The Comprehensive Systematic Review of Association of Vit D Deficiency to The Prevalence of Insulin Resistance
Keywords:
Vitamin D deficiency, Insulin resistance, Type 2 diabetes, HOMA-IR, Metabolic syndromeAbstract
Introduction: Vitamin D deficiency has emerged as a global health concern with potential implications for metabolic health, particularly insulin resistance—a key precursor to type 2 diabetes and metabolic syndrome. Despite extensive research, the nature, strength, and causality of this association remain debated due to heterogeneous methodologies and conflicting intervention outcomes.
Methods: This comprehensive systematic review synthesized evidence from 80 studies following rigorous screening and data extraction protocols. Studies were included if they examined the association between vitamin D deficiency (defined by serum 25(OH)D levels) and insulin resistance (assessed via validated methods like HOMA-IR) in adults, excluding those focused solely on supplementation, type 1 diabetes, or pregnancy.
Results: The evidence consistently demonstrates a significant inverse association between vitamin D status and insulin resistance across diverse populations. Observational studies showed weak to moderate inverse correlations (r ranging from -0.134 to -0.631), with stronger associations in diabetic (pooled r ≈ -0.255) versus non-diabetic populations (pooled r ≈ -0.073) (Rafiq & Jeppesen, 2021; Alshahrani et al., 2025). Meta-analyses confirmed that higher vitamin D levels are associated with a reduced risk of type 2 diabetes (RR = 0.65) and prediabetes (RR = 0.49) (Mohammadi et al., 2021). The association was notably amplified by obesity, with correlations strengthening from r = -0.150 in normal-weight individuals to r = -0.257 in obese individuals (Rafiq & Jeppesen, 2021). However, RCTs on vitamin D supplementation yielded mixed results; while some showed improvement in insulin resistance, particularly in those with baseline glucose intolerance, others reported no significant effect in healthy or normoglycemic individuals (Mitri et al., 2011; von Hurst et al., 2009; Grimnes et al., 2011).
Discussion: The relationship between vitamin D deficiency and insulin resistance is complex and modified by factors such as baseline metabolic status, BMI, and ethnicity. The discordance between strong observational associations and inconsistent interventional findings suggests that vitamin D status may be a marker of overall metabolic health and adiposity rather than a directly modifiable causal factor in all populations. Mechanistic pathways—including effects on pancreatic β-cell function, insulin receptor expression, and systemic inflammation—provide biological plausibility but underscore the influence of confounding variables.
Conclusion: Vitamin D deficiency is consistently associated with a higher prevalence and severity of insulin resistance, particularly in individuals with obesity, prediabetes, or established type 2 diabetes. Maintaining adequate vitamin D status should be considered a component of metabolic health strategy. Supplementation may offer the greatest benefit for those with documented deficiency coupled with existing metabolic dysfunction, rather than as a universal preventive measure for insulin resistance.
References
A. Abukanna, Reem Falah A Alanazi, Fatimah Alruwaili, Asma Zaid M Alayyashi, and Farah Alanzi. “Vitamin D Deficiency as a Risk Factor for Diabetes and Poor Glycemic Control in Saudi Arabia: A Systematic Review.” Cureus, 2023.
A. Lizarraga, S. Lindenberg, G. Almind, and F. Lindenberg. “P–662 Study on D-Vitamin, AMH and Insulin Interrelation in Polycystic Ovary Syndrome (PCOS) Patients.” Human Reproduction, 2021.
A. Pittas, J. Lau, F. Hu, and B. Dawson-Hughes. “The Role of Vitamin D and Calcium in Type 2 Diabetes. A Systematic Review and Meta-Analysis.” Journal of Clinical Endocrinology and Metabolism, 2007.
A. Renzaho, J. Halliday, and C. Nowson. “Vitamin D, Obesity, and Obesity-Related Chronic Disease Among Ethnic Minorities: A Systematic Review.” Nutrition (Burbank, Los Angeles County, Calif.), 2011.
A. Tremblay, and Jo-Anne Gilbert. “Milk Products, Insulin Resistance Syndrome and Type 2 Diabetes.” Journal of the American College of Nutrition, 2009.
Aboud Al Hayani, and Ahlam Nasir. “Effect of Vitamin D Supplementation on Ovulation Among Women with PCO.” The Medical Journal of Cairo University, 2020.
