Effects of green coffee aqueous extract supplementation on glycemic indices, lipid profile, CRP, and malondialdehyde in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial

Background/objectivesStudies have reported the health benefits of green coffee extract (GCE) in experimental models. In the current study, we aimed to determine whether supplementation with GCE improves glycemic indices, inflammation, and oxidative stress in patients with type 2 diabetes (T2D).Methods and study designThis randomized, double-blind, placebo-controlled trial included 44 patients (26 male and 18 female) with T2D and overweight/obesity. After blocked randomization, patients received either capsules containing 400 mg GCE twice per day (n = 22) or a placebo (n = 22) and were followed for 10 weeks. In this study, glycemic indices, lipid profiles, anthropometric examinations, blood pressure, high-sensitivity C-reactive protein (hs-CRP), and malondialdehyde (MDA) were measured twice; at baseline and at the end of the study.ResultsAfter 10 weeks of supplementation, GCE supplementation significantly reduced body weight (p = 0.04) and body mass index (BMI) (p = 0.03) compared to the placebo. The intention-to-treat (ITT) analysis indicated patients in the GCE group had a lower fasting blood glucose (FBG) concentration compared to the placebo group; however, this decreasing was marginally significant (8.48 ± 8.41 vs. 1.70 ± 5.82 mg/dL, p = 0.05). There was no significant difference in insulin levels and HOMA-IR between the groups. At the end of the study, significant changes in systolic blood pressure (SBP) (p = 0.01), triglyceride (TG) level (p = 0.02), high-density lipoprotein (HDL) (p = 0.001), and TG-to-HDL ratio (p = 0.001) were found between the intervention and placebo groups. Our trial indicated GCE supplementation had no effect on diastolic blood pressure (DBP), low-density lipoprotein (LDL), or total cholesterol. During the supplementation period, the hs-CRP level significantly decreased in the GCE group compared to the placebo group (p = 0.02). No significant changes were observed in the MDA level between the two groups at the end of the study (p = 0.54).ConclusionOur findings showed beneficial effects of GCE on SBP, TG, hs-CRP, and HDL levels in patients with T2D and overweight/obesity over a 10-week period of supplementation.Clinical trial registration:https://en.irct.ir/trial/48549, identifier [IRCT20090203001640N18]

A Prospective Study of Different Types of Dietary Fiber and Risk of Cardiovascular Disease: Tehran Lipid and Glucose Study

Background and aim: This study was designed to examine the hypothesis that dietary of intake different types of fiber could modify the risk of cardiovascular disease (CVD) in a large prospective cohort among Iranian adults. Methods: In 2006–2008, we used a validated food frequency questionnaire to assess dietary fiber intake among 2295 health professionals with no previous history of heart disease. Subjects were subsequently followed until 2012 for incidence of CVD events. Multivariate Cox proportional hazard regression models, adjusted for potential confounders were used to estimate the risk of CVD across tertiles of total dietary fiber and different types of fiber. Linear regression models were also used to indicate the association of dietary fiber intakes with changes of cardiovascular risk factors during the follow-up. Results: Mean age of participants (42.8% men) was 38.2 ± 13.4, at baseline. Mean (SD) dietary intake of total fiber was 23.4 (8.9) g/day. After adjustment for cardiovascular risk score and dietary confounders, a significant inverse association was observed between intakes of total, soluble and insoluble dietary fiber and CVD risk, in the highest compared to the lowest tertiles (HR = 0.39, 95% CI = 0.18–0.83, HR = 0.19, 95% CI = 0.09–0.41, and HR = 0.31, 95% CI = 0.14–0.69, respectively). Inverse relations were observed between risk of CVD and dietary fiber from legumes, fruits and vegetables; however, dietary fiber intake from grain and nut sources was not related to risk of CVD. Conclusion: Our findings confirmed that higher intakes of dietary fiber from different sources is associated with CVD events and modify its major risk-related factors