Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study

BACKGROUND: The role of antioxidants in the pathogenesis of type 2 diabetes is uncertain. OBJECTIVE: We evaluated cross-sectional relations of dietary intakes and plasma concentrations of antioxidants with glucose metabolism in a high-risk population. DESIGN: The subjects were 81 male and 101 female first- and second-degree, nondiabetic relatives of patients with type 2 diabetes. Antioxidant intake data were based on 3-d food records. Subjects taking supplements containing beta-carotene or alpha-tocopherol were excluded. Plasma antioxidant concentrations were measured by HPLC. By using multiple linear regression analysis and adjusting for demographic, anthropometric, and lifestyle covariates, we studied whether dietary and plasma alpha- and beta-carotene, lycopene, and alpha- and gamma-tocopherol were related to fasting and 2-h concentrations of glucose and nonesterified fatty acids during an oral-glucose-tolerance test, to the homeostasis model assessment index of insulin resistance, and to measures of beta cell function (incremental 30-min serum insulin concentration during an oral-glucose-tolerance test and first-phase insulin secretion during an intravenous-glucose-tolerance test). RESULTS: In men, dietary carotenoids were inversely associated with fasting plasma glucose concentrations (P < 0.05), plasma beta-carotene concentrations were inversely associated with insulin resistance (P = 0.003), and dietary lycopene was directly related to baseline serum concentrations of nonesterified fatty acids (P = 0.034). In women, dietary alpha-tocopherol and plasma beta-carotene concentrations were inversely and directly associated, respectively, with fasting plasma glucose concentrations (P < 0.05). In both sexes, cholesterol-adjusted alpha-tocopherol concentrations were directly associated with 2-h plasma glucose concentrations (P < 0.05). CONCLUSION: The data suggest an advantageous association of carotenoids, which are markers of fruit and vegetable intake, with glucose metabolism in men at high risk of type 2 diabetes.     

Dietary Intake and Serum Level of Carotenoids in Lung Cancer Patients: A Case-Control Study

The aim of this study was to compare the dietary intake and serum levels of some selected carotenoids of lung cancer patients with healthy subjects. Thirty-five lung cancer patients and 33 healthy people were enrolled into this case-control study. Daily intake of nutrients was estimated using a semiquantitative food frequency questionnaire and a 3-day 24-h food recall questionnaire. The concentration of serum beta-carotene and lycopene were analyzed using a high performance liquid chromatography method. Case and control groups did not differ by the means of age, gender, smoking habits, weight, body mass index, mean daily energy intake, mean daily fat intake, and the percentage of daily energy provided by fat to total daily energy intake. The beta-carotene and lycopene intake of the case subjects was 96% and 195% greater than that of the control subjects. Daily intake of fruits and vegetables in the cancer group was higher than the control group. However, the serum concentration of 118% beta-carotene and 60% lycopene were higher in the control group. Despite a higher daily dietary intake of beta-carotene and lycopene by lung cancer patients, serum beta-carotene and lycopene concentrations were significantly lower than the group without cancer.     

Dietary carbohydrates and glycated proteins in the blood in non diabetic subjects

OBJECTIVES: To evaluate in non diabetic subjects the association of dietary carbohydrates with fructosamine, a measure of total non enzymatic glycated proteins in the blood associated with mortality, particularly from cardiovascular diseases. METHODS: A population sample of 252 subjects (137 men and 115 women, mean age 57) without diabetes and with fasting serum glucose <126 mg/100 mL, participated in the study. Diet and dietary glycemic load were measured with a validated food frequency questionnaire. Fructosamine was measured with a standard colorimetric method. Multiple linear regression was used to analyze the data. RESULTS: Serum fructosamine was positively associated with dietary glycemic load. Moreover, it was positively associated with intake of polyunsaturated fats and alcohol; and negatively with intake of monounsaturated fats, and with physical activity. CONCLUSION: The quality of carbohydrate and fat, as well as physical activity, may explain the variation of non enzymatic glycated serum proteins in non diabetic subjects.     