Ahmed Altayeb Abbas Fadlallah, Miska Haroun Mohamed Hassan, Salma Farah, Solar Eltayeb Mohamed Gaffar, Ashraf Hayder Mahgoub Ali, Hasna Salem Alzahrani, Amirah Hassan Alhadhrami, and Fahad Salem M Alqahtani. “Evaluating the Effect of Vitamin D Supplementation on Type 2 Diabetes Risk: A Systematic Review.” Cureus, 2024.
Anuj Maheshwari, Ajoy Tewari, and V. Chavda. “635-P: Impact of Vitamin D Supplementation on Insulin Resistance Amongst People with Type 2 Diabetes in India.” Diabetes, 2024.
B. Núñez-García, J. Maldonado-Hernández, N. Álvarez-Licona, María Elizabeth Tejero-Barrera, M. Bernabe-García, Alva Belen Morales-Villar, Leticia Sebastián-Medina, M. Piña-Aguero, and J. M. Domínguez-Salgado. ““FokI Polymorphism of the Vitamin D Receptor Is Closely Related to a Reduced Insulin Sensitivity in Healthy Adults".” Clinical Nutrition Open Science, 2022.
B. Sowjanya. “Vitamin D Status, Insulin Resistance and Arterial Stiffness in Normal Healthy Subjects,” 2017.
Cem Ozcan, D. Çorapçıoğlu, and E. Cerit. “Relationship Between Vitamin D Levels and β Cell Function and Insulin Resistance.” Cureus, 2023.
Chunla He, Zhoumeng Lin, S. Robb, and A. Ezeamama. “Serum Vitamin D Levels and Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis.” Nutrients, 2015.
Dodi Novriadi, and Woris Christoper. “The Analysis Study of The Effect Vitamin D to Risk for Type 2 Diabetes Mellitus in People with Pre-Diabetes : A Comprehensive Systematic Review.” International Journal of Medical Science and Health Research, 2024.
Durgarao Y, P. Manjrekar, P. Adhikari, Chakrapani M, and Rukmini Ms. “Comprehensive Review on Diabetes Associated Cardiovascular Complications - The Vitamin D Perspective.” Cardiovascular & Haematological Disorders - Drug Targets, 2019.
E. Banitalebi, A. Hoseinzadeh, Zahra Mardanpour-Shahrekordi, and S. Amani-shalamzari. “Effect of Three Methods of Combined Training (Strength and Endurance) on Serum Adiponectin Levels and Insulin Resistance in Overweight Elderly Women,” 2015.
E. Jiffri. “Relationship Between Serum Vitamin D, Adipokines and Dyslipidemia in Type 2 Diabetes Mellitus,” 2018.
Elisa Cipponeri, M. G. Tarsitano, Elisabetta Falbo, and Caterina Conte. “Insulin Resistance in Type 1 Diabetes: Is There a Role for Vitamin D? A Systematic Review of the Evidence.” Discover Endocrinology and Metabolism, 2025.
Esra Tajik, and Fatemeh Amirasgari. “Effect of Vitamin D on Glucose Homeostasis and Insulin Sensitivity and Resistance in Type 2 Diabetes: A Systematic Review,” 2020.
F. Çağlar, N. Isıksacan, Nursel Kocamaz, and F. Akturk. “The Association Among Vitamin D, Insulin Resistance, and Obesity in Turkish Women,” 2017.
F. Qian, Yanjun Guo, Heike Gibson, Natalya Gomelskaya, Yanyan Liu, Olga V. Demler, N. Cook, et al. “Abstract 11848: Biomarkers of Glucose-Insulin Homeostasis, Randomized Treatment With Omega-3 and Vitamin D Supplementation, and Incident Type 2 Diabetes: Prospective Analysis From the Vitamin D and Omega-3 Trial (VITAL).” Circulation, 2021.
Fei‐fei Han, Yali Lv, Li-li Gong, He Liu, Zi-rui Wan, and Lihong Liu. “VDR Gene Variation and Insulin Resistance Related Diseases.” Lipids in Health and Disease, 2017.
G. Grimnes, Y. Figenschau, B. Almås, and R. Jorde. “Vitamin D, Insulin Secretion, Sensitivity, and Lipids.” Diabetes, 2011.
