OBJECTIVE: To assess the bioavailability of calcium, iron and zinc in vegetarian and omnivorous meals served in the university restaurant of the Universidade de Brasília. METHODS: Three samples of each meal were collected during 5 days to determine the concentration of phytate. Calcium, iron and zinc contents were estimated by using food composition tables. The molar ratio between phytic acid and the dietary mineral was used as a criterion to evaluate mineral bioavailability. RESULTS: The mean concentrations of phytate, calcium and iron were significantly higher in the vegetarian meal (p=0.0002; p=0.0015 e p=0.0227, respectively), while zinc concentration was higher in the omnivorous meal (p=0.0205). Both meals presented molar ratios of phytate to calcium and phytate to iron below the critical values (1.56 and 14, respectively) suggesting that phytate in these meals should not impair calcium and iron bioavailability. The molar ratio of phytic acid to zinc in the vegetarian meal was 9.4, while in the omnivorous meal it was 4.3, characterizing them as medium and high bioavailability meals for zinc, respectively. Beans and soy were the highest sources of phytate in both meals. CONCLUSION: Due to the calcium and iron contents in both meals served in the university restaurant of the Universidade de Brasília, phytate content should not induce calcium and iron deficiency in individuals that consume these meals daily. However, given the low zinc content in the meals, phytate content may represent a risk for the development of zinc deficiency, especially in vegetarian men.
vegetarian; omnivorous; biological availability; phytic acid; minerals; bean