Plasma carotenoids and diabetic retinopathy

Diabetic retinopathy increases with duration of diabetes and may be associated with carotenoid status. Carotenoids alter the pro-oxidation/antioxidation balance, and circulating levels depend largely on dietary intake. Lower levels have been reported in diabetes and age-related macular degeneration; however, little is known of the relationship between carotenoids and diabetic complications. Consequently, the purpose of the present study was to evaluate the relationship between plasma carotenoids and diabetic retinopathy. We assessed the carotenoid-retinopathy relationship in 111 individuals with type 2 diabetes in a community-based, cross-sectional study. We photodocumented retinal status and used HPLC to measure plasma carotenoid concentrations. Data for clinical and demographic variables and risk factors for diabetic retinopathy were obtained from 24 h urine and fasting blood samples, and an interviewer-assisted lifestyle questionnaire. We found that the combined lycopene and lutein/zeaxanthin (non-pro-vitamin A (non-PVA) carotenoid) concentration when compared with the pro-vitamin A (PVA) carotenoids (alpha-carotene, beta-carotene and beta-cryptoxanthin) was significantly lower in the retinopathy than non-retinopathy group (OR 1.2 (95% CI 1.0, 1.4) v. 1.6 (95% CI 1.4, 1.7), respectively; P=0.009). A higher non-PVA:PVA ratio also predicted a lower risk of diabetic retinopathy, after adjustment for potential confounders (OR 0.33 (95% CI 0.12, 0.95); P=0.039). Finally, a higher concentration of PVA carotenoids was associated with greater odds of diabetic retinopathy, after adjustment for risk factors (P=0.049). We suggest synergies between carotenoids are implicated in diabetic retinopathy, independent of established risk factors. Importantly, our observations indicate dietary modulation of retinopathy risk may be possible by increasing intakes of lutein- and lycopene-rich foods.     

Zinc status and dietary quality of type 2 diabetic patients: implication of physical activity level

The purpose of this study was to analyze the relationships among zinc status, diet quality, glycemic control and self-rated physical activity level of type 2 diabetic patients. Dietary intakes for two non-consecutive days were measured by 24-hour recall method for seventy-six diabetic patients. Fasting blood glucose and HbA1c were measured for the assessment of glycemic control. We evaluated the extent of dietary adequacy by the percentage of subjects with a dietary intake of a nutrient less than the estimated average requirement(EAR), the dietary diversity score(DDS) and the dietary variety score(DVS). Zinc status was assessed from serum levels and urinary excretion. Dietary inadequacy was serious for five nutrients: riboflavin, calcium, thiamin, zinc and vitamin C. Dietary intakes from the meat, fish, and egg food groups and the milk food group were below the recommended level. We found that subjects with high levels of physical activities had significantly higher DVS and serum zinc levels compared to others (p<0.05). Fasting blood glucose levels and HbA1c were not significantly different across self-reported physical activity levels. Therefore, we suggest that maintaining physical activity at or above a moderate level is beneficial to improving dietary quality and zinc status.     

Relationship between serum carotenoids and hyperglycemia: a population-based cross-sectional study

The present study investigated the relationship between hyperglycemia and both serum carotenoids and intake of vegetables and fruits. Subjects with a history of diabetes mellitus (DM group, n = 133) or with hyperglycemia diagnosed using a 5.6% cutoff value for hemoglobin A1c (High HbA1c group, n = 151) were recruited from among inhabitants of a rural area in Hokkaido, Japan. Intake frequencies of vegetables and fruits were assessed using a questionnaire administered by public health nurses. Serum levels of carotenoids and retinol were measured using high-performance liquid chromatography. The relationships between high HbA1c or DM and both serum carotenoids and intake frequencies of vegetables and fruits were analyzed using logistic regression modeling for a case-control study; each case (High HbA1c or DM) was matched to two controls (healthy subjects without any history of disease) matched for sex and age (within 3 years). The odds ratio (OR) for high HbA1c was 0.49 (95% confidence interval: 0.29-0.85) on high intake frequency of carrot and pumpkin and the OR for DM was 1.21 (95% Cl: 0.79-1.84). No significant relationships were observed between high HbA1c and intake frequencies of other vegetables and fruits. The ORs on high serum levels of alpha- and beta-carotenes, lycopene, beta-cryptoxanthin and zeaxanthin and lutein were 0.38 (0.22-0.65), 0.35 (0.21-0.59), 0.57 (0.35-0.93), 0.35 (0.20-0.59), and 0.88 (0.54-1.46) for high HbA1c, respectively. In conclusion, intake of vegetables and fruits rich in carotenoids might be a protective factor against hyperglycemia.     

