Background/Aim: In Poland, vegetarian diets are becoming more and more popular. The aim of this study was to examine the effect of iron intake on iron status in vegetarian children. Methods: Dietary iron intake, iron food sources, blood count, serum iron, ferritin level and total iron-binding capacity were estimated in two groups of children, namely vegetarians (n = 22) and omnivores (n = 18) of both sexes, aged from 2 to 18 years. Seven-day food records were used to assess their diet. Results: Dietary iron intake in vegetarians and omnivores was low (up to 65.0 and 60.1% of the recommended dietary allowance). A significantly higher intake of vitamin C was observed in vegetarians compared with omnivores (p = 0.019). The main sources of iron in vegetarians were cereal products, followed by vegetables and mushroom products, then fruit. The prevalence of iron deficiency (ID) was higher in the vegetarian group (p = 0.023). The serum ferritin level and mean corpuscular volume in the vegetarians were also lower than in the omnivores (p = 0.01 and p = 0.014, respectively). Conclusions: Children who follow a vegetarian diet may suffer from ID in spite of having a high vitamin C intake. This indicates the need to introduce dietary education and iron status monitoring.

Despite negligible differences in serum immunoglobulin levels between vegetarian and omnivore children, the impact of several nutrient intakes on IgM and IgG levels differed between groups. Low iron status in vegetarian children can lead to decreased immunoglobulin levels.