The effects of sesame, canola, and sesame-canola oils on cardiometabolic markers in patients with type 2 diabetes: a triple-blind three-way randomized crossover clinical trial.

AIMS: To compare the effects of replacing regular dietary oils intake with sesame (SO), canola (CO), and sesame-canola (SCO) oils (a novel blend), on cardiometabolic markers in adults with type 2 diabetes mellitus (T2DM), in a triple-blind, three-way, randomized, crossover clinical trial. METHODS: Participants were assigned to receive SO, CO, and SCO in three 9-week phases (4 weeks apart). Cardiometabolic makers (serum lipids, Apolipoprotein, cardiovascular risk scores, kidney markers, and blood pressure) were considered at the beginning and the end of intervention phases. RESULTS: Ninety-two, ninety-five, and ninety-five participants completed the SO, SCO, and CO periods, respectively. After CO consumption, serum Apo A-1 concentrations were significantly higher compared with the SCO period in the whole population (p < 0.05). A considerable reduction in visceral adiposity index values was seen in the CO compared with the SO period in males (p < 0.05). Serum high-density lipoprotein concentration was also significantly higher after the SO intake compared with SCO in females (p < 0.05). The between-period analysis showed a substantial reduction in diastolic blood pressure in the SCO period compared with the CO and SO periods and lower systolic blood pressure after SCO versus CO intake in males (p < 0.05). CONCLUSIONS: Canola oil might protect CVD through improving Apo A-1 levels in patients with T2DM (particularly in females) and visceral adiposity index in male patients. However, the blend oil might beneficially affect blood pressure in men. Future sex-specific studies might warrant the current findings. REGISTRY OF CLINICAL TRIALS: This trial was registered in the Iranian Registry of Clinical Trials (IRCT, registration ID: IRCT2016091312571N6).

Validity and Reproducibility of a Semiquantitative Multiple-Choice Food Frequency Questionnaire in Iranian Adults.

Previous multiple-choice food-based food frequency questionnaires (FFQs) were not validated against weighed dietary records (WDRs) in Iran. This study investigated the validity and reproducibility of a multiple-choice semi-quantitative food frequency questionnaire (SQ-FFQ) in adults living in central Iran. Patients with diabetes and their spouses were asked to complete 3 SQ-FFQs by interview, and nine 3-day WDRs, over 9 months. They provided 2 blood samples to assess serum calcium, magnesium, zinc, and vitamin C levels. The Pearson and intraclass correlation coefficients were calculated to assess reproducibility and validity. The degree of misclassification was explored using a contingency table of quartiles which compare the information between third FFQ and WDRs. The method of triads was incorporated to assess validity coefficients between estimated intakes using third FFQ, WDRs, and biochemical markers and assumed true intakes. A total of 180 participants aged 48.9 ± 8.4 years completed the study. Compared to WDRs, FFQs overestimated all nutrient intakes except for iron. The median intraclass correlation between FFQs was 0.56. The median de-attenuated, age, sex, and education adjusted partial correlation coefficients for validity were 0.17 and 0.26 for FFQ1-WDRs and FFQ3-WDRs, respectively. The FFQ3 validity coefficients for vitamin C, calcium, magnesium, and zinc were 0.13, 0.62, 0.89, and 0.66, respectively, using the triads method. The median exact agreement and complete disagreement between FFQ3 and WDRs were 33% and 6%, respectively. The SQ-FFQ seems to be an acceptable tool to assess the long-term dietary intake for future large-scale studies in this population.

The effect of sesame, canola, and sesame-canola oils on cardiometabolic risk factors in overweight adults: a three-way randomized triple-blind crossover clinical trial.

