Effect ofNigella sativasupplementation over a one-year period on lipid levels, blood pressure and heart rate in type-2 diabetic patients receiving oral hypoglycemic agents: nonrandomized clinical trial

Abstract

BACKGROUNDDiabetic patients with hypertension and dyslipidemia are at a high risk of cardiovascular complications.OBJECTIVESTo determine the effect of Nigella sativa supplementation on the lipid profile, mean arterial pressure, and heart rate in persons with type 2 diabetes on oral hypoglycemic agents (OHA).DESIGNSingle-blind, nonrandomized.SETTINGDiabetes clinic of a university hospital in Saudi Arabia.PATIENTS AND METHODSType-2 diabetic patients were recruited by purposive sampling and assigned to treatment or control at the discretion of the investigator with the patient blinded to treatment. Before the intervention and every 3 months thereafter until the end of the treatment period, the following parameters were measured: triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), and body mass index (BMI). Results at the baseline and each subsequent visit were compared between the two groups.MAIN OUTCOME MEASURE(S)Lipid and cardiovascular parameters, and BMI.RESULTSFifty-seven patients were assigned to receive N sativa 2 g daily for one year and 57 were assigned to receive an identical regimen of placebo, along with OHA. A significant decrease in HDL-C and increase in the TC/HDL-C and LDL-C/HDL-C ratios were seen in the control group. The N sativa group had a significant decline in TC, LDL-C, TC/HDL-C and LDL-C/HDL-C ratios, compared with the respective baseline data and the control group. HDL-C was significantly elevated in the N sativa group. The control group showed a significant elevation in MAP. The N sativa group had a significant reduction in SBP, DBP, MAP and HR and a significant decrease in DBP, MAP and HR as compared with the control group.CONCLUSIONN sativa supplementation improves total cholesterol, mean arterial pressure and heart rate in type 2 diabetes patients on oral hypoglycemic agents.LIMITATIONSThere were 9 subjects in each group lost to follow up; thus the sample size could not be maintained as per the sample size calculation. The study was nonrandomized and thus there was a possibility of allocation bias. (Clinical trial registration number: CTRI/2013/06/003781, Clinical Trial Registry of India).

The effects of black seed supplementation on cardiovascular risk factors in patients with nonalcoholic fatty liver disease: A randomized, double‐blind, placebo‐controlled clinical trial

“…It seems that the normal lipid profile of both groups at the beginning of the study is responsible for these results. Previous studies in patients with hyperlipidemia have shown that 2 g/day N. sativa supplementation reduces blood lipids significantly (Badar et al, ; Farzaneh et al, ; Sabzghabaee et al, ). The effects of black seed on the lipid profile are due to presence of antioxidants such as thymoquinone, tocopherol, and phytosterol, which can prevent LDL‐C oxidation, inhibit intestinal absorption of cholesterol, reduce the production of hydroxyl–methyl–glutaryl coenzyme A reductase (HMGCR), and improve the expression of LDL receptor genes by reducing intracellular cholesterol (Al‐Naqeeb & Ismail, ; Brufau, Canela, & Rafecas, ; Mariod, Ibrahim, Ismail, & Ismail, ).…”

“…They were milled every 4 weeks, placed in the capsules, and delivered to the participants. We chose 2 g/day because previous studies have reported the beneficial effects of this dosage on other health-related outcomes (Badar et al, 2017;Farzaneh, Nia, Mehrtash, Mirmoeini, & Jalilvand, 2014;Hussain, Tunio, Arain, & Shaikh, 2017;Sabzghabaee, Dianatkhah, Sarrafzadegan, Asgary, & Ghannadi, 2012). N. sativa seeds contain protein (26.7%), fat (28.5%), carbohydrates (24.9%), crude fiber (8.4%), and total ash (4.8%).…”

“…It has been shown that thymoquinone alleviates NAFLD through reduction of oxidative stress, inflammation, and apoptosis in experimental model of disease (Awad, Al Haleem, El-Bakly, & Sherief, 2016). Moreover, it has been shown that N. sativa can reduce serum triglycerides (TGs) and low-density lipoprotein cholesterol (LDL-C) level, whereas improve glycemic indices in diabetic patients (Badar et al, 2017;Ibrahim et al, 2014;Kaatabi et al, 2015).…”

Antihypertensive Effects of Nigella Sativa: Weighing the Evidence

“…Following the literature search, four articles were found to be eligible for this evidence-based case report [13][14][15][16] the design and summary of the articles can be found in table 2.…”

“…These two articles are prospective cohort studies with a level of evidence of 2b. The study by Badar A, et al [13] has a larger sample size and longer duration compared with the study by Rizka A, et al [14]. The former is a single-blind non-randomized clinical trial, whereas the latter is a double-blind randomized controlled trial.…”