Gaurab Bhaduri, S. Samajdar, Subhro Chakraborty, Banshi Saboo, and Shashank R. Joshi. “Prevalence and Risk Factors of Hypovitaminosis D Among Patients with Diabetes Mellitus from India: A Systematic Review and Meta-Analysis.” Diabetes & Metabolic Syndrome, 2025.
Geórgia Rosa Reis de Alencar, Lailton da Silva Freire, B. M. C. Pereira, Verbena R. da Silva, Aline Cronemberger Holanda, R. C. D. Moura, J. S. Severo, et al. “Effects of Vitamin D Status on Inflammatory Markers in Obese Subjects: A Systematic Review,” 2020.
H. Ahmed, N. N. Hilal, and Mohamed Ghalib Zakari. “Evaluation of Vitamin D in Patients with Type 2 Diabetes Mellites.” South Asian Research Journal of Pharmaceutical Sciences, 2023.
H. Khan, S. Kunutsor, O. Franco, and Rajiv Chowdhury. “Vitamin D, Type 2 Diabetes and Other Metabolic Outcomes: A Systematic Review and Meta-Analysis of Prospective Studies.” Proceedings of the Nutrition Society, 2012.
Hamid Nasri, and M. Rafieian-kopaei. “Effect of Vitamin D on Insulin Resistance and Nephropathy in Type 2 Diabetes.” Journal of Research in Medical Sciences, 2014.
Humaira Kauser, Jaimee J Palakeel, Mazin Ali, Phani Chaduvula, Sanika Chhabra, Smriti Lamsal Lamichhane, Vaiishnavi Ramesh, et al. “Factors Showing the Growing Relation Between Vitamin D, Metabolic Syndrome, and Obesity in the Adult Population: A Systematic Review.” Cureus, 2022.
I. G. Zhoukovskaya, and I. R. Yakupova. “Effect of Vitamin D on Women’s Somatic and Reproductive Health.” Medical Council, 2020.
J. Daniel, Priscila Ribas de Farias Costa, Marcos Pereira, and A. M. Oliveira. “Vitamin D Deficiency and Cardiometabolic Risk Factors in Adolescents: Systematic Review and Meta-Analysis.” Reviews in Endocrine & Metabolic Disorders, 2022.
J. H. Mahmoud, and Iktifaa Abdul Hamid Muhammad. “Study of Concentrations of Some Vitamins in Women with Type 2 Diabetes and Insulin Resistance.” Journal Port Science Research, 2025.
J. Mitri, M. Muraru, and A. Pittas. “Vitamin D and Type 2 Diabetes: A Systematic Review.” European Journal of Clinical Nutrition, 2011.
Ji-Chang Zhou, Yu-mei Zhu, Zheng Chen, Jun-Luan Mo, Feng-Zhu Xie, Ying-Hong Wen, P. Guo, et al. “Oral Vitamin D Supplementation Has a Lower Bioavailability and Reduces Hypersecretion of Parathyroid Hormone and Insulin Resistance in Obese Chinese Males.” Public Health Nutrition, 2014.
Johanna Parker, Omar Hashmi, D. Dutton, A. Mavrodaris, S. Stranges, N. Kandala, A. Clarke, and O. Franco. “Levels of Vitamin D and Cardiometabolic Disorders: Systematic Review and Meta-Analysis.” Maturitas, 2010.
L. Gabel, Michael D. Brown, R. Ferrell, M. Korytkowski, J. Zmuda, S. D. McCole, and J. Hagberg. “VITAMIN D RECEPTOR GENOTYPE AND INSULIN SENSITIVITY IN POSTMENOPAUSAL WOMEN OF VARIOUS PHYSICAL ACTIVITY LEVELS,” 2002.
Li Li, and Xiao-hong Niu. “Correlation Study Between Vitamin D Level and Glucose Metabolism, Lipid Metabolism, Insulin Resistance, Early Secretory Function of Pancreatic Islets in Postmenopausal Women with Type 2 Diabetes,” 2016.
