Curcumin Supplementation Reduces Inflammation, Neutrophil-to-Lymphocyte Ratio (NLR), and Antioxidant Status in Obese Patients with Type 2 Diabetes: a Randomized Controlled Trial

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by insulin resistance and impaired insulin secretion, and curcumin‐a polyphenolic compound derived from Curcuma longa‐has shown potential anti‐inflammatory and antioxidant effects. This randomized, double‐blind, placebo‐controlled trial evaluated the effects of 1500 mg/day curcumin supplementation for 12 months in 114 adults with T2DM, with assessments including fasting plasma glucose (FPG), glycated hemoglobin (HbA1c), insulin resistance (HOMA‐IR), inflammatory cytokines (IL‐6, IL‐1β, TNF‐α), high‐sensitivity C‐reactive protein (hs‐CRP), neutrophil‐to‐lymphocyte ratio (NLR), antioxidant markers (SOD, GPx, TAS), and malondialdehyde (MDA). Curcumin supplementation was associated with significant reductions in pro‐inflammatory cytokines (p < 0.001), hs‐CRP and NLR (p < 0.05), and with improved antioxidant status as shown by increased TAS, SOD, and GPx together with reduced MDA levels (p < 0.001). Additionally, improvements in metabolic parameters were observed, including lower FPG (112.0 mg/dL vs. 134.5 mg/dL; p < 0.001), HbA1c (6.10% vs. 6.40%; p < 0.05), and HOMA‐IR (4.88 vs. 6.71; p < 0.001). Overall, the findings suggest that long‐term curcumin supplementation may contribute to improved inflammatory, antioxidant, and glycemic profiles in obese individuals with T2DM; however, further multi‐center studies are needed to confirm these observations and clarify their clinical relevance.