Particulate matters (PM2.5, PM10) and the risk of depression among middle-aged and older population: analysis of the Korean Longitudinal Study of Aging (KLoSA), 2016-2020 in South Korea.

BACKGROUND: There is a growing concern that particulate matter (PM) such as PM2.5 and PM10 has contributed to exacerbating psychological disorders, particularly depression. However, little is known about the roles of these air pollutants on depression in elderly. Therefore, this study aimed to examine the association between PM2.5 and PM10, and depression in the elderly population in South Korea. METHODS: We used panel survey data, the Korean Longitudinal Study of Aging (KLoSA), administered by the Labor Institute during the study period of 2016, 2018, and 2020 covering 217 districts in South Korea (n = 7674). Annual district-specific PM2.5 and PM10 concentrations were calculated for the study period from the monthly prediction concentrations produced by a machine-learning-based ensemble model (cross-validated R2: 0.87), then linked to the people matching with year and their residential district. We constructed a generalized estimating equation (GEE) model with a logit link to identify the associations between each of the long-term PM2.5 and PM10 exposures and depression (CES-D 10) after adjusting for individual and regional factors as confounders. RESULTS: In single-pollutant models, we found that long-term 10 [Formula: see text] increments in PM2.5 (OR 1.36, 95% CI 1.20-1.56) and PM10 (OR 1.19, 95% CI 1.10-1.29) were associated with an increased risk of depression in the elderly. Associations were consistent after adjusting for other air pollutants (NO2 and O3) in two-pollutant models. In addition, the impacts substantially differed by regions grouped by the tertile of the population density, for which the risks of particulate matters on depression were substantial in the middle- or high-population-density areas in contrast to the low-population-density areas. CONCLUSIONS: Long-term exposure to PM2.5 and PM10 was associated with a higher risk of developing depression in elderly people. The impact was modified by the population density level of the region where they reside.

Dietary patterns derived by reduced rank regression are associated with lipid disorders among Korean adults: a cross-sectional analysis.

BACKGROUND: Lipid disorders are a potent risk factor for cardiovascular diseases. Moreover, the intake of dietary fatty acids has been closely related to blood lipid levels. Therefore, this cross-sectional study examined the associations between dietary patterns related to fatty acid intake and lipid disorders in Korean adults. METHODS: From the 2013-2019 Korea National Health and Nutrition Examination Surveys data, 8399 men and 11404 women (aged ≥ 19 years) were selected. Reduced rank regression was employed to identify dietary patterns from 26 food groups, aiming to explain the maximum variation in the intake of saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), omega-3 fatty acids, and the PUFA/SFA ratio. Associations of quintiles (Q) of dietary pattern scores with lipid disorders were examined using multiple logistic regression stratified by sex. RESULTS: Three dietary patterns were identified: dietary pattern 1 showed positive factor loadings for vegetable oils, seasonings, legumes, nuts, and fish; dietary pattern 2 was high in consumption of red meat, bread and snacks, and milk and dairy products; and dietary pattern 3 was rich in fish and milk and dairy products. In men, dietary pattern 3 was inversely associated with elevated triglycerides (Q5 vs. Q1: odds ratio [OR] = 0.82, 95% confidence interval [CI] = 0.69-0.97, P-trend = 0.008). In women, dietary pattern 2 was positively associated with elevated total cholesterol (OR = 1.31, 95% CI = 1.12-1.52, P-trend < 0.001) but inversely associated with low HDL-cholesterol (OR = 0.70, 95% CI = 0.59-0.83, P-trend < 0.001). CONCLUSION: In this study, dietary patterns explaining the intake of various types of fatty acids were differentially associated with lipid disorders in Korean adults. Dietary pattern characterized by higher intakes of red meat, bread and snacks and milk and dairy products were positively associated with elevated total cholesterol, whereas dietary pattern rich in fish consumption showed an inverse association with elevated triglycerides. These findings could be instrumental in developing dietary guidelines and strategies for preventing and managing lipid disorders in this population.

