally processed carbohydrate containing cereals, vegetables and fruit. These foods have qualities other than their immediate impact on postprandial glycemia as a basis to recommend their consumption. When the GI or GL concepts are used to guide food choice, this should be done in the context of other nutritional indicators and when values have been reliably measured in a large group of individuals.     

The glycemic load estimated from the glycemic index does not differ greatly from that measured using a standard curve in healthy volunteers

Glycemic load (GL) is calculated indirectly as glycemic index (GI) times the weight of available carbohydrate. Alternatively, GL may be measured directly using a standard glucose curve. The purpose of this study was to test the agreement between GL values obtained using direct and indirect methods of measurement in 20 healthy volunteers. A standard curve in which glucose dose was plotted against blood glucose incremental area under the curve (iAUC) was generated using beverages containing 0, 12.5, 25, 50, and 75 g glucose. The GI and available carbohydrate content of 5 foods were measured. The foods (white bread, fruit bread, granola bar, instant potato, and chickpeas) were consumed in 3 portion sizes, yielding 15 food/portion size combinations. GL was determined directly by relating the iAUC of a test food to the glucose standard curve. For 12 of 15 food/portion size combinations, GL determined using GI x available carbohydrate did not differ from GL measured from the standard curve (P > 0.05). For 3 of the test products (100 g white bread, and 100- and 150-g granola bars), GI x available carbohydrate was higher than the direct measure. Benefits of the direct measure are that the method does not require testing for available carbohydrate and it allows portion sizes to be tested. For practical purposes, GI x available carbohydrate provided a good estimate of GL, at least under circumstances in which available carbohydrate was measured, and GI and GL were tested in the same group of people.     

Glycemic index of American-grown jasmine rice classified as high

The primary objective was to determine the glycemic index (GI) of jasmine rice grown in the United States (US). Secondary objective was to compare the GI of US grown jasmine rice to those grown in Thailand. Twelve healthy subjects were served all four brands of jasmine rice and a reference food (glucose), each containing 50?g of available carbohydrate. Fingerstick blood glucose was measured at 0, 15, 30, 45, 60, 90, and 120?min after consumption following a fasting state. The GI was calculated using the standard equation. The GI values for test foods ranged from 96 to 116 and were all classified as high GI foods. No difference in GI was found between American-grown and Thailand-grown jasmine rice. Although not statistically significant, observations show glycemic response among Asian American participants may be different. GI should be considered when planning meals with jasmine rice as the main source carbohydrate.     

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.     

Determination of the glycaemic index of various staple carbohydrate-rich foods in the UK diet

OBJECTIVE: To determine the glycaemic index (GI) of various staple carbohydrate-rich foods in the UK diet, and to consider the factors influencing the GI of foods. DESIGN: Subjects were served with 25 or 50 g portions of glucose on three occasions, followed by a selection of test foods providing an equal amount of available carbohydrate, in random order. Each test food was consumed by 10 subjects. Capillary blood glucose levels were measured in the fasted state and over the 120 min following commencement of consumption of the foods. SETTING: The study was carried out in a research institute (MRC Human Nutrition Research, Cambridge, UK). SUBJECTS: Forty-two healthy adult volunteers were studied. METHODS: The GI values of 33 foods were measured according to the WHO/FAO recommended methodology. These foods included various breads, breakfast cereals, pasta, rice and potatoes, all of which were commercially available in the UK. CONCLUSIONS: The results illustrate a number of factors which are important in influencing the GI of a food, highlighting the importance of measuring the GI of a food, rather than assuming a previously published value for a similar food. This is useful both to researchers analysing dietary surveys or planning intervention studies, and also to health professionals advising individuals on their diets.