Food security is considered a universal public health challenge, especially in children, because it affects their current physical, cognitive, and socio-emotional development and has long-term negative consequences (
1,
2). Household food insecurity is linked to manifestations of protein-energy malnutrition in children, including wasting, stunting, and underweight, particularly in developing countries (
1).
In the present study conducted in Ardabil province, a semi-developed province in north-west Iran, 61% of households experienced some degree of food insecurity. Various reports from different regions of Iran show differing rates of food insecurity based on the developmental conditions of the regions studied. For example, the prevalence of household food insecurity was 37.8% in Tehran (
25), the capital of Iran, in 2019, 33.4% in Esfahan (
26), a developed province in Iran, in 2017, and 32.9% in Yazd (
27), an industrial city in central Iran, in 2007. Studies conducted in less developed regions of Iran, including Zabol (
18) and Zahedan (
28,
29), reported higher prevalence rates of food insecurity (42% in Zabol in 2019, 58.8% in Zahedan in 2017, and 66% in Zahedan in 2022), which are comparable to or lower than the rate found in our study. The high food insecurity rate in our study population may be due to recent unprecedented inflation and a dramatic increase in the cost of food items in Iran. It should also be noted that in the studies cited above, food insecurity was not measured using the same module, and the sociodemographic characteristics (such as place of residence and parents’ education) of the studied households were not the same.
We found that in the subgroup of our study sample with the highest food insecurity score (quartile 4), family income was significantly lower compared to those with the lowest food insecurity score (quartile 1). The average family income in quartile 4 was remarkably lower than the current poverty threshold for a four-person family in Iran. Several studies in both developing and developed countries have indicated that economic poverty is closely related to elevated levels of food insecurity, and the incidence of food insecurity increases as the income-to-needs ratio decreases (
28,
30-
33). Findings from the Third National Health and Nutrition Examination Survey (NHANES III) also confirmed this relationship (
34). A study in Canada found evidence that improvements in family income and employment reduce household food insecurity, indicating the potential for income- and employment-based policy strategies to strengthen household food security for low-income families (
35). Another study conducted in southern Ethiopia documented that income inequality exacerbates the food insecurity of families, with food-insecure households having significantly higher income inequality (Gini coefficient) than those who were food-secure (
36). In Iran, Majdizadeh et al. showed a significant positive relationship between poverty and food insecurity in children aged 2 - 5 years (
37). Moreover, a large sample study in Tehran identified economic status as the key determinant of food security, with approximately 63% of the poorest families being food insecure (
25). Destitution affects the amount and quality of food each family member consumes, and when family income declines, food insecurity intensifies. Parents' education and employment, particularly the head of the household, can contribute to improving food security by increasing household income levels.
Research on the association between food insecurity and undernutrition complications in children has produced mixed results. In the present study, statistically significant and negative correlations were observed between household food insecurity and type of weight (underweight, normal, and overweight) among children aged 2 - 5 years old. Our findings are consistent with previous studies that demonstrated a significant relationship between food insecurity and underweight in children (
16,
38-
43). Previously, in Iran, Abdurahman et al. also found that household food insecurity was significantly predictive of underweight among children aged 24 - 59 months (
44). Hasan et al. showed that household food insecurity increases the risk of different forms of undernutrition, including underweight and wasting, among children under the age of 5 years in Bangladesh (
45). In Colombia, Hackett et al. reported that food-insecure preschool children were three times as likely to be underweight as food-secure children (
4). Several reasons for these relationships have been proposed, including decreased dietary intakes, a reduction in portion size, frequency of meals, and dietary variety as consequences of household food insecurity (
1). However, some studies conducted in Nepal (
46) and the United States (
47) reported that either household or child food insecurity was not related to underweight in children aged 6 to 23 months and less than 4 years, respectively.
In the present study, household food insecurity couldn’t predict the risk of stunting among children aged 2 - 5 years old. Our findings are in line with the findings of some previous studies. A study in Colombia showed stunting had no association with food insecurity among preschool children (
4). Drennen et al. also reported similar findings in children under the age of 4 years in the United States (
47). Another study on children under 5 years in Ethiopia showed that food insecurity had an association with being underweight, but not with stunting and wasting (
48). The negative association between household food insecurity and type of weight and the lack of relationship between food insecurity and child stunting in our study may suggest that the households’ short-term experience of food insecurity within 30 days before the survey was not enough to cause chronic malnutrition and stunting in children. Underweight is more affected by recent nutritional status. In other words, a reduction in the child’s weight, generally seen as a rapid response to inadequate energy intake, is thought to precede decreases in height. Linear growth occurs much slower than weight gain in children, and stunting may be associated with prolonged micronutrient (especially calcium, zinc, iodine, vitamin D, vitamin A, etc.) or macronutrient (especially protein) deficiency. Additionally, the rate of height growth in children is affected by other factors such as birth length and genetic potential (
49,
50).
Conversely, the results of a study by Majdizadeh et al. in Hamedan City, Iran, showed that food insecurity was significantly related to the Z-score for height-for-age among 2- to 5-year-old urban and rural children (
37). Tiwari et al. also revealed a strong association between household food insecurity and stunting and severe stunting among children under the age of 5 and 2 years, respectively (
51). In Pakistan, families that experienced food insecurity with hunger were three times as likely to have a stunted child (
52).
Overall, the controversial findings achieved in different investigations appear to be partly due to different modules used to measure household food insecurity, criteria used to determine children’s growth status, studies’ sample sizes and age groups, and non-nutritional factors.
5.1. Limitation and Recommendation
Our study has some limitations. First, the cross-sectional design of the study did not allow us to examine the causality between household food insecurity and complications of undernutrition in children. Second, the use of different modules for measuring food insecurity and criteria for child nutritional status in various studies presents a major gap in the comparability of these findings. Third, we didn’t assess the wasting index, an important complication of undernutrition that refers to low weight for height. Finally, the small sample size is another limitation of our study that should be considered in future research.
5.2. Conclusions
In the current study, we illustrate that Iranian families with the lowest income had the highest food insecurity scores. Household food insecurity was negatively correlated with the type of weight among children aged 2 - 5 years old, while it was not associated with stunting. Designing and implementing interventions to increase family income and food security by policymakers may lead to improvements in indices of undernutrition in children.