A randomized, double-blind, placebo-controlled study on immune improvement effects of ethanolic extract of Echinacea purpurea (L.) Moench in Korean adults.

Echinacea purpurea (L.) Moench (EP), a medicinal plant native to North America, is now cultivated in various regions including Europe. With increasing popularity of Echinacea in Korea recently, a human clinical trial was conducted to evaluate immune-enhancing efficacy and safety of EP 60% ethanolic extract (EPE) in Koreans. Eighty volunteers were recruited for this randomized, double-blind, placebo-controlled clinical trial. They were randomly divided into two groups and given either a daily dose of 200 mg of EPE or a placebo. All participants underwent testing for Natural Killer (NK) cell cytotoxic activity, serum cytokine levels (IL-2, IL-6, IL-10, IL-12, IFN-γ, TNF-α), Wisconsin Upper Respiratory Symptom Survey-21 (WURSS-21), and Multidimensional Fatigue Scale (MFS) during this study to assess changes in outcomes. After 8 weeks of EPE consumption, a significant increase in NK cell cytotoxic activity compared to the placebo was observed. Additionally, serum cytokine levels of IL-2, IFN-γ, and TNF-α also significantly increased following EPE consumption. However, no significant changes were observed in WURSS-21 and MFS before and after EPE consumption. Throughout the 8-week study period, no adverse reactions were reported in relation to EPE consumption, and there were no clinically significant changes in diagnostic laboratory tests or vital signs in the EPE group. These results indicate that consumption of EPE could lead to immune improvement without any adverse effects. This clinical trial was the first to demonstrate beneficial effects of EPE consumption on immunity in Korean adults.

Decadal Trends in Physical Activity Adherence Among Korean Older Adults: An Analysis of National Survey of Older Korean Data, 2011-2020.

BACKGROUND/OBJECTIVES: This study investigated adherence to physical activity (PA) guidelines and associated sociodemographic factors among older Koreans from 2011 to 2020. METHODS: Utilizing four public data sets from the National Survey of Older Koreans, the study included the data on 40,993 older adults 65 years and older in South Korea, collected between 2011 and 2020. Adherence to PA guidelines and sociodemographic factors were assessed through self-reported questionnaires. The data were analyzed using a two-way analysis of variance and post hoc tests. RESULTS: Overall adherence increased from 39.1% in 2011 to 48.2% in 2017, then decreased to 37.6% in 2020 (p < .001). Men had higher adherence than women (p < .001). Age-related adherence peaked in the young-older group (65-74 years old) and was lowest in the oldest-old group (85+ years old) (p < .001). Marital status, education, and income were also significantly related to PA adherence (p < .001) across the years. CONCLUSION: Although continuous increase in adherence to PA among Koreans 65 years and older was observed, the decline in PA levels during the COVID era underscored the need for targeted interventions and well-informed health care policies to address demographic challenges. Still, considering that data were collected during the recommended social distancing period, a cautions interpretation of these findings is warranted. Significance/Implications: Health policies aiming to improve adherence to PA guidelines should prioritize Korean older adults who are female, belong to the oldest-old group, are single, and have low education and income levels, with the goal of enhancing health equity.

Prognostic value of resting heart rate in predicting undiagnosed diabetes in adults: Korean National Health and Nutrition Examination Survey 2008-2018.

