Efficacy of Curcumin on Inflammatory Biomarkers in Type 2 Diabetes: A Meta-Analysis of Clinical Trials and Animal Studies Systematic Review & Meta-Analysis (PRISMA 2020) Field: Botany & Complementary Medicine
DOI:
https://doi.org/10.65405/9wp1fk50Keywords:
Curcumin; Type 2 Diabetes Mellitus; TNF-α; IL-6; CRP; NF-κB; Meta-Analysis; Systematic Review; Inflammation; Complementary Medicine; PRISMA 2020Abstract
Background: Type 2 diabetes mellitus (T2DM) is among the most prevalent metabolic disorders worldwide, with the International Diabetes Federation estimating a global burden exceeding 537 million adults and projections pointing toward 783 million by 2045. Central to its pathogenesis is a state of chronic, low-grade inflammation driven by dysregulated cytokine release, persistent NF-κB activation, and adipokine imbalance. Curcumin, the principal polyphenolic constituent of Curcuma longa L. (Zingiberaceae), has attracted sustained scientific interest for its multi-target anti-inflammatory properties. Yet despite a growing body of trial-level evidence, no prior meta-analysis has concurrently integrated human randomized controlled trials (RCTs) and controlled animal experiments within a unified analytical framework.
Objectives: To evaluate the pooled efficacy of curcumin supplementation on the three principal inflammatory biomarkers of T2DM—tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and C-reactive protein (CRP)—across human and animal studies, and to identify the formulation, dosage, and duration parameters most predictive of therapeutic response.
Methods: A comprehensive literature search was conducted in PubMed/MEDLINE, Scopus, Web of Science, Cochrane CENTRAL, Embase, and Google Scholar. Study selection and data extraction adhered to PRISMA 2020 guidelines, with risk of bias assessed using Cochrane RoB 2.0 for RCTs and the SYRCLE tool for animal studies. Pooled effect sizes were expressed as weighted mean differences (WMD) or standardized mean differences (SMD) with 95% confidence intervals under a DerSimonian–Laird random-effects model.
Results: Twenty-eight studies met the eligibility criteria—18 RCTs collectively enrolling 1,382 T2DM patients and 10 controlled animal experiments. Curcumin supplementation produced statistically significant reductions in CRP (SMD = −0.59, 95% CI: −1.11 to −0.07, p = 0.03), TNF-α (WMD = −1.84 pg/mL, 95% CI: −2.91 to −0.77, p = 0.001), and IL-6 (WMD = −1.29 pg/mL, 95% CI: −2.16 to −0.42, p = 0.004). Substantial heterogeneity was observed across all biomarkers (I² = 58–71%), with formulation type emerging as the dominant moderator.
Conclusion: Curcumin exerts a consistent, mechanistically coherent anti-inflammatory effect in T2DM across both human and animal evidence. Enhanced-bioavailability formulations confer the largest benefits. These findings support curcumin's potential role as an adjunct anti-inflammatory strategy in T2DM management, pending confirmation by larger, standardized clinical trials.
Downloads
References
Adibian, M., Hodaei, H., Nikpayam, O., Sohrab, G., Hekmatdoost, A., & Hedayati, M. (2019). The effects of curcumin supplementation on high-sensitivity C-reactive protein, serum adiponectin, and lipid profile in patients with type 2 diabetes: A randomized, double-blind, placebo-controlled trial. Phytotherapy Research, 33(5), 1374–1383. https://doi.org/10.1002/ptr.6328
Alrashdi, B., Askar, H., Germoush, M., Fouda, M., Abdel-Farid, I., Massoud, D., Alzwain, S., Gadelmawla, M. H. A., & Ashry, M. (2024). Evaluation of the anti-diabetic and anti-inflammatory potentials of curcumin nanoparticle in diabetic rat induced by streptozotocin. Open Veterinary Journal, 14(12), 3375–3387. https://doi.org/10.5455/OVJ.2024.v14.i12.22
Alsulaim, A. K., Almutaz, T. H., Albati, A. A., & Rahmani, A. H. (2023). Therapeutic potential of curcumin, a bioactive compound of turmeric, in prevention of streptozotocin-induced diabetes through the modulation of oxidative stress and inflammation. Molecules, 29(1), 128. https://doi.org/10.3390/molecules29010128
ALTamimi, J. Z., AlFaris, N. A., Al-Farga, A. M., Alshammari, G. M., BinMowyna, M. N., & Yahya, M. A. (2021). Curcumin reverses diabetic nephropathy in streptozotocin-induced diabetes in rats by inhibition of PKCβ/p66Shc axis and activation of FOXO-3a. The Journal of Nutritional Biochemistry, 87, 108515. https://doi.org/10.1016/j.jnutbio.2020.108515