Ligia J. Dominguez, Nicola Veronese, Eliana Marrone, Carla Di Palermo, Candela Iommi, Rosaria Ruggirello, Carla Caffarelli, S. Gonnelli, and M. Barbagallo. “Vitamin D and Risk of Incident Type 2 Diabetes in Older Adults: An Updated Systematic Review and Meta-Analysis.” Nutrients, 2024.
Lijie Sun, Ji-Xuan Lu, Xinyou Li, Tian-Sheng Zheng, and Xiao-rong Zhan. “Effects of Vitamin D Supplementation on Glucose and Lipid Metabolism in Patients with Type 2 Diabetes Mellitus and Risk Factors for Insulin Resistance.” World Journal of Diabetes, 2023.
Lu Yu, Yu Zhai, and S. Shen. “Association Between Vitamin D and Prediabetes.” Medicine, 2020.
Lucian Batista de Oliveira, Mariana Andrade de Figueiredo Martins Siqueira, Rafael Buarque de Macedo Gadêlha, Jessica Garcia, and Francisco Bandeira. “Vitamin D Deficiency in Patients Hospitalized for Heart Failure Living in the Tropics.” International Journal of Heart Failure, 2024.
M. Hosseini, Mohammad Javad Bahoosh, G. Alishiri, N. Khalili, and Habib Yaribeygi. “The Effects of Plasma Levels of Vitamin D3 on Insulin Resistance and Biochemical Factors of Plasma in Patients with Type 2 Diabetes,” 2018.
M. S. Al-dahr. “Relation Between 25-Hydroxyvitamin D, Systemic Inflammation and Endothelial Function Biomarkers in Diabetic Nephropathy.” Gastroenterology: Medicine & Research, 2020.
Ming-Wei Lin, and Meng-Hsing Wu. “The Role of Vitamin D in Polycystic Ovary Syndrome.” The Indian Journal of Medical Research, 2015.
Mitku Mammo Taderegew, G. Woldeamanuel, Alemayehu Wondie, Atsede Getawey, Abera Nesiru Abegaz, and Fentahun Adane. “Vitamin D Deficiency and Its Associated Factors Among Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis.” BMJ Open, 2023.
Mohammad S. Alshahrani, Mohammed Ahmed Alqahtani, H. A. Alabdullah, Hamoud Meshal Alshammari, Reem Jaber Suhluli, Ahmed Ghali Aladhab, Jafar Radhi Albu Mijdad, et al. “The Association Between Vitamin D Deficiency and Insulin Resistance in Patients with Type 2 Diabetes: A Meta-Analysis.” Journal of Posthumanism, 2025.
Muntaha A. Arif, Manal K. Rasheed, and Ammar A. Ismaeel. “Study Some Biochemical Parameters in Patients with Coronary Artery Disease with and Without Type 2 Diabetes.” Journal of the Faculty of Medicine Baghdad, 2024.
N. Al-Daghri. “Vitamin D in Saudi Arabia: Prevalence,distribution and Disease Associations.” Journal of Steroid Biochemistry and Molecular Biology, 2018.
N. Chandrika, Usha Smr, and Victoria Kshetrimayum. “25-Hydroxycholecalciferol Levels and Its Equation with Lipid Parameters and Insulin Sensitivity in Obese and Non-Obese Young Adults: A Pilot Study.” Perspectives In Medical Research, 2022.
N. F. Maroufi, Pourya Pezeshgi, Zohreh Mortezania, Pirouz Pourmohammad, Reyhaneh Eftekhari, Mahmood Moradzadeh, Vahid Vahedian, and M. Nouri. “Association Between Vitamin D Deficiency and Prevalence of Metabolic Syndrome in Female Population: A Systematic Review.” Hormone Molecular Biology and Clinical Investigation, 2020.
N. Forouhi, J. Luan, A. Cooper, B. Boucher, and N. Wareham. “Baseline Serum 25-Hydroxy Vitamin D Is Predictive of Future Glycemic Status and Insulin Resistance.” Diabetes, 2008.
Nyein Wint Yee Theik, Oluwatimilehin E Raji, Priya Shenwai, Rutul Shah, Sahithi Reddy Kalluri, T. Bhutta, Hanan Hannoodee, Mahmoud Al Khalili, and Safeera Khan. “Relationship and Effects of Vitamin D on Metabolic Syndrome: A Systematic Review.” Cureus, 2021.