BACKGROUND AND AIM: Although resting heart rate (RHR) is associated with prevalence and incidence of diabetes, whether it is associated with undiagnosed diabetes is still unclear. We aimed to investigate whether the RHR is associated with the prevalence of undiagnosed diabetes in a large Korean national dataset. METHODS AND RESULTS: The Korean National Health and Nutrition Examination Survey data from 2008 to 2018 were used. After screening, 51,637 participants were included in this study. The odds ratios and 95% confidence intervals (CIs) for undiagnosed diabetes were calculated using multivariable-adjusted logistic regression analyses. Analyses showed that participants with a RHR of ≥90 bpm showed a 4.00- (95% CI: 2.77-5.77) and 3.21-times (95% CI: 2.01-5.14) higher prevalence of undiagnosed diabetes for men and women, respectively, than those with a RHR of <60 bpm. The linear dose-response analyses showed that each 10-bpm increment in RHR was associated with a 1.39- (95% CI: 1.32-1.48) and 1.28-times (95% CI: 1.19-1.37) higher prevalence of undiagnosed diabetes for men and women, respectively. In the stratified analyses, the positive association between RHR and the prevalence of undiagnosed diabetes was tended to be stronger among those who were younger (age: <40 years) and lean (BMI: <23 kg/m2). CONCLUSIONS: Elevated RHR was significantly associated with a higher prevalence of undiagnosed diabetes in Korean men and women, independent of demographic, lifestyle, and medical factors. Accordingly, the value of RHR as a clinical indicator and health marker, especially in reducing the prevalence of undiagnosed diabetes, is suggestible.

Association of main meal frequency and skipping with metabolic syndrome in Korean adults: a cross-sectional study.

BACKGROUND: Reduced meal frequency can increase the risk of metabolic syndrome (MetS). However, limited studies have examined the association between meal frequency and skipping meals with MetS. This study aims to analyze the association between main meal frequency and meal skipping with MetS in Korean adults aged ≥ 19 years. METHODS: In this study, we included data from 22,699 Korean adult participants from the 2016-2020 Korea National Health and Nutrition Examination Survey (KNHANES). The 24-h dietary recall method was used to classify the participants into three groups based on main meal frequency (one, two, or three meals per day) and seven groups based on the type of main meal they skipped. Multivariable logistic regression analysis was conducted to determine the association between main meal frequency and the types of main meals skipped with the odds of MetS and its associated components. Appropriate estimates were accounted for using sampling weights, stratification, and clustering. RESULTS: The prevalence of MetS in the study population was 33.8%. The average age of the participants was 47.2 years with 42.6% being men, and 57.4% being women. Men who consumed two meals per day had higher odds of MetS than those who consumed three meals per day (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.01-1.33). Women who consumed two meals per day, and skipped breakfast had increased odds of having elevated fasting blood glucose levels (OR 1.18, 95% CI 1.02-1.35), and elevated triglycerides (OR 1.19, 95% CI 1.02-1.39). However, women who skipped dinner had reduced odds of having elevated fasting blood glucose levels (OR 0.74, 95% CI 0.58-0.94). CONCLUSIONS: Our findings suggest that meal frequency and the type of main meal skipped may be associated with MetS and emphasize the importance of consuming breakfast to prevent MetS.

E-health literacy and associated factors among Korean adults during the COVID-19 pandemic: age-group differences.

The purpose of this study was to compare the mean scores of e-health literacy, health information, social relationships, and psychological status between younger, middle-aged, and older Korean adults during the COVID-19 pandemic and to identify the factors associated with e-health literacy as well as the moderating effect of age on the association between health information factors and e-health literacy. We used a cross-sectional survey of 2400 Korean adults aged 20 years or older residing in Seoul. Descriptive statistics, ANOVA, chi-square test, and hierarchical multiple regression analyses were used to analyze the data. Findings demonstrated an age-group difference in the mean score of e-health literacy with the older group having lower e-health literacy than the other groups. Health information, social support, and COVID-19-related anxiety were associated with e-health literacy and a moderating effect of age on the association between sources of health information and e-health literacy was also identified among the three age subgroups. This study emphasizes the importance of identifying e-health-related risk factors leading to health disparities between age groups.

Interactions between Bitter Taste Receptor Gene Variants and Dietary Intake Are Associated with the Incidence of Type 2 Diabetes Mellitus in Middle-Aged and Older Korean Adults.