A network meta-analysis on the comparative efficacy of different dietary approaches on glycaemic control in patients with type 2 diabetes mellitus

The aim of the present study is to assess the comparative efficacy of different dietary approaches on glycaemic control in patients with type 2 diabetes mellitus using a systematic review of the literature. Electronic and hand searches were performed until July 2017. The inclusion criteria were defined as follows: (1) randomized trial with a dietary approach; (2) adults with type 2 diabetes mellitus; (3) outcome either HbA1c (%) and/or fasting glucose (mmol/l); (4) minimum intervention period of 12 weeks. For each outcome measure, random effects network meta-analysis was performed in order to determine the pooled effect of each intervention relative to each of the other interventions. A total of 56 trials comparing nine dietary approaches (low-fat, Vegetarian, Mediterranean, high-protein, moderate-carbohydrate, low-carbohydrate, control, low GI/GL, Palaeolithic) enrolling 4937 participants were included. For reducing HbA1c, the low-carbohydrate diet was ranked as the best dietary approach (SUCRA: 84%), followed by the Mediterranean diet (80%) and Palaeolithic diet (76%) compared to a control diet. For reducing fasting glucose, the Mediterranean diet (88%) was ranked as the best approach, followed by Palaeolithic diet (71%) and Vegetarian diet (63%). The network analysis also revealed that all dietary approaches significantly reduce HbA1c (? 0.82 to ? 0.47% reduction) and fasting glucose (? 1.61 to ? 1.00 mmol/l reduction) compared to a control diet. According to the network meta-analysis the Mediterranean diet is the most effective and efficacious dietary approach to improve glycaemic control in type 2 diabetes patients.     

Patient Characteristics do not Predict Poor Glycaemic Control in type 2 Diabetes Patients Treated in Primary Care

Many diabetic patients in general practice do not achieve good glycaemic control. The aim of this study was to assess which characteristics of type 2 diabetes patients treated in primary care predict poor glycaemic control (HbA1c > or = 7%). Data were collected from the medical records. 1641 patients were included who had mean HbA1c 7.1(SD 1.7)% , and 42% had HbA1c > or = 7%. On univariate analysis younger age; longer duration of diabetes; higher levels of blood glucose at diagnosis; most recent fasting blood glucose (FBG), total cholesterol, and triglyceride; higher body mass index (BMI); treatment with oral hypoglycaemic agents (OHA); treatment with insulin; more GP-visits for diabetes in the last year; and lower educational level were associated with poor control. Both in multiple linear regression and in multiple logistic regression higher levels of FBG (odds ratio (OR): = 1.6, 95% confidence interval (CI): 1.49, 1.70), treatment with OHA (OR: 2.1, 95% CI: 1.41, 3.04), treatment with insulin (OR: 7.2, 95% CI: 4.18, 12.52), lower educational level (OR: 1.26, 95% CI: 1.01, 1.56) were independently associated with poor levels of HbA1c. When FBG levels were excluded from the model, higher blood glucose at diagnosis, higher values for triglyceride and total cholesterol, and younger age predicted poor glycaemic control, but these variables explained only 15% of the variation in HbA1c. In conclusion prediction of poor glycaemic control from patient characteristics in diabetic patients in general practice is hardly possible. FBG appeared to be a strong predictor of HbA1c, which underlines the usefulness of this simple test in daily diabetes care. The worse metabolic control in those treated with either OHA or insulin suggests that current treatment regimes might be not sufficiently applied to reach the targets of care. Providers of diabetes care should be attentive to patients with lower educational level.     