Limited data exist on the cardiometabolic effects of sesame oil compared with canola oil. In the present study, 77 overweight adults were randomized to replace their regularly consumed oils with canola (CO), sesame (SO), and sesame-canola oils (SCO, 40% SO, and 60% CO) in three 9-week phases. Blood pressure, visceral adiposity index, serum apo-proteins (APOs) and lipid profile, glycemic control markers, kidney markers, liver enzymes, and cardiovascular disease risk scores were assessed at baseline and endline. After adjustment for confounders, SO significantly reduced serum alkaline aminotransferase (ALT) compared to CO (p ≤ 0.05) in all participants, increased serum urea compared to SCO in males, and decreased serum alkaline phosphatase compared to other oils in males, and improved serum high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) compared to SCO, and eGFR compared with CO in females (p ≤ 0.05). Canola oil significantly improved serum Apo A1 and APO B/A ratio compared with SO, in males (p ≤ 0.05). Sesame-canola oil significantly reduced serum urea compared to other oils in all participants (p ≤ 0.05). Sesame oil and SCO might beneficially affect serum ALT and urea, respectively. Intervention oils might have different cardiometabolic effects in each gender. Further studies are needed to confirm our results (Trial registration code: IRCT2016091312571N6).

Effects of sesame, canola and sesame-canola oils on body weight and composition in adults with type 2 diabetes mellitus: a randomized, triple-blind, cross-over clinical trial.

BACKGROUND: Recent investigations have proposed that sesame and canola oils might affect body fat distribution. The present study aimed to examine the effects of sesame, canola and sesame-canola (a blend of sesame and canola oils) oils on body weight and composition in adults with type 2 diabetes mellitus in the context of a randomized, triple-blind, three-way, cross-over clinical trial. RESULTS: Eligible participants were randomized to replace their regular dietary oil with sesame oil (SO), canola oil (CO) and sesame-canola oil (SCO) (with 40% SO and 60% CO). Treatment periods lasted 9 weeks and were separated by 4-week wash-out periods. Body weight and composition were measured at the beginning, in the middle and at the end of each intervention phase. In total, 93 participants completed the study. After adjustment for confounders, within-period changes were observed following SO and CO intake for body weight (0.34 ± 0.16 kg and 0.33 ± 0.17 kg) and visceral fat (0.13 ± 0.06% and 0.13 ± 0.05%, P < 0.05), respectively. Body mass index was increased within SO intake (0.13 ± 0.05 kg m-2 , P = 0.031). All of the treatment oils resulted in reduced waist circumference and index of central obesity (P < 0.05). A significant difference in change values was observed for visceral fat between SCO (-0.14 ± 0.07%) and SO (0.12 ± 0.08%) treatment periods in females (P = 0.02). CONCLUSION: Sesame and canola oils might lead to a modest favorable body fat redistribution by reducing central adiposity, particularly in females; however, the changes were of little clinical importance. © 2021 Society of Chemical Industry.

Meta-analysis of vitamin D supplementation and hemoglobin concentration: methodological faults obscure the interpretation of the data.

We read the review by Arabi et al. with great interest which tried to examine the effects of vitamin D supplementation on hemoglobin concentration. It seems that the article suffers from fundamental methodological issues and the conclusions are likely to be erroneous. In this regard, we would like to ask the authors to address the mentioned limitations and to update the analysis in order to provide robust and trustful results. We are concerned that such meta-analyses may lead to the biased findings and conclusions.

Canola oil compared with sesame and sesame-canola oil on glycaemic control and liver function in patients with type 2 diabetes: A three-way randomized triple-blind cross-over trial.

BACKGROUND: This study aimed to compare the effects of sesame (SO), canola (CO), and sesame-canola (SCO: a blend) oils on glycaemic control markers and liver function enzymes in adults with type 2 diabetes. METHODS: In this randomized, triple-blind, three-way, cross-over clinical trial, participants replaced their usual oil with the intervention oils for 9 weeks. Serum fasting blood sugar, fasting serum insulin (FSI), insulin resistance (HOMA2-IR), beta-cell function (HOMA2-%B), insulin sensitivity (HOMA2-%S), quantitative insulin sensitivity check index (QUICKI), as well as serum liver function enzymes were measured at baseline and end of intervention periods. RESULTS: Ninety-two participants completed all treatment periods. After adjusting for confounders, all treatment oils resulted in significant improvements in FSI and HOMA2-%S (p < 0.05). SO and SCO led to favourable changes in HOMA2-IR and QUICKI (p < 0.05). Following CO and SCO, there was a significant decrease in HOMA2-%B (p < 0.05). The sex-stratified analysis revealed that FSI and HOMA2-IR were decreased after SO compared to CO in males (p = 0.024). Serum gamma-glutamyltransferase (GGT) was significantly lower following SO compared to CO in females (p = 0.02), however, the difference in change values was not significant (p = 0.058). CONCLUSIONS: SO consumption appears to improve glycaemic control markers in males and serum GGT in females compared with CO in patients with type 2 diabetes (registration code: IRCT2016091312571N6).