O. Tarçin, D. Yavuz, B. Ozben, A. Telli, A. V. Ogunc, Meral Yūksel, A. Toprak, et al. “Effect of Vitamin D Deficiency and Replacement on Endothelial Function in Asymptomatic Subjects.” Journal of Clinical Endocrinology and Metabolism, 2009.
P. Kishore, I. Choudhary, P. Satyanarayana, and U. Singh. “Association of Vitamin D with Insulin Resistance in Type 2 Diabetic Mellitus Patients,” 2017.
P. V. von Hurst, W. Stonehouse, and J. Coad. “Vitamin D Supplementation Reduces Insulin Resistance in South Asian Women Living in New Zealand Who Are Insulin Resistant and Vitamin D Deficient – a Randomised, Placebo-Controlled Trial.” British Journal of Nutrition, 2009.
Q. Qi, Yan Zheng, Tao Huang, J. Rood, G. Bray, F. Sacks, and L. Qi. “Vitamin D Metabolism-Related Genetic Variants, Dietary Protein Intake and Improvement of Insulin Resistance in a 2 Year Weight-Loss Trial: POUNDS Lost.” Diabetologia, 2015.
R. Sahebi, M. Rezayi, Maryam Emadzadeh, M. Salehi, Maryam Tayefi, S. Parizadeh, Negin Behboodi, et al. “The Effects of Vitamin D Supplementation on Indices of Glycemic Control in Iranian Diabetics: A Systematic Review and Meta-Analysis.” Complementary Therapies in Clinical Practice, 2019.
R. Sakthiswary, and A. Raymond. “The Clinical Significance of Vitamin D in Systemic Lupus Erythematosus: A Systematic Review.” PLoS ONE, 2013.
S. Kayaniyil, R. Retnakaran, S. Harris, R. Vieth, J. Knight, H. Gerstein, B. Perkins, B. Zinman, and A. Hanley. “Prospective Associations of Vitamin D With β-Cell Function and Glycemia.” Diabetes, 2011.
S. Mohammadi, Zahra Hajhashemy, and P. Saneei. “Serum Vitamin D Levels in Relation to Type-2 Diabetes and Prediabetes in Adults: A Systematic Review and Dose–Response Meta-Analysis of Epidemiologic Studies.” Critical Reviews in Food Science and Nutrition, 2021.
S. Parizadeh, M. Rezayi, Reza Jafarzadeh-Esfehani, A. Avan, H. Ghazizadeh, Maryam Emadzadeh, R. Sahebi, G. Ferns, and M. Ghayour-Mobarhan. “Association of Vitamin D Status With Liver and Kidney Disease: A Systematic Review of Clinical Trials, and Cross-Sectional and Cohort Studies.” International Journal for Vitamin and Nutrition Research. Internationale Zeitschrift Fur Vitamin- Und Ernahrungsforschung. Journal International de Vitaminologie Et de Nutrition, 2019.
S. Pattman. “Rising Serum 25-Hydroxy-Vitamin D Levels After Weight Loss in Obese Women Correlate with Improvement in Insulin Resistance,” 2011.
S. Savastano, C. Somma, and A. Colao. “Vitamin-D & Prediabetes: A Promising Ménage in the Indian Scenario.” The Indian Journal of Medical Research, 2013.
S. Wannamethee. “6. Vitamin D and Cardiovascular Disease and Heart Failure Prevention,” 2017.
Seth I. Sokol, Michael Grushko, V. Srinivas, and J. Crandall. “Relationship Between Vitamin D Deficiency, Post‐challenge Hyperglycemia, and Endothelial Function in Healthy Older Adults.” Journal of Diabetes, 2012.
Seyed-Amir Tabatabaeizadeh, and Niayesh Tafazoli. “The Role of Vitamin D in Prevention of Type 2 Diabetes. A Meta-Analysis.” Clinical Nutrition ESPEN, 2020.
Shamaila Rafiq, and P. Jeppesen. “Insulin Resistance Is Inversely Associated with the Status of Vitamin D in Both Diabetic and Non-Diabetic Populations.” Nutrients, 2021.
———. “Is Hypovitaminosis D Related to Incidence of Type 2 Diabetes and High Fasting Glucose Level in Healthy Subjects: A Systematic Review and Meta-Analysis of Observational Studies.” Nutrients, 2018.