The relationship between the variants of bitter taste receptor gene TAS2R4, dietary intake, and incidence of type 2 diabetes mellitus (T2DM) remains unclear. Hence, we aimed to examine the association of TAS2R4 rs2233998 variants with T2DM incidence in middle-aged and older Korean adults to understand if their association was modulated by dietary intake. Data of the Ansan-Ansung cohort from the Korean Genome and Epidemiology Study were used in this study. A total of 4552 Korean adults aged 40-69 years with no history of T2DM or cancer at baseline were followed-up for 16 years. Dietary intake was assessed using a 103-item food frequency questionnaire, and new T2DM cases were defined based on the World Health Organization and International Diabetes Federation criteria. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for T2DM incidence. During the mean follow-up period of 11.97 years, 1082 (23.77%) new T2DM cases were identified. Women carrying the TT genotype of TAS2R4 rs2233998 exhibited 1.48 times higher incidence of T2DM (HR: 1.48; 95 CI: 1.13-1.93) than those carrying the CC genotype. TAS2R4 rs2233998 variants were positively associated with the incidence of T2DM among Korean women with high intakes of carbohydrates or sugars and low intakes of fruits or vegetables. TT carrier women in the highest tertile of carbohydrate or sugar intake exhibited an increased incidence of T2DM (HR: 2.08, 95% CI: 1.33-3.27 for carbohydrates; HR: 2.31, 95% CI: 1.53-3.51 for sugars) than CC carrier women. Women carrying the TT genotype in the lowest tertile exhibited an increased incidence of T2DM (HR: 1.55, 95% CI: 1.02-2.37 for vegetables; HR: 1.62, 95% CI: 1.06-2.48 for fruits) than women carrying the CC genotype in the highest tertile of vegetable or fruit consumption. However, no association was observed between TAS2R4 rs2233998 variants and dietary intake with T2DM incidence in Korean men. Our findings suggest that variants of TAS2R4 rs2233998 are associated with T2DM incidence, and their associations are strengthened by excessive intake of carbohydrates or sugars and inadequate intake of fruits or vegetables. Diet encompassing optimal intake of carbohydrates or sugars and high intake of fruits or vegetables may minimize the risk of developing T2DM.

Trends in intake and sources of dietary protein in Korean adults, 1998-2018.

Although a decrease in carbohydrate intake and an increase in fat intake among Koreans have been reported, investigations of changes in protein intake have been limited. Thus, this study aimed to explore trends in the dietary intake of total, plant and animal proteins overall and by socio-demographic subgroups in Korea over the past two decades. A total of 78 716 Korean adults aged ≥ 19 years who participated in the seven survey cycles of the Korea National Health and Nutrition Examination Survey 1998-2018 were included. Dietary protein intake, overall and by source, was calculated using a single 24-h dietary recall data. Changes in dietary protein over 20 years were estimated using multiple linear regression analysis after adjusting for potential covariates. For total protein intake, a significant decrease was reported from 1998 to 2016-2018 (P for trendlinearity < 0·001), whereas an increasing trend was observed from 2007-2009 to 2016-2018 (P for trendlinearity < 0·001). In terms of protein intake by source, plant protein intake decreased while animal protein intake increased over the past two decades, indicating steeper trends during the recent decade (P for trendlinearity < 0·001). These trends were more pronounced among younger adults and those with higher household income and education levels. These findings suggest that continuous monitoring of dietary protein intake overall and by source (plant v. animal) across socio-demographic group is needed.

Diets high in glycemic index and glycemic load are associated with an increased risk of metabolic syndrome among Korean women.

