The iron content in vegetarian and omnivorous diets was quantified by both chemical analysis and by calculation from food composition tables. The bioavailability of iron from these diets was estimated on a meal basis of the amount of heme iron，non-heme iron and enhancing factors including ascorbic acid，meat，fish and poultry. Foods from vegetarian and omnivorous diets were collected from the student dining service in Yuan-Guan Buddhist College，Chungli，and the National Defense Medical School，Taipei，respectively. Three servings of every dish provided at breakfast，lunch and dinner were collected，weighed，combined，freeze-dried，ground up，and used for chemical analysis. By calculation，the iron supply averaged 19. 8mg/day and 17. 5mg/day，and the iron density was 7. 7 and 7. 5mg/1000kcal，in omnivorous and vegetarian diets, respectively. By chemical analysis, the iron supply was 16. 1 and 11. 6mg/day，and the iron density was 6. 2 and 5. 0mg/1000kcal in omnivorous and vegetarian diets, respectively. Non-heme iron was the major dietary iron form. Correlation between calculated and analyzed values was significant for both types of diets, but in the vegetarian diets, the analyzed value was significantly less than the calculated value. Estimated amount of bioavailable iron was 0. 65mg/1000kcal from the omnivorous diets, and it was 0. 39 and 0. 22mg/day in the vegetarian diets with or without the vitamin C effect，respectively. The estimated bioavailability was 8. 4% in the omnivorous diet，and it was 5. 3% and 3. 0% in the vegetarian diets with and without the vitamin C effect，respectively. The vegetarian diets were low in both iron content and availability，and may not provide adequate iron for women of child-bearing age.
