Effects of bread fortification with pomegranate peel powder on inflammation biomarkers, oxidative stress, and mood status in patients with type 2 diabetes: A randomized placebo-controlled trial

Background : To assess the effects of bread fortified with pomegranate peel powder (PPP) on inflammation, oxidative stress, and mood indices in patients with type 2 diabetes mellitus (T2DM). Methods : In total, 90 T2DM patients were randomized to receive either bread fortified with 3.5% pomegranate peel powder (PPP) (n=45) or PPP-free bread for 12 weeks. Dietary intake throughout the trial was assessed via food records. Laboratory parameters, including total antioxidant capacity (TAC), malondialdehyde (MDA), high-sensitivity C-reactive protein (hs-CRP), and psychological disorders, including depression, anxiety, and stress, were assessed at the beginning and end of the study. Results: 77 diabetic patients completed the trial (PPP group = 39 and control group = 38). Based on the compliance assessment, adherence to the interventions was high in the trial. We detected significant reductions in hs-CRP levels (intervention group: change = -0.56 ± 1.29, P=0.01; control group: change = -0.81± 1.16, p<0.001) and depression scores (intervention group: change= -1.33 ± 3.66, P=0.04; control group): -1.44 ± 2.83, p=0.01). There was no significant difference between the groups. After adjusting for confounding factors, the significant effect within the group disappeared. Other variables, including MDA, TAC, anxiety, and stress, did not significantly change in the PPP-fortified bread group. Conclusion : While intake of PPP-fortified bread for 12 weeks did not significantly affect oxidative stress, hs-CRP, or mental health in T2DM patients, some positive outcomes related to inflammatory and mood states should be explored. Trial registration Iranian Registry of Clinical Trials : The trial was registered in the Iranian Registry of Clinical Trials (available at www.irct.ir, with ID: IRCT20191209045672N1) on 21/09/2020.