Objectives: This study aimed to evaluate dietary protein intake and its adequacy among Korean adults during recent 10 years. Methods: Based on the 2010 ~ 2019 Korea National Health and Nutrition Examination Survey (KNHANES) data, a total of 51,296 adults aged 19 years old or more who participated in a one-day 24-hr dietary recall were included. Dietary protein intake was estimated as percentages of total energy (% of energy) and grams per body weight (g/kg/ day) and compared with the 2020 Dietary Reference Intakes for Koreans to evaluate the adequacy of protein intake. In addition, proportions of people whose protein intakes were less than the estimated average requirement (EAR) and above the upper limit of the acceptable macronutrient distribution range (AMDR) (> 20% of energy) were calculated according to sociodemographic characteristics. Results: Protein intake was increased from 14.7% of energy in 2010 to 15.6% of energy in 2019 among Korean adults. However, there was no increase in protein intake relative to the recommended nutrient intake (% RNI) during the recent 10 years. Protein intake relative to the RNI was decreased from 130.2% in 2010 to 121.1% in 2019 (P for trend < 0.0001) among total participants, and a significant decreasing trend was observed in all age groups except for over 65 years old. However, protein intake relative to the RNI was lowest in the elderly (98.6%). Proportions of low protein intake (< EAR) and high protein intake (> AMDR) increased in the past 10 years (P for trend < 0.0001 for all), and these were associated with socioeconomic statuses, such as education and household income levels. Conclusions These findings suggest that protein adequacy in Korean adults has not been improved over the past decade compared with recommended levels. Nutritional education and intervention programs should consider different intake levels according to sociodemographic characteristics.

Purpose: Proteins are major components of the body and essential nutrients for proper growth and development. However, studies on protein intake in children and adolescents are insufficient. A few previous studies have reported the relationship with growth indicators, but results vary depending on the source of protein. Therefore, the current study investigates the relationship between protein intake and overweight and obesity among children and adolescents in Korea. Methods: Based on the 2014–2019 Korea National Health and Nutrition Examination Survey, 5,567 children and adolescents aged 6–18 years, who participated in a 24-hour dietary recall with information on height and weight, were included in this study. Protein intake was estimated as percentage of total energy (% of energy) and was classified into animal and plant protein according to the food source. Overweight and obesity were defined using the 2017 pediatric and adolescent growth chart. Results: Total protein intake of the subjects was estimated as 14.5% of total energy (animal protein 8.3% and plant protein 6.3%). The group with the highest total protein intake had a higher odds ratio (OR) of overweight/obesity than those with the least protein intake (OR, 1.36, 95% confidence interval (CI), 1.10-1.67, p for trend = 0.003). When classified by food source, the group with the highest animal protein intake had a significantly higher OR of overweight/obesity than subjects with the lowest intake (OR, 1.30, 95% CI, 1.05-1.61, p for trend = 0.016). However, plant protein was not significantly associated with overweight/obesity. Conclusions These findings suggest that a high intake of animal protein in children and adolescents increases the risk of being overweight and obese. In order to develop normal growth and prevent obesity in the future, it is necessary to determine an appropriate protein intake level through nutrition education programs and prospective studies on balanced protein intake.

PURPOSE: This study evaluated the glycemic response of diets using estimated glycemic load (eGL), which had been developed for mixed meals for Korean adults, and examined its associations with cardiometabolic risk factors among Korean adults. METHODS: A total of 4,655 men and 6,760 women aged 19 years and above were included from the 2013 ~ 2016 Korea National Health and Nutrition Examination Survey. eGL was calculated by each meal (breakfast, lunch, dinner, and snack) and then summed to give daily total eGL. A multiple logistic regression analysis was used to examine the association. RESULTS: Mean daily total eGL was 112.6 in men and 99.3 in women. Daily total eGL was positively associated with carbohydrate and fiber intakes, but negatively associated with protein and fat intakes in both men and women (p < 0.05 for all). Daily total eGL showed an inverse association with HDL-cholesterol level in both men and women (p = 0.0036 for men and p = 0.0008 for women). Men in the highest quintile of daily total eGL showed a 66% increased risk of hypercholesterolemia (OR, 1.66; 95% CI, 1.10 ~ 2.50; p for trend = 0.0447) compared with those in the lowest quintile. CONCLUSION: These findings suggest that eGL based on carbohydrate, protein, fat and fiber intakes can reflect glycemic response and therefore can be used as an index for dietary planning, nutrition education and in the food industry.
Adult ; Asian Continental Ancestry Group ; Diet ; Dyslipidemias ; Education ; Female ; Food Industry ; Glycemic Load ; Humans ; Hypercholesterolemia ; Korea ; Logistic Models ; Lunch ; Male ; Meals ; Nutrition Surveys ; Risk Factors