Altobelli, E., Angeletti, P. M., Marziliano, C., Mastrodomenico, M., Giuliani, A. R., & Petrocelli, R. (2021). Potential therapeutic effects of curcumin on glycemic and lipid profile in uncomplicated type 2 diabetes: A meta-analysis of randomized controlled trial. Nutrients, 13(2), 404. https://doi.org/10.3390/nu13020404
Asadi, S., Gholami, M. S., Siassi, F., Qorbani, M., Khamoshian, K., & Sotoudeh, G. (2019). Nano curcumin supplementation reduced the severity of diabetic sensorimotor polyneuropathy in patients with type 2 diabetes mellitus: A randomized double-blind placebo-controlled clinical trial. Complementary Therapies in Medicine, 43, 253–260. https://doi.org/10.1016/j.ctim.2019.02.014
Badr, A. M., Sharkawy, H., Farid, A. A., et al. (2020). Curcumin induces regeneration of β cells and suppression of phosphorylated-NF-κB in streptozotocin-induced diabetic mice. Journal of Basic and Applied Zoology, 81, 22. https://doi.org/10.1186/s41936-020-00156-0
Camilotti, B., Chagas, A., Valadares, L., Damião, S., Macedo, L., Assis, F., & Silva, M. (2024). A systematic review and meta-analysis of the anti-inflammatory benefits of curcumin supplementation in individuals with metabolic syndrome and related diseases. Revista DELOS, 17, e2159. https://doi.org/10.55905/rdelosv17.n60-048
Chuengsamarn, S., Rattanamongkolgul, S., Luechapudiporn, R., Phisalaphong, C., & Jirawatnotai, S. (2012). Curcumin extract for prevention of type 2 diabetes. Diabetes Care, 35(11), 2121–2127. https://doi.org/10.2337/dc12-0116
Ebrahimzadeh, A., Abbasi, F., Ebrahimzadeh, A., Jibril, A. T., & Milajerdi, A. (2021). Effects of curcumin supplementation on inflammatory biomarkers in patients with rheumatoid arthritis and ulcerative colitis: A systematic review and meta-analysis. Complementary Therapies in Medicine, 61, 102773. https://doi.org/10.1016/j.ctim.2021.102773
El-Rakabawy, O. M., Elkholy, A. A., Mahfouz, A. A., Abdelsalam, M. M., & El Wakeel, L. M. (2025). Curcumin supplementation improves the clinical outcomes of patients with diabetes and atherosclerotic cardiovascular risk. Scientific Reports, 15, 28358. https://doi.org/10.1038/s41598-025-09783-5
Febriza, A., Zahrah, A. A., Andini, N. S., Usman, F., & Idrus, H. H. (2024). Potential effect of curcumin in lowering blood glucose level in streptozotocin-induced diabetic rats. Diabetes, Metabolic Syndrome and Obesity, 17, 3305–3313. https://doi.org/10.2147/DMSO.S468059
Ganugula, R., Arora, M., Jaisamut, P., Wiwattanapatapee, R., Jørgensen, H. G., Venkatpurwar, V. P., Zhou, B., Rodrigues Hoffmann, A., Basu, R., Guo, S., & Majeti, N. V. R. K. (2017). Nano-curcumin safely prevents streptozotocin-induced inflammation and apoptosis in pancreatic beta cells for effective management of Type 1 diabetes mellitus. British Journal of Pharmacology, 174(13), 2074–2084. https://doi.org/10.1111/bph.13816
Hewlings, S. J., & Kalman, D. S. (2017). Curcumin: A review of its effects on human health. Foods, 6(10), 92. https://doi.org/10.3390/foods6100092
Hsueh, H. C., Ho, G. R., Tzeng, S. I., Liang, K. H., & Horng, Y. S. (2025). Effects of curcumin on serum inflammatory biomarkers in patients with knee osteoarthritis: A systematic review and meta-analysis of randomized controlled trials. BMC Complementary Medicine and Therapies, 25(1), 237. https://doi.org/10.1186/s12906-025-04951-6
Hussain, Y., Khan, H., Alotaibi, G., Khan, F., Alam, W., Aschner, M., Jeandet, P., & Saso, L. (2022). How curcumin targets inflammatory mediators in diabetes: Therapeutic insights and possible solutions. Molecules, 27(13), 4058. https://doi.org/10.3390/molecules27134058
Jabczyk, M., Nowak, J., Hudzik, B., & Zubelewicz-Szkodzińska, B. (2021). Curcumin in metabolic health and disease. Nutrients, 13(12), 4440. https://doi.org/10.3390/nu13124440
Kavyani, Z., Najafi, K., Naghsh, N., Karvane, H. B., & Musazadeh, V. (2024). The effects of curcumin supplementation on biomarkers of inflammation, oxidative stress, and endothelial function: A meta-analysis of meta-analyses. Prostaglandins & Other Lipid Mediators, 174, 106867. https://doi.org/10.1016/j.prostaglandins.2024.106867
Lee, Y. M., & Kim, Y. (2024). Is curcumin intake really effective for chronic inflammatory metabolic disease? A review of meta-analyses of randomized controlled trials. Nutrients, 16(11), 1728. https://doi.org/10.3390/nu16111728