BACKGROUND AND AIMS: Accurate estimation of the glycemic index (GI) and glycemic load (GL) of diets is essential when assessing health implications of dietary GI and GL. The present study aimed to estimate dietary GI and GL utilizing the updated GI tables with a large number of new, reliable GI values and assess their associations with metabolic syndrome among Korean adults. METHODS AND RESULTS: We analyzed data from 3317 men and 6191 women for this cross-sectional study. Dietary intake was assessed with a validated food frequency questionnaire. Metabolic syndrome and its components were defined based on the harmonized criteria with Korean-specific cutoffs for waist circumference. Multivariate logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Compared with women in the lowest quintiles of energy-adjusted dietary GI and GL, women in the highest quintiles had significantly greater risks of metabolic syndrome (GI, OR = 1.56, 95% CI = 1.18-2.06; GL, OR = 1.80, 95% CI = 1.27-2.57), elevated blood pressure, reduced high-density lipoprotein cholesterol (HDL-C, both GI and GL), elevated triglycerides (GI only), elevated waist circumference, and elevated fasting glucose (GL only). Among men, no significant association was noted except for a higher risk of reduced HDL-C (OR = 1.59, 95% CI = 1.01-2.29) in the highest quintile of energy-adjusted dietary GI than in the lowest quintile. CONCLUSION: Our findings suggest that dietary GI and GL are positively associated with metabolic syndrome risk among women, but not men, in Korea.

The Role of Social Networks on Depressive Symptoms: A Comparison of Older Koreans in Three Geographic Areas.

The purpose of this study was to examine the correlates of depressive symptoms among older Korean adults in three geographic locations with varying densities of the Korean population: mainland Korea (mostly Koreans), New York metropolitan area (high Korean density), and west central Florida (low Korean density). The study focused on the role of family and friend networks. Data were drawn from three sources: (1) a multistage national sample of Koreans in South Korea (n = 403); (2) a survey conducted in the western/central Florida area that used a variety of culturally sensitive sampling strategies (n = 672); and (3) a survey in the New York metropolitan area (n = 420) that replicated the Florida study. For those living in Korea, living alone and lower perceived financial status were independently associated with higher levels of depressive symptoms. For the New York and Florida samples, fair or poor self-rating of health, lower levels of acculturation, and weaker ties with family were related to higher levels of depressive symptoms. Similar to the older Korean sample, lower perceived financial status was linked with greater depressive symptoms in the New York sample. The overall results suggest that it is important to consider the interplay of the social network, personal, and cultural resources when working with older adults in diverse contexts. Intervention efforts should address mental health issues tailored to cultural and social settings.

The association between urinary bisphenol A levels and nonalcoholic fatty liver disease in Korean adults: Korean National Environmental Health Survey (KoNEHS) 2015-2017.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is becoming a global health problem. Bisphenol A (BPA), one of most widely used environmental chemicals, is suspected to be a contributor to the development NAFLD. This study was performed to examine the relationship between human BPA levels and risk of NAFLD. METHODS: The data (n = 3476 adults: 1474 men and 2002 women) used in this study were obtained from the Korean National Environmental Health Survey III (2015-2017). BPA levels were measured in urine samples. NAFLD was defined using hepatic steatosis index after exclusion of other causes of hepatic diseases. RESULTS: There was a significant linear relationship between the elevated urinary BPA concentrations and risk of NAFLD. In a univariate analysis, odds ratio (OR) of the highest quartile of urinary BPA level was 1.47 [95% confidence interval (CI) 1.11-1.94] compared to the lowest quartile. After adjusted with covariates, the ORs for NAFLD in the third and fourth quartiles were 1.31 [95% CI 1.03-1.67] and 1.32 [95% CI 1.03-1.70], respectively. CONCLUSIONS: Urinary BPA levels are positively associated with the risk of NAFLD in adults. Further experimental studies are needed to understand the molecular mechanisms of BPA on NAFLD prevalence.

Health Literacy in Korean Adults and Korean American Immigrants: Implications for Achieving Health Equity.