The effect of canola, sesame and sesame-canola oils on body fat and composition in adults: a triple-blind, three-way randomised cross-over clinical trial.

The present study aimed to examine the effect of replacing edible oils with sesame oil (SO), canola oil (CO) and sesame-canola oil (SCO) on body weight and composition in adults. Adults without any chronic diseases (n = 77) were entered a 4-week run-in period and then were randomised to receive SO, CO and SCO for their household use in 9-week intervention periods (separated by 4-week washout intervals). Anthropometric measurements, as well as body composition markers, were assessed at baseline, middle and after each intervention period. In total, 73 participants completed the study. Although significant time effects were seen for waist and hip circumference, waist-to-hip ratio, central obesity index, body adiposity index, muscle mass and body fat percent (ptime<.05), the treatment and treatment × time effects were not significant (p>.05). The present clinical trial revealed that CO, SO and SCO might not differently affect body fat and composition. Trial registration code: IRCT2016091312571N6 (http://en.irct.ir/trial/12622).

The combined effects of cholesteryl ester transfer protein (CETP) TaqIB gene polymorphism and canola, sesame and sesame-canola oils consumption on metabolic response in patients with diabetes and healthy people.

Introduction: Cholesteryl ester transfer protein (CETP) is a key regulating enzyme in the lipid metabolism pathway, and its gene polymorphism may be a candidate for modulating the metabolic responses to dietary intervention. We thus examined whether the effects of the CETP TaqIB polymorphism on metabolic profiles were modified by dietary plant oils. Methods: This is a retrospective analysis of data collected during a randomized triple-blind cross over trial. A total of 95 patients with type 2 diabetes and 73 non-diabetes individuals completed a 9-weekof the intake of sesame, canola and sesame-canola oils. Blood samples were collected at the beginning and at the end of each intervention period for biochemical analysis. Genotyping was done using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Results: In diabetes patients, B1B1 homozygotes of the CETP TaqIB polymorphism compared with B2 carriers (B1B2 + B2B2) had significantly lower diastolic blood pressure, apoB and apoB: apoA-1,and higher Lp(a) after the intake of sesame-canola oil, as well as lower insulin and HOMA-IR after the intake of sesame oil. There was also a significant effect of genotype on adjusted changes of apoB, apoB: apoA-1, insulin, HOMA-IR and QUICKI. A significant genotype-dietary oils combined effects were observed for diastolic blood pressure, and LDL: HDL, TC: HDL and TG: HDL ratios in diabetes patients. No independent or combined effects of dietary oils and genotypes on outcomes were found in healthy people. Conclusion: There was a modulatory effect of the CETP TaqIB polymorphism on some metabolic traits in response to plant oils in patients with diabetes. Taken together, the intake of sesame-canola and canola oils showed more favorable effects in diabetes patients with B1B1 genotype. Future investigations are needed to confirm these results.

Association of rs670 variant of APOA-1 gene with cardiometabolic markers after consuming sesame, canola and sesame-canola oils in adults with and without type 2 diabetes mellitus.

