Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 48 1 2019 01 16 162 170 Zahra BAHADORAN Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran Asghar GHASEMI Endocrine Physiology Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran Parvin MIRMIRAN Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran Yadollah MEHRABI Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Fereidoun AZIZI Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran Farzad HADAEGH Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2019 01 16 Background: The aim of this study was calibration of a nitrate (NO3)/nitrite (NO2) database for estimated its dietary intakes. Methods: Overall, 250 healthy Tehranian adults were assessed in 2015 for dietary intakes of NO3 and NO2 and its serum and urine concentration. Food composition values for NO3 and NO2 were derived from a recent survey conducted on frequently consumed food items among Iranians. The correlation of dietary intakes of NO3/NO2 and its urinary and serum values was evaluated. Results: Mean (±SD) intakes of dietary NO3 and NO2 were 505±160 and 7.7±2.2 mg/d, respectively. The correlation coefficient of intake and urinary NO3 was 0.83 (95% CI=0.56-0.91) and 0.57 (95% CI=0.49-0.67) in men and women, respectively. A moderate agreement was also observed between NO2 intake and its urinary levels (r=0.27, 95% CI=0.13-0.37, and 0.29, 95% CI=0.17-0.41, in men and women, respectively). Conclusion: Using a national database of NO3 and NO2 content of food items along with a valid food frequency questionnaire could provide a valid estimation of dietary intakes of NO3 in the target population.   https://ijph.tums.ac.ir/index.php/ijph/article/view/15952 https://ijph.tums.ac.ir/index.php/ijph/article/download/15952/6267