Health literacy is necessary to understand health information and make appropriate decisions regarding one's health. This study aims to investigate (1) the health literacy level of Korean citizens and Korean American (KA) immigrants in the United States and (2) factors that influence health literacy across three age groups. A quota sampling method was used to collect cross-sectional survey data from 404 Korean participants and 404 KA immigrants. Andersen's behavioral model was used as the theoretical framework for this study. Overall, Korean participants had a higher mean score on health literacy than did the KA immigrants. Only one of predisposing and enabling factors were significant variables influencing health literacy in KA immigrants, while several predisposing, enabling and need factors were significantly associated with health literacy in Korean adults. Our findings indicate that both countries need to have a community-based health literacy educational program that is tailored to each age group.

Non-exercise based estimation of cardiorespiratory fitness is inversely associated with metabolic syndrome in a representative sample of Korean adults.

BACKGROUND: This study investigated the association between non-exercise based estimation of cardiorespiratory fitness (eCRF) and metabolic syndrome (Mets) in Korean adults aged 18 years and older (13,400 women and 9885 men). METHODS: Data from the 2008 and 2011 Korea National Health and Nutrition Examination Surveys IV and V in South Korea were analyzed. eCRF was assessed with a previously validated procedure. Participants were classified into 5 categories from the lowest quantile to the highest quantile based on individual eCRF distributions. RESULTS: The findings showed an independent and inverse association between eCRF and Mets in women and men separately. Individuals in the highest eCRF category (quantile 5) had a significantly lower prevalence of Mets (14.5 and 14.8% for women and men, respectively) compared with their counterparts (40.4 and 46.4% for women and men, respectively) in the lowest eCRF category (quantile 1), and the association showed a graded response, with the quantiles 2, 3, and 4 also significantly associated with a lower prevalence of Mets compared with the quantile 1. Furthermore, the prevalence of Mets in the highest quantile compared with the lowest quantile remained statistically significant in both men (p < 0.05) and women (p < 0.05) even after adjustments for age, body mass index, skeletal muscle index, smoking, heavy drinking, vitamin D, caloric intake, and dietary intakes of carbohydrates, fats, and proteins. CONCLUSION: The findings support a preventive role for eCRF against Mets in Korean adults.

Body mass index and trajectories of cognitive decline among older Korean adults.

Objectives: This study examined the relationship between body mass index (BMI) and trajectories of cognitive decline among older Korean adults.Methods: Participants were a nationally representative sample of 5126 Korean adults aged 60 or older from the Korean Longitudinal Study of Aging (KLoSA: 2006-2014). The main outcome variable, cognitive function, was measured with the Korean Mini-Mental State Examination (K-MMSE). According to the BMI values, respondents were divided into four groups at each wave: underweight (<18.5 kg/m2), healthy weight (18.5-22.9 kg/m2), overweight (23.0-24.9 kg/m2), and obese (≥25.0 kg/m2). Growth curve modeling was used to analyze the relationship of interest.Results: The growth curve modeling revealed that, regardless of BMI values, cognitive functioning declined as participants aged, and the rate of cognitive decline accelerated with age. After adjusting for all covariates, older Korean adults who were underweight displayed steeper declines in cognitive functioning, compared to those with a healthy weight. Conversely, overweight or obese older adults showed a much slower cognitive decline as they aged, after adjusting for covariates.Conclusion: Compared to people with a healthy BMI, people with a low BMI may be at risk for cognitive dysfunction, whereas a high BMI could function as a protective factor for cognitive dysfunction in older adulthood. Future research examining the mechanism for these trajectories are needed. Implications for research and clinical practice are discussed.

A Typology of Social Networks and Its Relationship to Psychological Well-Being in Korean Adults.