Longitudinal associations between body mass index and serum carotenoids: the CARDIA study

Cross-sectional studies report an inverse association between BMI and serum carotenoid concentration. The present study examined the prospective association between BMI and the serum concentration of five carotenoids in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Serum carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, zeaxanthin/lutein, lycopene), BMI, dietary intake, physical activity and dietary supplement use were measured at years 0 and 7 in 3071 black and white male and female participants, who were either persistent smokers or non-smokers. Among non-smokers, year 0 BMI predicted year 7 serum carotenoid levels: obese subjects (BMI > or =30 kg/m2) had an average concentration of the sum of four carotenoids (alpha-carotene +beta-carotene + zeaxanthin/lutein+beta-cryptoxanthin) that was 22 % lower than the concentration among subjects with a BMI of less than 22 kg/m2. In contrast, the sum of carotenoids among smokers was only 6 % lower. Relationships between BMI and serum lycopene were weak. The change from year 0 to year 7 in serum carotenoids, except for lycopene, was inversely associated with the change in BMI among non-smokers but not among smokers. Parallel findings were observed for BMI and serum gamma-glutamyl transferase level. In summary, the observation that BMI predicted the evolution of serum carotenoids during a 7-year follow-up among young non-smoking adults is consistent with the hypothesis that carotenoids are decreased in protecting against oxidative stress generated by adipose tissue, while smokers maintain a minimal level of serum carotenoids independent of adiposity. The results for lycopene were, however, discordant from those of the other carotenoids.     

Glycaemic control in type II diabetic tube-fed patients with a new enteral formula low in carbohydrates and high in monounsaturated fatty acids: a randomised controlled trial

OBJECTIVES: To investigate the effects of long-term treatment with a new enteral formula low in carbohydrates and high in monounsaturated fatty acids (MUFAs), in comparison with a standard formula, on glycaemic control in tube-fed type II diabetic patients. DESIGN: Randomised, double-blind, controlled, multi-centre trial.Setting:Early rehabilitation centres, primary care and nursing facilities. SUBJECTS:A total of 78 patients with insulin-treated type II diabetes with HbA(1C) > or =7.0% and/or fasting blood glucose >6.66 mmol/l, who required enteral tube feeding due to neurological dysphagia. INTERVENTIONS: Patients received 113 kJ (27 kcal)/kg of body weight of either test feed or an isoenergetic, isonitrogenous enteral formula (control) for 12 weeks. Glycaemic control (total daily insulin dosage (IU), fasting blood glucose, and HbA(1C)) and gastrointestinal tolerance were monitored daily. RESULTS: After 12 weeks, median values for changes from baseline were as follows (test group vs control group, 'data as available' analysis): total daily IUs -6.0 vs 0.0 (P=0.0024), fasting blood glucose (mmol/l) -1.59 vs -0.08 (P=0.0068); HbA(1C) (%) -0.8 vs 0.0 (P=0.0016). Both formulas were tolerated comparably. CONCLUSIONS:This study indicates that in tube-fed insulin-treated type II diabetic patients, the new low-carbohydrate, high MUFA formula results in a more effective glycaemic control than the standard diet, while being comparable in safety.     

