Correlation between saliva glycated and blood glycated proteins

Objectives Blood and saliva samples were obtained to examine if there is a correlation between saliva glycated protein and blood glycated protein. Methods Blood and saliva samples of 51 male workers were collected. The fructosamine and hydrazine methods were used to measure saliva glycated protein. HbA1c, fructosamine and blood glucose were measured as indices of blood glycated protein, and the correlation between blood glycated protein and saliva glycated protein was examined. Results Saliva fructosamine glycated protein showed a significant correlation with HbA1c and blood glucose (r=0.449; p=0.001 and r=0.445; p=0.001, respectively). No correlation was identified between saliva hydrazine glycated protein and the index of blood glycated protein. Conclusions Blood glycated protein and blood glucose could be estimated by measuring saliva glycated protein.     

Dietary glycaemic load and intakes of carbohydrates, fats and proteins in 1040 hospitalised adult Chinese subjects

Metabolic diseases in China have been on the rise during recent decades. To investigate dietary glycaemic load (GL) and its correlation with the prevalence of metabolic diseases in hospitalised Chinese adults, we analysed the total energy and macronutrient intakes in 1040 patients. Dietary GL was calculated based upon glycaemic index (GI), carbohydrate content and daily intake of individual foods. Dietary patterns at different dietary GL levels and the distribution of dietary GL were analysed in patients from the internal medical departments v. those from surgical departments. Height and weight were measured using a standardised protocol. The present study results demonstrated that in hospitalised adults, 95·5?% of dietary GL came from cereals. Average GL was higher in male patients than in female patients, and was higher in patients from surgical departments than in patients from medical departments. Patients with lower dietary GL consumed inadequate carbohydrates and excessive fats, and therefore had a higher prevalence of overweight and obesity. Dietary GL analysis may be helpful to nutrition assessment and rational diet intervention in hospitalised Chinese patients.     

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.     

Dietary carbohydrates and the colonic microflora

The world of the colonic microflora has lain dormant in recent years, but is coming alive now with the advent of new chemical and molecular technologies for identifying bacteria, and the emergence of the concepts of biofilms, pro- and prebiotics. That bacteria play an essential role in barrier resistance to infection, ulcerative colitis and colorectal cancer is slowly becoming clear. New potential therapeutic avenues using bacteria should soon start to open up. Scientifically we lack an understanding of the mechanisms at work.     

Dietary carbohydrates and insulin sensitivity

This review considers recent findings and ideas on the impact of dietary carbohydrates on insulin sensitivity in the context of the prevention of diabetes and cardiovascular disease. We assess the evidence for benefits in insulin sensitivity following high starch as distinct from high sucrose intakes when the diet is low in fat. We consider relationships between obesity, leptin and carbohydrate intake. We conclude that reducing the rate of carbohydrate digestion in the small bowel may be the key stage at which to intervene to reduce insulinaemia and so prevent downregulation of insulin receptors and insulin resistance.     

Dietary carbohydrates and insulin action in humans

The metabolic syndrome represents a vicious cycle whereby insulin resistance leads to compensatory hyperinsulinaemia, which maintains normal plasma glucose but may exacerbate insulin resistance. Excess insulin secretion may eventually reduce beta-cell function due to amyloid deposition, leading to raised blood glucose and further deterioration of beta-cell function and insulin sensitivity via glucose toxicity. Reducing postprandial glucose and insulin responses may be a way to interrupt this process, but there is disagreement about the dietary approach to achieve this. Glucose and insulin responses are determined primarily by the amount of carbohydrate consumed and its rate of absorption. Slowly absorbed, low glycaemic-index (GI) foods are associated with increased HDL cholesterol and reduced risk of type 2 diabetes. There is some evidence that low-GI foods improve insulin sensitivity in humans, although studies using established techniques (glucose clamp or frequently sampled intravenous glucose tolerance test) have not been done. Low carbohydrate diets have been suggested to be beneficial in the treatment of the metabolic syndrome because of reduced postprandial insulin. However, they may increase fasting glucose and impair oral glucose tolerance--effects which define carbohydrate intolerance. The effects of low carbohydrate diets on insulin sensitivity depend on what is used to replace the dietary carbohydrate, and the nature of the subjects studied. Dietary carbohydrates may affect insulin action, at least in part, via alterations in plasma free fatty acids. In normal subjects a high-carbohydrate/low-GI breakfast meal reduced free fatty acids by reducing the undershoot of plasma glucose, whereas low-carbohydrate breakfasts increased postprandial free fatty acids. It is unknown if these effects occur in insulin-resistant or diabetic subjects. Thus further work needs to be done before a firm conclusion can be drawn as to the optimal amount and type of dietary carbohydrate for the treatment of the metabolic syndrome.     

