Background & objectives: Nitrate is one of the major contaminants in food and water. Excess intake of this substance can increase the risk of stomach cancer and also cause other health problems. The objectives of this study were estimation of dietary nitrate consumption in the Varzaghan with high and Parsabad with low stomach cancer incidence in country, and also the comparison dietary nitrate consumption with World Health Organization standards.

  Methods: In this comparative study performed during autumn and spring of 2011 about 216 food samples (including all food groups) and drinking water collected and their nitrate concentration was determined by colorimetric method. Then daily dietary consumption of nitrate calculated based on daily diet of each person (according to national study on food consumption pattern in Iran) and nitrate concentration in each group of food and drinking water.

  Results: Daily consumption of nitrate in Varzaghan and Parsabad was 8.53 ± 0.35 and 8.17 ± 0.54 mg per kg of body weight (of adults), respectively, which is much greater than the amount recommended by FAO/WHO (0-3.7 mg per kg of body weight). Significant difference was not observed in the dietary consumption of nitrate in two cities at studied period (P> 0.05).

  Conclusion: Despite of no significant difference in dietary consumption of nitrate in two cities, the daily consumption of nitrate in both of studied cities was significantly greater than the recommended level. Therefore monitoring sources of contamination and reduction of environmental pollution for decreasing food nitrate concentration are recommended.