ABSTRACT
BACKGROUND AND OBJECTIVES: Iodine is essential for thyroid hormone production and the iodine intake of Koreans is high. Few studies have examined the association between iodine intake and thyroid disease in the Korean population due to the lack of an iodine database. Therefore, this study established an iodine database, evaluated iodine intake levels, and explored the association between iodine intake and thyroid disease. MATERIALS AND METHODS: We obtained data for 9998 subjects who had both biochemical and dietary data from the 2007-2009 Korea National Health and Nutrition Examination Survey. RESULTS: An iodine database was established for 667 food items. The median iodine intake in the population was 375.4 microg per day. The iodine contribution by food group was 65.6% from seaweed, 18.0% from salted vegetables, and 4.8% from fish. When subjects were divided into five groups across quintiles of iodine intake per 1000 kcal, excluding extreme subjects who consumed above the upper limit, age, sex, income, education, drinking, and smoking differed across the groups. While the energy and fat intakes decreased, other nutrients increased across the quintile groups. The consumption of seaweeds, fish, eggs, and salted vegetables increased across the quintile groups. After adjusting for all potential confounding variables, the odds ratio for thyroid disease in the highest quintile was 1.63 compared to that in the lowest quintile (p for trend=0.0352). CONCLUSION: The iodine intake of the Korean population is high, with high consumption of seaweeds, salted vegetables, and fish positively associated with thyroid disease.
Subject(s)
Adult , Humans , Drinking , Education , Eggs , Iodine , Korea , Nutrition Surveys , Odds Ratio , Ovum , Seaweed , Smoke , Smoking , Thyroid Diseases , Thyroid Gland , VegetablesABSTRACT
PURPOSE: The prevalence of metabolic syndrome has increased in both the adult population and in adolescents. How-ever, few studies have been conducted for adolescents. The aim of this study was to examine the association of metabolic syndrome and its risk factors with high carbohydrate diet and high fat diet using data from the Korea National Health and Nutrition Examination Survey (1998-2009). METHODS: Using the Acceptable Macronutrient Distribution Range for Korean Dietary Reference Intakes, subjects whose energy intake from carbohydrate was greater than 70% and from fat was less than 15% were classified as the 'High-carbohydrate & low-fat diet (HCLF)' group and subjects whose energy intake from carbohydrate was less than 60% and from fat was 25% or more were classified as the 'Low-carbohydrate & high-fat Diet (LCHF)' group. Among 5,931 eligible subjects, HCLF included 853 subjects and LCHF included 1,084 subjects. RESULTS: The mean age in both groups was 14 years and significant difference in age, BMI, sex, physical activity, and household income was observed between the HCLF and LCHF groups. Regarding the energy intake compared to Estimated Energy Re-quirement, the HCLF group met 79.0% and the LCHF group met 100.3%. Regarding nutrient intake per 1,000 kcal, carbo-hydrate, iron, potassium, and vitamin C intake in the HCLF group were significantly higher, but protein, fat, calcium, phos-phorus, vitamin A, thiamin, riboflavin, and niacin intakes were significantly lower in the HCLF group compared to the LCHF group. After adjusting for age, sex, BMI, study year, household income, physical activity, and energy intake, the serum tri-glycerides level and systolic blood pressure were slightly higher, while the serum HDL-cholesterol level was significantly lower in HCLF than LCHF. The odds ratio of metabolic syndrome did not differ significantly between HCLF and LCHF. CONCLUSION: Our findings indicate an association of a high carbohydrate diet with increased risks for metabolic syndrome components. Conduct of future studies would be necessary in order to explore the underlying mechanism and to confirm our findings in a prospective study.