BACKGROUND & AIMS: The inter-individual variations of the metabolic markers in response to dietary interventions may be mediated by genetic factors. We examined whether the type of dietary oils can modulate the effects of -75G/A polymorphism in APOA-1 gene on cardiometabolic markers. METHODS: This study was a randomized, triple-blind, cross-over clinical trial. Participants with and without type 2 diabetes were randomly assigned to replace their regular oil with sesame oil, canola oil and sesame-canola oil for 9 weeks. Genotyping was conducted using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: Ninety-five diabetes patients and 73 healthy individuals completed the study protocol. In patients with type 2 diabetes, the A allele carriers experienced greater decrease in systolic blood pressure compared with GG homozygotes following sesame-canola oil intake. Serum levels of HDL-C and TG: HDL ratio was increased and decreased following canola oil intake in patients carrying the A allele rather than non-A allele carriers, respectively. More reductions for risk of cardiovascular diseases and mortality, except risk of stroke were found in the A allele carriers compared with GG homozygotes after intakes of canola and sesame-canola oils, but not sesame oil. There was also a significant genotype effect as well as genotype-dietary oil interactions on cardiovascular risk scores. In healthy individuals, a considerable decrease in visceral fat was accompanied by a significant increase in HDL-C levels in the A allele carriers compared with non-A allele carriers after sesame oil intake. CONCLUSION: Patients with diabetes carrying the A allele might benefit from canola and sesame-canola oils intakes, and healthy A allele carriers from sesame and sesame-canola oils intakes as well. Future clinical trials are recommended to warrant current findings.

The healthy Nordic diet for blood glucose control: a systematic review and meta-analysis of randomized controlled clinical trials.

AIMS: Investigations on the possible effect of the Nordic diet (ND) on the glycemic control and the risk of diabetes have led to inconsistent results. The present study tried to determine the effect of the ND on the markers of blood glucose control using a systematic review and meta-analysis of randomized controlled clinical trials (RCTs). METHODS: Predefined keywords were used to search PubMed, ISI Web of Science, Scopus and Google Scholar up to April 2019. The random effects model was used to compute the overall estimates. RESULTS: In total, six RCTs with 618 participants (6-26 weeks of follow-up period) were included in the present study. The meta-analysis revealed that the ND might not have a considerable effect on fasting blood glucose levels [weighted mean difference (WMD) = -0.05 mmol/l, 95% CI - 0.13, 0.01, P = 0.112]. In contrast, the analyses showed that the ND significantly reduces serum insulin concentrations (WMD = -1.12 mU/l, 95% CI - 1.84, - 0.39, P = 0.002) and the homeostasis model assessment for insulin resistance (HOMA-IR) (WMD = - 0.34, 95% CI - 0.53, - 0.14, P = 0.001) compared to control diets. The effect on serum insulin levels was sensitive to one of the included studies. This dietary pattern did not significantly affect 2-h post-prandial blood glucose and Matsuda index. CONCLUSIONS: Adherence to the ND might improve serum insulin and HOMA-IR levels; however, this effect was not confirmed for other markers of blood glucose control. Future well-designed and long-term clinical trials are highly recommended.

The effect of canola oil compared with sesame and sesame-canola oil on cardio-metabolic biomarkers in patients with type 2 diabetes: Design and research protocol of a randomized, triple-blind, three-way, crossover clinical trial.

BACKGROUND: Both canola and sesame oils consumption have been associated with favorable effects on cardio-metabolic biomarkers. However, to the best of our knowledge, no study has compared their effects on cardiovascular risk factors. The present study aimed to assess the effect of canola, sesame, and sesame-canola oils consumption on cardio-metabolic biomarkers in patients with type 2 diabetes mellitus (T2DM). METHODS: This study was a randomized, triple-blind, three-way, crossover clinical trial. The study participants included 102 individuals with T2DM. Their spouses were also included in the study. The participants were entered into a 4-week run-in period. After that, their regular dietary oil was replaced with canola, sesame, or sesame-canola oils (a blend of sesame and canola oils) in three 9-week phases, which were separated by two 4-week washout periods (sunflower oil was consumed during the run-in and the washout periods). Dietary, physical activity, blood pressure, and anthropometric measurements were assessed at the beginning, in the middle (week 4-5), and at the end of each treatment phase. Blood samples were taken at the beginning and at the end of each phase. Serum, plasma, buffy coat, and whole blood samples were extracted and kept at -80 ºC for further analysis. Serum fasting blood sugar (FBS), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were selected as the primary outcomes. RESULTS: 102 participants with T2DM were randomly assigned to one of the 6 rolling methods. Through them, 93 individuals (91.2%) completely participated in all phases. CONCLUSION: The present study will provide an exceptional opportunity to examine the effect of canola, sesame, and sesame-canola oil on cardio-metabolic markers in adults with and without T2DM. This trial will also provide a good medium for the investigation of gene-dietary oils interaction in the future.