———. “Vitamin D Deficiency Is Inversely Associated with Homeostatic Model Assessment of Insulin Resistance.” Nutrients, 2021.
Sowjanya Bachali, bullet K Dasu, bullet K Ramalingam, and B. N. Naidu. “Vitamin D Deficiency and Insulin Resistance in Normal and Type 2 Diabetes Subjects.” Indian Journal of Clinical Biochemistry, 2012.
T. D. S. Ferreira, Márcia Regina Simas Gonçalves Torres, D. Valença, M. D. Rodrigues, J. Neto, R. Marques, Jeanny dos Santos, N. F. Gomes, and A. F. Sanjuliani. “Abstract 526: Serum Levels of 25 Hidroxyvitamin D and Its Association With Body Fat, Metabolic Profile, Inflammatory Biomarkers, Blood Pressure and Endothelial Function,” 2013.
T. Tzotzas, F. Papadopoulou, K. Tziomalos, S. Karras, Kostantinos Gastaris, P. Perros, and G. Krassas. “Rising Serum 25-Hydroxy-Vitamin D Levels After Weight Loss in Obese Women Correlate with Improvement in Insulin Resistance.” Journal of Clinical Endocrinology and Metabolism, 2010.
Tracy S Moreira-Lucas, A. Duncan, R. Rabasa‐Lhoret, R. Vieth, A. Gibbs, A. Badawi, and T. Wolever. “Effect of Vitamin D Fortified Cheese on Oral Glucose Tolerance in Individuals Exhibiting Marginal Vitamin D Status and an Increased Risk for Developing Type 2 Diabetes: A Double‐Blind, Randomized Placebo‐Controlled Clinical Trial.” The FASEB Journal, 2016.
V. Pergialiotis, N. Karampetsou, P. Panagopoulos, E. Trakakis, and N. Papantoniou. “The Effect of Vitamin D Supplementation on Hormonal and Glycaemic Profile of Patients with PCOS: A Meta‐analysis of Randomised Trials.” International Journal of Clinical Practice, 2017.
W. Mohammedsaeed. “Exploring the Interplay Between DHCR7, Vitamin D Deficiency, and Type 2 Diabetes Mellitus (T2DM): A Systematic Review.” Molecular Biology Reports, 2024.
Xingxing Lei, Qian-yi Zhou, Yan-mei Wang, Shunlian Fu, Zinan Li, and Qiu Chen. “Serum and Supplemental Vitamin D Levels and Insulin Resistance in T2DM Populations: A Meta-Analysis and Systematic Review.” Scientific Reports, 2023.
Y. Krul-Poel, Chantal Snackey, Y. Louwers, Paul Lips, C. B. Lambalk, J. Laven, and Suat Simsek. “The Role of Vitamin D in Metabolic Disturbances in Polycystic Ovary Syndrome: A Systematic Review.” European Journal of Endocrinology, 2013.
Yun-Yi Gao, T. Zheng, X. Ran, Yan Ren, Tao Chen, L. Zhong, Donge Yan, Fangfang Yan, Qianlin Wu, and H. Tian. “Vitamin D and Incidence of Prediabetes or Type 2 Diabetes: A Four-Year Follow-Up Community-Based Study.” Disease Markers, 2018.
Z. Kamali, S. Ziaei, A. Kazemnejad, and Maryam Movahedinejad. “The Relationship Between Insulin Resistance and Micronutrient Intake in Polycystic Ovary Syndrome Subgroups.” Journal of Nutrition and Food Security, 2023.
Zainab Nur-Eldeen Aziz, Basil O. Saleh, and Ansam Zeki Thaker. “Free Testosterone, Dihydrotestosterone, and Adiponectin in the Evaluation of Vitamin D Supplementation for Polycystic Ovarian Syndrome: A Metformin Comparative Study.” AL-Kindy College Medical Journal, 2024.
Zhitong Li, Shiwei Liu, Xingyu Li, Jinchang Liu, Xin Li, Yuxiang Zhao, and Yongliang Feng. “The Association Between the Triglyceride-Glucose Index and Vitamin D Status: A Systematic Review and Meta-Analysis.” BMC Endocrine Disorders, 2024.
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