Glycaemic and insulinaemic indices of Mexican foods high in complex carbohydrates in Type 2 diabetic subjects

The glycaemic (GI) and insulinaemic indices (InIn) of 3 indigenous single foods and 3 indigenous realistic high complex carbohydrate meals (bread=100) were determined in 7 Mexican type 2 diabetic subjects. Observed GI (mean+/-SEM) were: beans (B) 39.9+/-7.3, wheat tortilla (WT) 53.2+6.4, corn tortilla (CT) 84.8+/-6.0, wheat tortilla beans taco (BWT) 71.2+/-9.5, corn tortilla beans taco (BCT) 73.5+/-4.3 and corn tortilla potato taco (PT) 121.5+/-12.8. The GI of white bread (WB) was higher than B (p<0.01), WT (p<0.01), BWT (p<0.05) and BCT (p<0.05) and did not differ from CT and PT. Observed InIn were: B 36.2+/-7.0, WT 49+/-5.6, CT 83.4+/-17.6, BWT 66.1+/-5.9, BCT 80.3+/-7.9 and PT 164.2+/-26.5. InIn of B, WT and BWT were lower than WB (p<0.01), whereas PT was higher (p<0.05) and CT and BCT did not differ. Diabetic subjects do not have to eliminate WT, B or beans tacos, as suggested by some physicians. Nevertheless, they could lower the consumption of CT and PT. This information presents an alternative to diabetic subjects to live and eat more freely, by preventing the alteration of familiar and dining cultural habits.     

Dietary carbohydrates and triacylglycerol metabolism.

There is a growing body of scientific evidence which demonstrates that plasma triacylglycerol (TAG) concentration, especially in the postprandial state, is an important risk factor in relation to the development of CHD. Postprandial hypertriacylglycerolaemia is associated with a number of adverse metabolic risk factors, including the preponderance of small dense LDL, low HDL-cholesterol concentrations and elevated factor VII activity. Traditionally, a low-fat high-carbohydrate diet was used to prevent CHD because it effectively reduces plasma cholesterol concentrations, but this dietary regimen increases plasma TAG concentrations and reduces HDL-cholesterol concentrations. There is substantial epidemiological evidence which demonstrates that high plasma TAG and low plasma HDL concentrations are associated with an increased risk of CHD. Thus, there is reason for concern that the adverse effects of low-fat high-carbohydrate diets on TAG and HDL may counteract or negate the beneficial effect of reducing LDL-cholesterol concentrations. Although there have been no prospective studies to investigate whether reduced fat intake has an adverse effect on CHD, there is strong epidemiological evidence that reducing total fat intake is not protective against CHD. On the other hand, high-fat diets predispose to obesity, and central obesity adversely affects TAG metabolism. There is substantial evidence that in free-living situations low-fat high-carbohydrate diets lead to weight loss, which in turn will correct insulin resistance and plasma TAG metabolism. Clearly there is a need for prospective studies to resolve the issue as to whether low-fat high-carbohydrate diets play an adverse or beneficial role in relation to the development of CHD.     