Quality of recording of data from patients with type 2 diabetes is not a valid indicator of quality of care. A cross-sectional study

BACKGROUND: The quality of recording of clinical data in diabetes care in general practices is very variable. It has been suggested that better recording leads to improved glycaemic control. OBJECTIVES: The purpose of this study was to assess the completeness of recording by GPs of data from type 2 diabetes patients; to compare recorded and missing data; and to investigate the association between completeness and glycaemic control. METHODS: A cross-sectional survey was carried out in 52 general practices. Medical records were scrutinized for the presence of 11 variables. Examining patients through an active approach completed incomplete records. We compared recorded and unrecorded items. Completeness of recording was determined at both patient and practice levels. RESULTS: Fifty-two general practices with 1641 type 2 diabetes patients cared for by the GP participated. The frequency of absence of any particular item ranged from 20 to 70%. Weight, systolic blood pressure and HbA(1c) were slightly lower in patients with those items missing on their files, and more such patients were non-smokers (P < 0.05). The percentage of patients with unrecorded variables that exceeded target values ranged from 39 to 75. Neither at practice level nor at patient level was any association between the completeness of the data recording and HbA(1c) found. CONCLUSION: Records often were incomplete, which hampers a systematic approach to care of diabetic patients. However, the lack of association between completeness of data recording and control of glycaemia indicates that improved recording is not a valid indicator of good quality of care.     

Towards understanding of glycaemic index and glycaemic load in habitual diet: associations with measures of glycaemia in the Insulin Resistance Atherosclerosis Study

Epidemiologic studies have applied the glycaemic index (GI) and glycaemic load (GL) to assessments of usual dietary intake. Results have been inconsistent particularly for the association of GI or GL with diabetes incidence. We aimed to advance understanding of the GI and GL as applied to food frequency questionnaires (FFQ) by evaluating GI and GL in relation to plasma measures of glycaemia. Included were 1255 adults at a baseline examination (1994-6) and 813 who returned for the 5-year follow-up examination. Usual diet, at both examinations, was assessed by a validated FFQ. GI and GL were evaluated in relation to average fasting glucose (two measures at each examination) and 2 h post-75 g glucose load plasma glucose (baseline and follow-up), and glycated haemoglobin (A1c; follow-up only); using generalized linear models. Correlation coefficients (r) for GI and GL related to measures of glycaemia, adjusted for total energy intake, ranged from -0.004 to 0.04 (all NS) for both examinations. Adjustment for potential confounders, for fasting glucose in models for 2 h glucose (to model incremental glucose) and for average fasting glucose in models for A1c (to account, in part, for overnight endogenous glucose production) also did not materially alter findings, nor did inclusion of data from both examinations together in linear mixed models. The present results call into question the utility of GI and GL to reflect glycaemic response to food adequately, when used in the context of usual diet. Further work is needed to quantify usual dietary exposures relative to glucose excursion and associated chronic glycaemia and other metabolic parameters.     

Hyperglycemia and Carotenoid Intake Are Associated with Serum Carotenoids in Youth with Type 1 Diabetes

BackgroundSerum carotenoids are commonly used as biomarkers of fruit and vegetable (F/V) intake in the general population. Although hyperglycemia induces oxidative stress, it is unknown whether this pathway is associated with lower serum carotenoid concentrations in individuals with type 1 diabetes. Consequently, the utility of serum carotenoids as markers of F/V intake in individuals with type 1 diabetes is unclear.ObjectiveThe study objectives were: 1) to investigate the relationship of glycemic control, oxidative stress, dietary carotenoid and F/V intake with serum carotenoid concentrations in youth with type 1 diabetes and 2) to determine whether glycemic control or oxidative stress moderates the association of carotenoid and F/V intake with serum carotenoids.DesignThe study was a secondary analysis of baseline data from youth with type 1 diabetes. Blood samples were drawn from youth with type 1 diabetes to assess carotenoids and markers of glycemic control (glycated hemoglobin and 1,5-anhydroglucitol); urine samples were used to assess oxidative stress (8-iso-prostaglandin F_2α); and 3-day diet records completed by families were used to determine F/V and carotenoid intake.Participants/settingThe study participants were youth with type 1 diabetes (n=136; age range: 8 to 16.9 years; diabetes duration ≥1 year; glycated hemoglobin: 5.8% to 11.9%) enrolled in a nutrition intervention trial from 2010 to 2013 at a tertiary diabetes center in Boston, MA.Main outcome measuresSerum carotenoids (total carotenoids and α-carotene, β-carotene, lycopene, β-cryptoxanthin, and lutein+zeaxanthin).Statistical analysisRegression analyses were used to estimate the association of glycemic control, oxidative stress, F/V and carotenoid intake with serum carotenoids, as well as the role of glycemic control and oxidative stress in moderating diet-serum carotenoid associations.ResultsGreater F/V intake (β=0.35, P<0.001) and carotenoid intake (β=0.28, P<0.01) were associated with higher total serum carotenoids, and no moderation by glycemic control or oxidative stress was observed. Greater hyperglycemia, as indicated by lower 1,5-anhydroglucitol (β=0.27, P<0.01), was related to lower serum carotenoids; however, glycated hemoglobin was not associated with serum carotenoids. 8-Iso-prostaglandin F2α was not associated with glycemic control or serum carotenoids.ConclusionsFindings support the validity of serum carotenoids as markers of F/V and carotenoid intake in youth with type 1 diabetes.     

