Tabriz University of Medical Sciences Journal of Cardiovascular and Thoracic Research 2008-5117 18 3 2026 09 28 Dietary Antioxidant Index (DAI) and Its Association with Ischemic Heart Disease: Evidence from a Case-Control Study 219 226 10.34172/jcvtr.33530 EN Saba Moradi https://orcid.org/0009-0003-0409-3769 Raha Manouchehrian Elham Elhami Leila Dehghanian Yeganeh Shekari Atefeh Tahavorgar Ali Moradi Mohammadtaghi Ghorbani Hesari Faezeh Tejareh Maryam Gholamalizadeh Sara Khoshdooz Marjan Ajami https://orcid.org/0000-0002-6820-550X Saeid Doaei https://orcid.org/0009-0008-7193-5117 Journal Article 10.34172/jcvtr.33530 2025 03 13 2026 07 02 Introduction: Ischemic heart disease (IHD) is a chronic condition associated with various cardiovascular complications. Oxidative stress was reported to play a prominent role in the development of IHD. The Dietary Antioxidant Index (DAI) measures dietary antioxidant capacity, yet its association with IHD odds remains unclear. This study aimed to investigate the link between IHD odds and DAI in Iranian adults. Methods: This case-control study included 443 cases with stable IHD and 443 controls without IHD. Dietary intake was assessed using a validated semi-quantitative food frequency questionnaire (FFQ) and Nutritionist IV software was applied to assess the intake of different types of dietary antioxidants. DAI was then calculated using Wright’s method. The multivariable logistic regression was used for statistical analysis and the adjustment of the confounders. Results: Patients with IHD had lower intakes of several micronutrients, including potassium, sodium, selenium, vitamin A, vitamin E, vitamin C, vitamin K, vitamin B12, lycopene, and choline. The cases had significantly lower total DAI scores compared to the controls. A significant inverse association was observed between IHD and total DAI score (OR=0.948, 95%CI: 0.912-0.985, P=0.006) and vitamin C (OR=0.803, 95%CI: 0.672-0.959, P=0.016). These associations remained significant after adjustment for energy, age, gender, marital status, job, physical activity, BMI, smoking, and alcohol consumption. Conclusion: Our findings suggest a significant inverse relationship between IHD and dietary antioxidant index may be associated with lower odds of IHD. Dietary antioxidant assessment may be beneficial as part of lifestyle counseling in high-odds patients.