The authors assessed in 53 adolescent lactoovovegetarians (students aged 15-18 years) with a mean period of 3.2 years on the vegetarian diet as compared with a group of 55 omnivores (on a mixed diet) the plasma levels of iron, calcium and zinc. In the group on the vegetarian diet significantly lower levels of all mentioned nutrients were recorded with a higher prevalence of subjects with negative values as compared with omnivores (iron 20.7% vs. 0%, calcium 28.3% vs.7.3%, zinc 11.3% vs. 1.8%). The iron and zinc intake were higher in vegetarians, the calcium intake equal, but in all nutrients there was a higher ratio of intake from plant sources in vegetarians. From comparison of intake values and plasma values it is apparent that in subjects on a vegetarian diet the cause of the reduced serum levels is inhibited absorption due to the constituents of the vegetable diet (phytic acid, oxalacetic acid, dietary fibre) the higher consumption of cereals, pulses and vegetables.

        Key words: adolescents - vegetarians - omnivores - iron - calcium - zinc - intake - serum levels