Serum and tissue lycopene and biomarkers of oxidation in prostate cancer patients: a case-control study.

Dietary intake of tomatoes and tomato products containing lycopene, an antioxidant carotenoid, has been shown in recent studies to reduce the risk of cancer. This study was conducted to investigate the serum and prostate tissue lycopene and other major carotenoid concentrations in cancer patients and their controls. Serum lipid and protein oxidation was also measured. Twelve prostate cancer patients and 12 age-matched subjects were used in the study. Significantly lower serum and tissue lycopene levels (44%, p = 0.04; 78%, p = 0.050, respectively) were observed in the cancer patients than in their controls. Serum and tissue beta-carotene and other major carotenoids did not differ between the two groups (p = 0.395 and p = 0.280, respectively). Although there was no difference (p = 0.760) in serum lipid peroxidation between cancer patients and their controls (7.09 +/- 0.74 and 6.81 +/- 0.56 mumol/l, respectively), serum protein thiol levels were significantly lower among the cancer patients (p = 0.026). This study demonstrates that the status of lycopene but not other carotenoids in prostate cancer patients is different from controls. The role of dietary lycopene in preventing oxidative damage of biomolecules and thereby reducing the risk of prostate cancer needs to be evaluated in future studies.     

Levels of fasting blood glucose and serum fructosamine for monitoring of glucose control in patients with non-insulin-dependent diabetes mellitus

The predictive values of fasting blood glucose and serum fructosamine for monitoring long-term diabetic control were investigated in 98 non-insulin dependent diabetic patients. The HbAlc percentage was taken as standard in this study. Despite a significant correlation, the predictive values of the parameters studied for an acceptable HbAlc-value appeared to be low (37% and 44% respectively), possibly due to differences in periods of time in which these parameters can change during variable metabolic control. In addition, the serum fructosamine value may vary due to variations in serum albumin and lipid content. It is concluded that the fasting blood glucose and serum fructosamine values cannot replace HbAlc measurement for monitoring diabetic control, but are supplementary for assessment of this control over short- and long-term periods of time.     

Carotenoid status among preschool children with vitamin A deficiency in the Republic of the Marshall Islands