The purposes of this study were to (a) develop an empirical typology of the social networks in Korean adults aged 18 years or older and (b) examine the relation of network types on depressive symptoms and satisfaction with life. Data for this study were drawn from the survey with 1,017 community-dwelling adults aged 18 years or older in South Korea representing three life stages: young adults, middle-aged adults, and older adults. Latent profile analysis was conducted based on eight social network-related variables: marital status, living arrangement, number of family confidants, number of friend confidants, frequency of contact with friends using phone or social media, frequency of participation in social groups, frequency of conversation with neighbors, and perceived closeness of family. The identified typologies were then regressed on depressive symptoms and satisfaction with life. A model with four network types was identified as being the most optimal, and the groups were labeled as: diverse-family, diverse-friend, solo-restricted, and coresident-restricted. Regression analyses showed that in comparison with the coresident-restricted group referent, diverse-friend and solo-restricted groups exhibited elevated levels of depressive symptoms; diverse-family and diverse-friend type had higher levels of satisfaction with life. Implications of the study findings were discussed in line with current research and intervention efforts.

Three types of a high-carbohydrate diet are differently associated with cardiometabolic risk factors in Korean adults.

PURPOSE: Although a high-carbohydrate diet typically shows low-fat intake, the prevalence of metabolic abnormalities in Asian countries has increased. We evaluated three types of a high-carbohydrate diet and its association with cardiometabolic risk factors in the Korean adult population. METHODS: A total of 14,438 adults (5813 men and 8625 women) who participated in the 2008-2012 Korea National Health and Nutrition Examination Surveys were selected. Dietary data were obtained by a single 24-h recall method. High-carbohydrate diets were defined using three carbohydrate variables, including total carbohydrate intake, proportion of energy from carbohydrate, and white rice consumption as dietary exposures. Cardiometabolic risk factors included obesity, abdominal obesity, hypercholesterolemia, atherogenic dyslipidemia, impaired fasting glucose, and elevated blood pressure. A multivariate-adjusted logistic regression was performed to examine the associations between high-carbohydrate diets and cardiometabolic risk factors by sex. RESULTS: Three types of high-carbohydrate diets showed different energy intakes and food group consumption when individuals in the highest quintile of each type were compared. In men, intakes of total carbohydrate and white rice were inversely associated with obesity, impaired fasting glucose, and elevated blood pressure and proportion of energy from carbohydrate and white rice consumption were inversely related to hypercholesterolemia. In women, a high consumption of white rice was positively associated with impaired fasting glucose. All three types of high-carbohydrate diets were positively associated with the prevalence of atherogenic dyslipidemia in both sexes. CONCLUSIONS: Three types of high-carbohydrate diets show different associations with cardiometabolic risk factors except for unfavorable effects on atherogenic dyslipidemia.

Trends in total fat and fatty acid intakes and chronic health conditions in Korean adults over 2007-2015.

OBJECTIVE: To investigate trends in total fat and fatty acid intakes and chronic health conditions among Korean adults over nine years between 2007 and 2015. DESIGN: Cross-sectional, observational study using a stratified, multistage probability sampling design at a national level. Intakes of total fat and fatty acids were estimated from 24 h dietary recalls by sex and age groups. Trends of total fat and fatty acid intakes were determined by multiple linear regression after adjusting for covariates. Trends in age-standardized prevalence of obesity, hypercholesterolaemia and hypertriacylglycerolaemia were examined by sex. SETTING: Korea.ParticipantsPopulation data of 47749 healthy adults (aged ≥19 years) derived from the Korea National Health and Nutrition Examination Survey between 2007 and 2015. RESULTS: Over the survey period, daily intakes of energy and total, saturated, monounsaturated, polyunsaturated, n-3 and n-6 fats (grams and percentage of energy (%E)) increased steadily. In all sex and age groups, significant increases were seen in SFA intake from 9·9 g (4·7 %E) to 12·0 g (5·3 %E) and in MUFA intake from 9·9 g (4·6 %E) to 13·3 g (5·8 %E). The prevalence of hypercholesterolaemia increased from 10·7 to 17·9 % over the same period. CONCLUSIONS: In Korean adults, total fat, SFA and other fatty acids have been increasing along with the prevalence of hypercholesterolaemia. This information can help set adequate macronutrient and fatty acid distribution ranges in developing population-specific preventive strategies against diet-related illness.

