Effect of date seed (Phoenix dactylifera) supplementation as functional food on cardiometabolic risk factors, metabolic endotoxaemia and mental health in patients with type 2 diabetes mellitus: a blinded randomised controlled trial protocol

INTRODUCTION: Recently, the improvement of chronic hyperglycaemia-related damage of type 2 diabetes mellitus (T2DM) through functional food consumption has attracted the attention of many clinicians. This study aims to determine the effectiveness of date seed powder (DSP) as a functional food (prebiotic) on the cardiometabolic risk factors, oxidative stress, anti-/inflammatory biomarkers, metabolic endotoxaemia (gut microbiota), adipokines, hypothalamic–pituitary–adrenal axis biomarkers, immune system, anthropometric indices and mental health in patients with T2DM. METHODS: This study protocol will be conducted as randomised, triple-blind, placebo-controlled trial with the inclusion of 48 patients with T2DM. The participants will be randomly assigned into two equal groups of intervention (n=24) and placebo (n=24) and receive 5 g/day of DSP or placebo for 8 weeks, respectively. At baseline and post-intervention, fasting blood samples will be collected to assess the serum levels of lipid profile, glycaemic indices, antioxidant and oxidative stress, anti-/inflammatory biomarkers, lipopolysaccharide, 8-hydroxy-guanine, adipokines, hypothalamic–pituitary–adrenal axis biomarkers, immune system and mental health. Data will be analysed using the SPSS software (V.16.0). To compare the quantitative variables, paired and unpaired Student’s t-tests and covariance analyses will be used. DISCUSSION: In this study, the potential effects of DSP on patients with T2DM will be evaluated for the first time. It is hoped that the results would increase the body of scientific knowledge about DSP supplementation on the cardiometabolic risk factors, oxidative stress, anti-/inflammatory biomarkers, metabolic endotoxaemia, adipokines, hypothalamic–pituitary–adrenal axis biomarkers, immune system, anthropometric indices and mental health in patients with T2DM. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethical Committee of the Tabriz University of Medical Sciences, Tabriz, Iran (code: IR.TBZMED.REC.1400.752). TRIAL REGISTRATION NUMBER: Iranian Registry of Clinical Trials (www.irct.ir/IRCT20150205020965N10).