Although carotenoids are known to be important dietary sources of vitamin A, there have been few epidemiological studies that have characterized the serum concentrations of major dietary carotenoids among preschool children with vitamin A deficiency. We conducted a population-based, cross-sectional study of serum pro-vitamin A carotenoids (alpha -carotene, beta-carotene, beta-cryptoxanthin), non-provitamin A carotenoids (lutein/zeaxanthin, and lycopene), and retinol among 278 children, aged 1-5 y, in the Republic of the Marshall Islands. Vitamin A deficiency was defined as serum retinol <0.70 micromol/L. Geometric mean serum concentrations of carotenoids among children with and without vitamin A deficiency were 0.003 vs 0.006 micromol/L for alpha-carotene (P = 0.0017), 0.011 vs 0.023 micromol/L for beta-carotene (P <0.0001), 0.023 vs 0.034 micromol/L for beta-cryptoxanthin (P = 0.0075), 0.007 vs 0.012 micromol/L for lycopene (P = 0.037), 0.044 vs 0.052 micromol/L for lutein/zeaxanthin (P = 0.2), and 0.045 vs 0.074 micromol/L for total provitamin A carotenoids (P <0.0001) respectively. In a multivariate analysis adjusting for sex, age (Odds Ratio [O.R.] 1.44, 95% confidence interval [C.I.] 1.16-1.78), and serum provitamin A carotenoids (O.R. 0.49, 95% C.I. 0.34-0.71) were associated with vitamin A deficiency, but serum non-provitamin A carotenoids were not associated with vitamin A deficiency (O.R. 0.93, 95% C.I. 0.67-1.28). Preschool children with vitamin A deficiency in the Republic of the Marshall Islands have extremely low serum concentrations of provitamin A carotenoids and interventions are needed to improve the dietary intake of provitamin A carotenoids among Marshallese children.     

Effects of pinitol isolated from soybeans on glycaemic control and cardiovascular risk factors in Korean patients with type II diabetes mellitus: a randomized controlled study

OBJECTIVE: To assess the effects of soybean-derived pinitol on glycaemic control and cardiovascular risk factors in Korean patients with type II diabetes mellitus. DESIGN: Randomized, double-blind, placebo-controlled, parallel-group trial. SETTING: Pusan Paik Hospital, Pusan, Republic of Korea. INTERVENTIONS: A total of 30 patients with type II diabetes received an oral dose of 600 mg soybean-derived pinitol or placebo twice daily for 13 weeks. RESULTS: Pinitol significantly decreased mean fasting plasma glucose, insulin, fructosamine, HbA1c, and the homeostatic model assessment insulin resistance index (HOMA-IR, P<0.001). Pinitol significantly decreased total cholesterol, LDL-cholesterol, the LDL/HDL-cholesterol ratio, and systolic and diastolic blood pressure and increased HDL-cholesterol (P<0.05). CONCLUSIONS: These data suggest that soybean-derived pinitol may be beneficial in reducing cardiovascular risk in Korean type II diabetes.     

Effects of two different glibenclamide dose-strengths in the fixed combination with metformin in patients with poorly controlled T2DM: a double blind, prospective, randomised, cross-over clinical trial

A double-blind, prospective, randomised, cross-over clinical trial was performed comparing a glibenclamide (G) 5.0 mg/metformin (M) 400 mg combination with a G 2.5 mg/M 400 mg formulation to evaluate whether a higher dose of glibenclamide was able to improve glycaemia in poorly controlled Type 2 diabetic patients. One hundred and ninety-eight patients with poorly controlled Type 2 diabetes mellitus were randomised to receive one of the two trial drugs for a first 3-month period, and were then assigned to the alternative combination for further 3 months. The starting dose (2 tablets/day, 30 min before breakfast and dinner) was to be up-titrated to 3 tablets/day when required. A standard dietary regimen was kept constant for the total trial duration. Fasting plasma glucose, HbA1c, C-peptide, insulin and lactate levels, haematology and blood chemistry were measured at the start/end of each cycle. Patients' self-assessment of the glycaemic profile (at fasting and 2 hr after the main meals) was performed weekly. Patients were constantly monitored for adverse events and episodes of hypoglycaemia, and all events were recorded. Decrease of mean fasting glucose levels measured in the first cycle was more pronounced in the group treated with G 5.0 mg/M 400 (p<0.01) compared to baseline, although the difference was not significant--no changes were observed in the second 3-month period. Results of patients' self-assessment of the glycaemic profile in the overall 6-month period show that the two trial drugs produced similar effects on fasting glucose, but the decrease of post-prandial glycaemic levels was markedly higher with G 5 mg/M 400 mg than with G 2.5 mg/M 400 mg at both main meals. A similar significant decrease (p<0.01) of HbA1c was observed in both sequence groups at the end of the first 3-month treatment period, and mean levels remained unchanged at 6 months. Drug-related adverse events were observed in 2 patients during treatment with G 2.5 mg/M 400 mg and in 5 with G 5 mg/M 400 mg, while 14 and 22 episodes of hypoglycaemia occurred with the two trial drugs, respectively (p=NS between treatments). Metformin-induced increases of lactate levels were similar in the two sequence groups. No differences between groups were found either in the number of up-titrated patients or in all the other laboratory parameters. In conclusion, the new combination containing 5-mg glibenclamide produced a greater improvement in post-prandial glycaemic control compared with the standard fixed doses, and resulted equally safe and well tolerated.     