Consumption Patterns and Importance-Performance Analysis of Home Meal Replacements by Level of Taurine-Related Nutritional Knowledge in Korean Adults.

The purpose of this study was to investigate consumption patterns and perform Importance-Performance Analysis (IPA) of selective attributes of Home Meal Replacement (HMR) products according to taurine-related nutritional knowledge levels in Koreans aged 40-64 years as a basis for developing additional HMR products. The study included 793 adults (297 males and 496 females) who had experience in consuming HMR products and who lived in Seoul and its metropolitan areas, Korea. Data were collected using self-administered questionnaires. Statistical analysis was performed by using the SPSS 18.0 program. The subjects were classified into a high-level group (HG, 467 adults) and low-level group (LG, 326 adults) based on their taurine-related nutritional knowledge scores. Analysis of HMR consumption patterns showed that the frequency of HMR consumption in the HG was one to two times a month in 41.1% of the subjects and once every 3-4 months in 22.7% of the subjects, whereas, in the LG, it was one to two times a month in 39.3% of the subjects and four to six times a month in 24.5% of the subjects. With regarding to the reasons for purchasing HMR products, there was no significant difference between HG and LG (p = 0.089). The IPA analysis of HMR selective attributes included factor analysis of 14 selective attributes that were divided into three factors: 'convenience and taste', 'reliability and health', and 'brand and awareness'. The average importance scores of the first (p < 0.01), second (p < 0.001), and third (p < 0.01) factors in the HG were significantly higher than those in the LG. In addition, the average satisfaction with the first factor (p < 0.01) in the HG was significantly higher than that in the LG. Based on the IPA results, the selective attributes with low satisfaction and high importance were price, origin, food additives, and nutrient content in both the HG and LG. In the second IPA quadrant was safety, but only in the LG. Multiple regression analysis revealed that the importance of the reliability and health factor and the satisfaction with the convenience and taste factor were positively influenced by the subject's taurine-related nutritional knowledge score. These results suggest that reliability and safety of HMR products need to be improved to meet the expectations of Korean consumers aged 40 years and older with a high level of taurine-related nutritional knowledge. Therefore, there is a need to produce HMR products that use safe and reliable food ingredients.

Prevalent Low Thiamine Status Among Adults Living in Seoul Metropolitan Area (South Korea).

The thiamine status of South Korean people has not been recently reported. Therefore, the aim of this study was to determine thiamine intake and status of Korean adults based on a biochemical index. Three consecutive 24-h food recalls and morning first-urine samples were obtained from 143 healthy adults (65 men and 78 women), aged 20-64 years, living in Seoul metropolitan area, Korea. Daily dietary thiamine intake of men and women was 1.42 ± 0.37 mg and 1.18 ± 0.24 mg, respectively. Only 9.1% of the subjects consumed less total thiamine (dietary plus supplemental thiamine) than the estimated average requirement for Koreans. The top 10 major dietary thiamine sources were pork, polished rice, ramyeon (Korean instant noodles), baechukimchi (Chinese cabbage), mandarin oranges, chicken, cow's milk, bread, beef, and potatoes. Those top 10 foods provided 57.85% of the subjects' dietary thiamine intake and the top 30 food sources provided 77.23% of their dietary thiamine intake. Urinary thiamine excretions for men and women were 37.20 ± 26.54 and 39.09 ± 28.80 µg/g creatinine, respectively. Urinary thiamine excretion was positively correlated with total thiamine intake (r = 0.3349, p < 0.0001). Approximately 40% of the subjects had urinary thiamine excretion < 27 µg/g creatinine, indicating thiamine deficiency. In conclusion, thiamine intake among Korean adults in this study was generally adequate, but there was a high prevalence of a low thiamine status. Further study is required to explain the incongruity of adequate intake and low thiamine status thiamine in the South Korean population.