Assessment of zinc, manganese, copper, and magnesium intake levels in Koreans using the Korean Total Diet Study.

This study evaluated zinc, manganese, copper, and magnesium intake levels in Koreans using the Korean Total Diet Study, targeting 92-93% of the Korean diet. Representative foods were collected from 9 cities, resulting in 1344-1368 samples. Results showed adequate intake for most minerals, but high proportions of adults and adolescents didn't meet recommended levels. Infants had high levels of zinc and manganese intake, posing possible health concerns. This is the first comprehensive assessment of these nutrients in Korea and is significant for considering all age groups, including infants, by analyzing nutrient content for table-ready (cooked) samples of foods. It is hoped that the Korean Total Diet Survey will be expanded to assess a wider range of nutrients for better nutrient intake assessment in Korea. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01394-y.

Iodine intake from brown seaweed and the related nutritional risk assessment in Koreans.

BACKGROUND/OBJECTIVES: Although iodine is essential for thyroid hormone production and controls many metabolic processes, there are few reports on the iodine intake of the population because of the scarcity of information on the iodine content in food. This study estimated the iodine intake of Koreans from brown seaweed, the major source of iodine in nature. SUBJECTS/METHODS: The dietary intake data from the recent Korea National Health and Nutrition Examination Survey (2016-2021) and the iodine content in brown seaweed were used for the estimation. Nationwide brown seaweed samples were collected and prepared using the representative preparation/cooking methods in the Koreans' diet before iodine analysis by alkaline digestion followed by inductively coupled plasma mass spectrometry. RESULTS: The mean (± SE) iodine intake from sea mustard was 96.01 ± 2.36 µg/day in the Korean population. Although the iodine content in kelp was approximately seven times higher than that in sea mustard, the mean iodine intake from kelp (except broth) was similar to that of sea mustard, 115.58 ± 7.71 µg/day, whereas that from kelp broth was 347.57 ± 10.03 µg/day. The overall mean iodine intake from brown seaweed was 559.16 ± 13.15 µg/day, well over the Recommended Nutrient Intake of iodine for Koreans. Nevertheless, the median intake was zero because only 37.6% of the population consumed brown seaweed on the survey date, suggesting that Koreans do not consume brown seaweed daily. CONCLUSION: The distribution of the usual intake of iodine from brown seaweed in Koreans would be much tighter, resulting in a lower proportion of people exceeding the tolerable upper intake levels and possibly a lower mean intake than this study presented. Further study evaluating the iodine nutriture of Koreans based on the usual intake is warranted. Nevertheless, this study adds to the few reports on the iodine nutriture of Koreans.