PURPOSE: Dietary fiber is a component of carbohydrate that is linked closely with the carbohydrate quality, but few studies have investigated the association of high fiber intake with the cardiometabolic risk factors in Koreans. This study examined the association of high fiber and high carbohydrate intake with the cardiometabolic risk factors among Korean adults.METHODS: This study included 15,095 adults aged ≥20 years, who participated in the 2013 ~ 2017 KNHANES. The dietary intake was obtained using a 24-h dietary recall method. The associations of high fiber and high carbohydrate intake with metabolic syndrome and dyslipidemia were examined by sex using multiple logistic regression analysis.RESULTS: The median of dietary fiber was 23.6 g/day in men and 20.0 g/day in women. Dietary fiber intake increased gradually as dietary carbohydrate groups increased except for ≥80% of energy from the carbohydrate group. Women in the highest quintile of fiber intake showed a 33% lower risk of metabolic syndrome compared with those in the third quintile. When stratified into low fiber (LF) and high fiber (HF) groups using Adequate Intake of fiber for Koreans, men in the third quartile of carbohydrate intake showed a 44% and 51% higher risk of metabolic syndrome and atherogenic dyslipidemia than in the first quartile, respectively, but only in the LF group. Women in the second quartile of carbohydrate intake showed an 83% higher risk of hypercholesterolemia than in the first quartile in the LF group. On the other hand, as no significant association was observed between the carbohydrate intake and metabolic diseases among the HF groups in both sexes.CONCLUSION: These findings suggest that a high fiber intake might be associated with a reduced risk of metabolic syndrome and high carbohydrate intake with a low dietary fiber intake might be associated with an increased risk of several metabolic abnormalities among Korean adults. Further prospective studies will be needed to confirm the effects of high fiber and high carbohydrate intake on the cardiometabolic risk factors among Koreans.
Adult ; Dietary Carbohydrates ; Dietary Fiber ; Dyslipidemias ; Female ; Hand ; Humans ; Hypercholesterolemia ; Logistic Models ; Male ; Metabolic Diseases ; Methods ; Prospective Studies ; Risk Factors

BACKGROUND/OBJECTIVES: Regional disparities in dietary factors might be related to regional disparities in cardiometabolic health. Therefore, this study investigated the associations of cardiometabolic risk factors and dietary factors with regional types in Korean adults. SUBJECTS/METHODS: Based on data from the 2007–2017 Korea National Health and Nutrition Examination Survey, the study included 39,781 adults aged ≥ 19 years who completed the dietary survey and a health examination. Healthy and unhealthy dietary factors (fat, sodium, fruit, and vegetable intakes) were evaluated using 1-day 24-h dietary recall method, as well as the use of nutrition labels with a questionnaire. RESULTS: Of the participants, 48.7%, 36.0%, and 15.2% lived in metropolitan, urban, and rural areas, respectively. Adults living in urban and rural had higher odds ratios (ORs) for obesity (OR for urban, 1.07; 95% confidence interval (CI), 1.01–1.14; OR for rural, 1.14; 95% CI, 1.05–1.24) than adults living in metropolitan areas; these associations were significantly observed in middle-aged adults. Compared to metropolitan residents, rural residents had lower ORs for hypertension in middle-aged (OR, 0.86; 95% CI, 0.76–0.96) and metabolic syndrome in older adults (OR, 0.78; 95% CI, 0.67–0.91). Regarding urban residents, a lower OR for diabetes in middle-aged adults (OR, 0.85; 95% CI, 0.74–0.97) and a higher OR for hypertension in older adults (OR, 1.19; 95% CI, 1.02–1.39) were observed. Overall rural residents had higher ORs of excessive carbohydrate, low fruit, and high salted-vegetable intakes than metropolitan residents. Low fruit intake was positively associated with obesity, metabolic syndrome, and hypertension, after adjustment for regional type and other confounders in total participants. CONCLUSIONS These findings indicate that cardiometabolic risk and unhealthy dietary factors differ among regional types and age groups within Korea. Nutritional policy and interventions should consider regional types for prevention and management of cardiometabolic risk factors.