Dietary fibre, lente carbohydrates and the insulin-resistant diseases

Several epidemiological studies link consumption of fibre-rich foods to a reduced risk of type 2 diabetes and CHD. The 'fibre hypothesis' suggested that this was a direct effect of fibre. However, fibre-rich foods contain different types of fibre as well as other potentially beneficial compounds, and many foods naturally high in fibre have low glycaemic and insulinaemic indices, possibly due to food form. The question therefore emerges as to the effect of isolated fibre per se on insulin sensitivity, lipids and other risk factors associated with the metabolic syndrome. Many beneficial effects are seen with pharmacological doses of isolated viscous soluble fibre, including improved insulin sensitivity, decreased LDL-cholesterol levels and decreased clotting factors. Similar effects are seen with low glycaemic-index foods. In contrast, insoluble non-viscous cereal fibre is not seen to act directly on risk factors when taken in refined foods such as in milled flour. Since cereal fibre, the major type of fibre in western diets, does not directly act on the risk factors for the metabolic syndrome, the question remains as to possible mechanisms. Until now, fibre and the nature and processing of the starch and particle size have been seen as the main determinants of the metabolic response to starchy foods. However, fibre-rich foods also have an increased protein-to-carbohydrate ratio. Hence we suggest that the protective effect of fibre may also be due to increased vegetable protein content, which may act directly to reduce clotting factors and oxidized LDL-cholesterol levels.     

Effects of fructo-oligosaccharides on blood glucose and serum lipids in diabetic subjects

Daily intake of 8.0 g per day of fructo-oligosaccharides for fourteen days significantly reduced mean fasting blood glucose levels by 15 mg/dl, mean serum total cholesterol levels by 19 mg/dl and LDL-cholesterol levels by 17 mg/dl in diabetic subjects (n=18), while the control diabetic subjects (n=10) who were given 5.0 g per day of sucrose showed no significant changes. The levels of serum HDL-cholesterol, triglycerides or free fatty acids were not significantly affected either by fructo-oligosaccharides or sucrose. These results indicate that the daily intake of fructo-oligosaccharides ameliorates the derangements of carbohydrate and lipid metabolism in diabetic subjects.     

Dietary cinnamon supplementation and changes in systolic blood pressure in subjects with type 2 diabetes

Experimental and some clinical evidence suggests that ingestion of cinnamon may improve metabolic measures in individuals with diabetes; however, few human studies have been designed to examine this association as their primary objective. In this study adult subjects 30 years of age or older with type 2 diabetes were randomized to treatment with 1,200 mg/day cinnamon or matched placebo. Blood pressure, hemoglobin A1c, fasting blood glucose, lipid profile, physical examination, and blood and urine chemistry were measured at baseline and at the 12-week follow-up end-of-treatment visit. In total, 59 subjects (40.7% female; mean age, 63.05±10.85 years) were recruited. Systolic blood pressure (SBP) declined from baseline values by 3.4±11.4 mm Hg in the cinnamon group and increased by 1.9±10.2 mm Hg in the placebo group (P=.06). In repeated-measures analysis, a significant by-treatment difference over time was detected (P=.02). However, when baseline SBP was included in the model as a covariate, change from baseline SBP was no longer associated with treatment. Although cinnamon added to the diets of spontaneously hypertensive rats has been shown to decrease SBP in a dose-dependent manner, results of the present study in humans suggest that the by-treatment difference in change-from-baseline SBP was a function of regression to the mean rather than a treatment-associated change.     

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。     

Dietary carbohydrates, fiber, and breast cancer risk

Dietary fiber, fiber fractions, carbohydrate, glycemic index, and glycemic load were prospectively assessed five times over 18 years with a validated food frequency questionnaire in relation to breast cancer risk among 88,678 women (aged 34-59 years at baseline) in the Nurses' Health Study. Incident breast cancer occurred in 4,092 of these women between 1980 and 1998. The authors observed no material association between carbohydrate intake, glycemic index and glycemic load, total dietary fiber intake, and breast cancer risk. The relative risks for the highest versus the lowest quintile of intake were 0.97 (95% confidence interval (CI): 0.87, 1.08) for carbohydrates, 1.08 (95% CI: 0.97, 1.19) for glycemic index, 0.99 (95% CI: 0.89, 1.10) for glycemic load, and 0.98 (95% CI: 0.87, 1.11) for fiber. The relative risk comparing those in the highest 0.7% of fiber intake (>30 g/day) with those in the lowest 10% of fiber intake (< or =10 g/day) was 0.68 (95% CI: 0.43, 1.06). Analyses stratified by menopausal status and body mass index also showed no clear risk pattern. In this cohort of middle-aged women, no overall association was found for dietary carbohydrates, glycemic index and glycemic load, and breast cancer risk. This study also confirmed the lack of an overall association between intake of fiber and fiber types and breast cancer risk observed in other prospective studies.     

