Background: Food security is defined as access, for all people at all times, to enough food for an active and healthy life. Food security includes: 1) the ready availability of nutritionally-adequate and safe food, and 2) an assured ability to acquire acceptable foods in socially acceptable ways. The increase in childhood as well as adulthood obesity and food insecurity has caused many recent investigations on obesity, food insecurity and some associated factors. However, there appears to be a lack of published information regarding some factors affecting obesity and food insecurity. This study aimed to determine the prevalence obesity and food insecurity and some associated factors among Yazd province primary school students in Iran.

Methods: Using two-stage cluster sampling, a total of 3245 students (1587 boys and 1658 girls), aged 9-11 years, were randomly selected from primary school pupils in Yazd, Iran. From these, 187 students having BMIs ≥95^th percentile, as defined by Hosseini et al. (1999), were identified as obese and 187 pupils of the same age and gender having BMIs between the 15^th and 85^th percentiles were selected as controls. Data were collected using 24-hour food-recall and USDA food insecurity questionnaires.

Results: We found that the prevalence of obesity among students aged 9-11 years was 13.3%, and the prevalence of food insecurity was 30.5%. Daily energy intakes, compared to those recommended by the RDA, carbohydrate intake and energy percentages from proteins and carbohydrates were higher in obese children, and all macronutrient intakes per kilogram of body weight were significantly higher. An association between obesity and food insecurity was observed with adjusted fat intake.

Conclusion: In conclusion, the prevalence of obesity and food insecurity is high among Yazd primary school students, and high-level intakes of energy, protein, carbohydrate are associated with obesity. Furthermore, variation in the rate of fat intake is a relative factor for food insecurity.