Marton, L. T., Pescinini-E-Salzedas, L. M., Camargo, M. E. C., Barbalho, S. M., Haber, J. F. D. S., Sinatora, R. V., Detregiachi, C. R. P., Girio, R. J. S., Buchaim, D. V., & Cincotto Dos Santos Bueno, P. (2021). The effects of curcumin on diabetes mellitus: A systematic review. Frontiers in Endocrinology, 12, 669448. https://doi.org/10.3389/fendo.2021.669448
Mokgalaboni, K., Mashaba, R. G., Phoswa, W. N., & Lebelo, S. L. (2024). Curcumin attenuates hyperglycemia and inflammation in type 2 diabetes mellitus: Quantitative analysis of randomized controlled trial. Nutrients, 16(23), 4177. https://doi.org/10.3390/nu16234177
Nurcahyanti, A. D. R., Cokro, F., Wulanjati, M. P., Mahmoud, M. F., Wink, M., & Sobeh, M. (2022). Curcuminoids for metabolic syndrome: Meta-analysis evidences toward personalized prevention and treatment management. Frontiers in Nutrition, 9, 891339. https://doi.org/10.3389/fnut.2022.891339
Panahi, Y., Khalili, N., Sahebi, E., Namazi, S., Simental-Mendía, L. E., Majeed, M., & Sahebkar, A. (2018). Effects of curcuminoids plus piperine on glycemic, hepatic and inflammatory biomarkers in patients with type 2 diabetes mellitus: A randomized double-blind placebo-controlled trial. Drug Research, 68(7), 403–409. https://doi.org/10.1055/s-0044-101752
Peng, Y., Ao, M., Dong, B., Jiang, Y., Yu, L., Chen, Z., Hu, C., & Xu, R. (2021). Anti-inflammatory effects of curcumin in the inflammatory diseases: Status, limitations and countermeasures. Drug Design, Development and Therapy, 15, 4503–4525. https://doi.org/10.2147/DDDT.S327378
Ramos-Martínez, E., Falfán-Valencia, R., Pérez-Rubio, G., García-Vázquez, F. J., Rojas-Serrano, J., Heredia-Antúnez, A. P., Aristi-Urista, G., & Chavarria-Krauser, A. (2026). Treatment with curcumin delays the development of type 1 diabetes mellitus by decreasing proinflammatory cytokines in non-obese diabetic mice. Diabetology, 7(2), 31. https://doi.org/10.3390/diabetology7020031
Rivera-Mancía, S., Trujillo, J., & Pedraza Chaverri, J. (2018). Utility of curcumin for the treatment of diabetes mellitus: Evidence from preclinical and clinical studies. Journal of Nutrition & Intermediary Metabolism, 14, 29–41. https://doi.org/10.1016/j.jnim.2018.05.001
Sciberras, J. N., Galloway, S. D., Fenech, A., Grech, G., Farrugia, C., Duca, D., & Mifsud, J. (2015). The effect of turmeric (curcumin) supplementation on cytokine and inflammatory marker responses following 2 hours of endurance cycling. Journal of the International Society of Sports Nutrition, 12(1). https://doi.org/10.1186/s12970-014-0066-3
Tian, J., Feng, B., & Tian, Z. (2022). The effect of curcumin on lipid profile and glycemic status of patients with type 2 diabetes mellitus: A systematic review and meta-analysis. Evidence-Based Complementary and Alternative Medicine, 2022, 8278744. https://doi.org/10.1155/2022/8278744
Uchio, R., Okuda-Hanafusa, C., Sakaguchi, H., Saji, R., Muroyama, K., Murosaki, S., Yamamoto, Y., & Hirose, Y. (2024). Curcuma longa extract reduces serum inflammatory markers and postprandial hyperglycemia in healthy but borderline participants: A randomized, double-blind, and placebo-controlled trial. Frontiers in Nutrition, 11, 1324196. https://doi.org/10.3389/fnut.2024.1324196
Yaikwawong, M., Jansarikit, L., Jirawatnotai, S., & Chuengsamarn, S. (2024). The effect of curcumin on reducing atherogenic risks in obese patients with type 2 diabetes: A randomized controlled trial. Nutrients, 16(15), 2441. https://doi.org/10.3390/nu16152441
Yaikwawong, M., Jansarikit, L., Jirawatnotai, S., & Chuengsamarn, S. (2025). Curcumin for inflammation control in individuals with type 2 diabetes mellitus and metabolic dysfunction-associated steatotic liver disease: A randomized controlled trial. Nutrients, 17(12), 1972. https://doi.org/10.3390/nu17121972
Zakerkish, M., Hemmati, A., Jalili Sebardan, F., & Shakiba Maram, N. (2023). Effect of Curcumex on serum lipid profile and fasting blood glucose, HbA1c, and insulin resistance levels in type 2 diabetic patients: A randomized, double-blind clinical trial. Jundishapur Journal of Natural Pharmaceutical Products, 18(3), e136383. https://doi.org/10.5812/jjnpp-136383
Zhang, F., & Niu, B. (2025). Effect of curcumin on inflammatory markers and disease activity in patients with rheumatoid arthritis: A meta-analysis. Medicine, 104(48), e46177. https://doi.org/10.1097/MD.0000000000046177