Dietary proteins and atherosclerosis

More than one hundred years ago the "protein hypothesis" of the pathogenesis of atherosclerosis and its association with cardiovascular disease was put forward on the basis of animal experiments; however, it has so far never been verified in humans. This theory was soon replaced by the "lipid hypothesis", which was confirmed in humans as of 1994. Epidemiological ecological studies in the 1960 s showed significant associations between dietary animal protein and mortality from cardiovascular disease. However, animal protein intake was also significantly correlated with saturated fatty acid and cholesterol intake. In the last decades two prospective cohort studies demonstrated a decreased cardiovascular risk in women during high- versus low-protein intake when adjusting for other dietary factors (e. g., saturated fats) and other cardiovascular risk factors. A direct cholesterol lowering effect of proteins has not been shown. Despite earlier research indicating that soy protein has cardioprotective effects as compared to other proteins, these observations have not been confirmed by randomized placebo-controlled trials. However, most experts recommend the consumption of foods rich in plant proteins as alternatives to meat and dairy products rich in saturated fat and containing cholesterol. There are no scientific arguments to increase the daily protein intake to more than 20 % of total energy intake as recommended by the guidelines, in order to improve cardiovascular health.     

Dietary non-digestible carbohydrates promote L-cell differentiation in the proximal colon of rats

One of the challenges in type 2 diabetes treatment is to ensure pancreas functionality with gut peptides such as glucagon-like peptide-1 (GLP-1). We have recently shown that the endogenous GLP-1 production is promoted by dietary non-digestible carbohydrates (oligofructose), the higher GLP-1 secretion could participate in the control of obesity and associated disorders. This experimental study was designed to highlight the mechanisms of endogenous increase of GLP-1 following non-digestible carbohydrate feeding. Male Wistar rats were fed a standard diet (70.4 g/100 g total carbohydrates; controls) or the same diet supplemented with oligofructose (10 g/100 g diet) for 4 weeks. GLP-1-producing L-cells of the colon were quantified by immunohistochemistry. GLP-1 was quantified by ELISA, and proglucagon, neurogenin 3 and NeuroD mRNA were measured in the colon by quantitative RT-PCR. The number of GLP-1-expressing cells was doubled in the proximal colon of oligofructose-treated rats, a phenomenon correlated with the increase in proglucagon mRNA and peptide content in the tissue. Moreover, oligofructose increased the number of enteroendocrine L-cells in the proximal colon by a mechanism involving up-regulation of two differentiation factors: neurogenin 3 and NeuroD. It is the first demonstration that nutrients fermented in the gut may promote L-cell differentiation in the proximal colon, a phenomenon contributing to a higher endogenous GLP-1 production. These results suggest a new mechanism by which dietary fibres may lower food intake and fat mass development.     

The difference in acute myocardial infarction pain between diabetic and non diabetic patients

The goal of this study was to compare the acute myocardial infarction (AMI) pain between diabetic and non diabetic patients. A sample of 80 AMI patients was divided in two groups, with and without diabetes mellitus (DM), being 29% diabetic and 71% non diabetic patients. The patients with DM said they had no pain (p<0.05) and gave lower scores for pain when compared with patients without DM. There was a significant difference between average scores for pain among diabetic and non diabetic patients (p<0.001). In conclusion, the diabetic patients presented no pain or diminished pain when compared with patients without diabetes.