Number of food items as an indicator of nutrient intake

Abstract

Total food duplicates for 24 hours were collected from farmers in Japan, once in 1977–1981 (109 subjects) and then in 1991–1992 (72 subjects). Nutrients (including energy, protein, fat, some minerals, and several vitamins) in each food item in the food duplicate were estimated taking advantage of the values given in the Standard Tables of Food Compositions in Japan. The number of the food items in each food duplicate was counted excluding duplication. Analyses demonstrated that the daily nutrient intake (especially that of energy, protein and vitamin B1) has a significant association with the number of items of food taken a day, that the daily intake of most nutrients is sufficient when 30 food items were taken a day, but that the sufficient supply of calcium and iron needs an intake of more than 30 food items.