Abstract
OBJECTIVES: Total Diet Study (TDS) determines levels of the analytes in foods as they would be consumed (table-ready). This is particularly important for estimating dietary intake of nutrients, level of which may be changed as a result of preparation. Hence, we attempted to compare some nutrient intakes estimated from food composition databases (FCD) in nutrition survey (NS) and from real-time food analysis data in TDS based on The Korea National Health and Nutrition Examination Survey (KNHANES) 2013–2016. METHODS: We established a nationwide representative dietary intake data set of 4 years from KNHANES 2013–2016. Based on the type of dishes (prepared foods) consumed, 224 pairs of ‘food X cooking methods’ were identified covering more than 92.7% of total food intake of Koreans for calcium, iron and zinc analysis using ICP–MS and ICP–AES. RESULTS: Mean calcium intake was 460.6 mg/person/day in TDS vs 487.3 mg/person/day in NS. In TDS, the food groups contribute mostly to calcium were milk & dairy (29.6%), vegetables (24.4%), and grains & cereals (12.5%) while they were vegetables (25.6%), milk & dairy (25.3%), and fishes & shellfishes (13.8%) in NS. Calcium intake from milk accounted for 20.8% of total intake in TDS vs 14.3% in NS. Similarly, only 10 foods were necessary to cover half of calcium intake in TDS vs more than 15 in NS. Iron intake was estimated to be 7.80 mg/person/day in TDS vs 16.9 mg/person/day in NS. The major food groups contributing to iron were vegetables (20.3%), grains & cereals (17.9%), and meats & their products (16.7%) in TDS. On the other hand, they were quite different in NS: grains & cereals (25.3%), vegetables (22.6%), and meats & their products (11.5%). While top iron source was eggs accounting for 7.9% in TDS, it was rice (11.6%) in NS. Although zinc intake of Koreans has never been officially announced from KNHANES due to incomplete database, we attempted to estimate zinc intake in TDS. Mean zinc intake was 10.16 mg/person/day and major food groups contributing to zinc were grains & cereals (37.2%) and meats & their products (26.0%). Top zinc source was rice (25.2%) and 5 foods were enough to cover half of zinc intake. CONCLUSIONS: While mean mineral intakes of Koreans estimated by 2 methods were quite comparable, more frequent revision of FCD is warranted for staple foods and well-known sources of each nutrient. FUNDING SOURCES: This research was supported by a grant from Ministry of Food and Drug Safety in 2018 (Total Diet Study for Food Standard & Specifications in Korea).