Factors Associated with Consumption of Diabetic Diet among Type 2 Diabetic Subjects from Ahmedabad,Western India

This cross-sectional study assessed the current situation of and factors associated with consumption of diabetic diet among 399 type 2 diabetes mellitus (T2DM) subjects from Ahmedabad, Western India. The study was performed with diagnosed (at least one year old) diabetic subjects who attended the Department of Diabetology, All India Institute of Diabetes and Research and Yash Diabetes Specialties Centre (Swasthya Hospital), Ahmedabad during July 2010–November 2010. The subjects completed an interviewer-administered questionnaire. The questionnaire included variables, such as sociodemographic factors, family history of diabetes, behavioural profile, risk profile (glycaemic status, hypertension, and obesity), and diet-related history (consumption of diabetic diet, consumption of low fat/skimmed milk, method of cooking, and sources for diet advice). Blood pressure, body mass index, glycosylated haemoglobin (HbA1c) level, and fasting lipid profile were measured. All analyses including multivariate logistic regression were conducted using SPSS, version 11.5. In total, 399 T2DM subjects (65% male, 35% female) with mean age of 53.16±7.95 years were studied. Although 73% of T2DM subjects were consuming diabetic diet, the good glycaemic control (HbA1c level <7%) was achieved only in 35% of the subjects. The majority (75%) of the subjects had a positive family history of diabetes, and 52% were obese. In 77%, the main source of dietary advice was doctor. In 36%, the main methods of cooking were: boiling and roasting. The final multivariate model showed that visit to dietician, level of education, intake of low fat, and family history of diabetes were independent predictors for diabetic diet consumption among T2DM subjects. However, longitudinal and cohort studies are required to establish the association between consumption of diabetic diet and glycaemic control.Key words: Cross-sectional study, Diet, Glycaemic control, Glycosylated haemoglobin, Obesity, Type 2 diabetes mellitus, India     

Prostatic levels of tocopherols, carotenoids, and retinol in relation to plasma levels and self-reported usual dietary intake

This study evaluated how prostatic levels of antioxidants relate to plasma levels and self-reported usual dietary intake. Definition of these relations may aid in interpreting studies of antioxidant exposure and prostate cancer risk. Between July 1996 and April 1997, plasma and prostatic tissue levels of tocopherols, carotenoids, and retinol were measured in 47 men undergoing radical prostatectomy or transurethral prostatectomy at Loyola University Medical Center, Maywood, Illinois, and an affiliate hospital. Dietary intake was measured by using a 122-item version of the Block Health Habits and History Questionnaire, and correlations were assessed with Pearson's coefficients. Prostatic levels of tocopherols and carotenoids (but not retinol) were significantly correlated with plasma levels (r= 0.31-0.56, p < 0.05-0.0001); the strongest correlations were associated with lycopene, beta-carotene, and gamma-tocopherol (0.56, 0.54, and 0.52, respectively; p < 0.0001). Relative concentrations of tocopherols and carotenoids in prostate tissue were proportionate to those in plasma. No correlation between prostatic levels and reported dietary intake was observed (r = -0.09 to 0.16, p < not significant). Adjustment for energy intake, body mass index, and serum lipids did not impact these relations. These results suggest that plasma levels of tocopherols and carotenoids better reflect prostatic exposure than self-reported usual dietary intake.