Purpose: The use of food delivery services is increasing continuously in Korea, which may lead to nutritional problems and obesity. Despite this, the research on the association between delivered food consumption and obesity has been insufficient. This study examined the relationship between delivered food consumption and dietary behaviors and obesity among young adults in Jeju. Methods: An online survey was conducted from March 15 to April 5, 2023; 312 participants aged 19–39 years were included in the final analysis. The frequency, types, and time of delivered food consumption were measured using a questionnaire. The dietary behaviors included the following: eating out, breakfast consumption, recognition of nutrition labels, and eating salty foods, vegetables, and fruit. Obesity was defined using the body mass index based on self-reported body weight and height. Results: Approximately 59.3% of the participants ordered delivery foods more than one time/ week. The frequency of delivered food consumption was higher in people who consumed breakfast < 5 times/week than those who consumed ≥ 5 times/week (p = 0.0088). People who usually eat salty foods tended to consume delivered food more frequently than those who did not (p = 0.0377). On the other hand, people who consumed fruits ≥ 1 time/day had a higher frequency of delivered food consumption than those who consumed fruits < 1 time/day (p = 0.0110). After adjusting for the confounding variables, the group who consumed delivered foods more than three times/week had an increased odds ratio (OR) of obesity compared to those who consumed less one time/week (OR, 2.38; 95% confidence intervals, 1.12–5.06). Conclusion Young adults in Jeju who frequently consume delivered foods tended to have poor dietary habits including skipping breakfast and eating salty, and they had an increased odds of obesity. The overall dietary patterns can be improved by providing nutrition education and developing policies to promote or support healthy food choices when ordering delivered foods or eating out.

BACKGROUND/OBJECTIVES: Dietary sugar intake, particularly added sugar and sugar-sweetened beverages, has received worldwide attention recently. Investigation of dietary behaviors may facilitate understanding of dietary sugar intakes of children and adolescents. However, the relationship between dietary sugar intake and dietary behaviors in the Korean population has not been investigated. Thus, this study aimed to estimate dietary sugar intake and food sources according to sex as well as examine the relationship of dietary sugar intake with frequent snacking and dietary patterns among Korean children and adolescents. SUBJECTS/METHODS: We pooled data from five studies involving Korean children and adolescents conducted from 2002 to 2011. A total of 2,599 subjects aged 9-14 years were included in this study. Each subject completed more than 3 days of dietary records. RESULTS: Mean daily total sugar intake was 46.6 g for boys and 54.3 g for girls. Compared with boys, girls showed higher sugar intakes from fruits (7.5 g for boys and 8.8 g for girls; P = 0.0081) and processed foods (27.9 g for boys and 34.9 g for girls; P < 0.0001). On average, 95.4% of boys and 98.8% of girls consumed snacks during the study period, and total sugar intake showed a significantly increasing trend with increasing energy intake from snacks (P < 0.0001 for both sexes). Two dietary patterns were identified by cluster analysis: Traditional and Westernized patterns. Total sugar intake was higher in the Westernized pattern (56.2 g for boys and 57.2 g for girls) than in the Traditional pattern (46.5 g for boys and 46.3 g for girls). CONCLUSIONS: These results suggest that multilateral and practical development of a nutrition education and intervention program that considers dietary behaviors as well as absolute sugar intake is required to prevent excessive sugar intake in Korean children and adolescents.
Adolescent* ; Beverages ; Child* ; Diet Records ; Education ; Energy Intake ; Female ; Fruit ; Humans ; Korea* ; Snacks

PURPOSE: The purpose of this study was to determine trends in dietary vitamin E intakes and contributing food groups among Korean adults. METHODS: This study included 66,695 subjects aged ≥ 19 years who completed a nutrition survey as part of the Korea National Health and Nutrition Examination Survey (1998, 2001, 2005, 2007~2009, 2010~2012, 2013~2015). We estimated individual daily intakes of α-, β-, γ-, δ-tocopherol, and total vitamin E by linking food consumption data with a vitamin E database of commonly consumed foods. RESULTS: Daily vitamin E intake significantly increased from 6.4 mg α-TE/d in 1998 to 7.7 mg α-TE/d in 2013~2015 (p for trend < 0.0001) among men as well as from 5.4 mg α-TE/d in 1998 to 6.5 mg α-TE/d in 2013~2015 among women (p for trend < 0.0001). However, the intake of vitamin E was lower than the adequate intake (AI) of Dietary Reference Intakes for Koreans 2015 (2015 KDRI). In 2013~2015, men consumed 6.5 mg/d of α-tocopherol, 0.5 mg/d of β-tocopherol, 6.0 mg/d of γ-tocopherol, and 3.9 mg/d of δ-tocopherol, whereas women consumed 5.7 mg/d of α-tocopherol, 0.4 mg/d of β-tocopherol, 4.8 mg/d of γ-tocopherol, and 2.8 mg/d of δ-tocopherol. The major food groups contributing to vitamin E intake were vegetables (men: 23.3%, women: 22.7%), grains (men: 14.5%, women: 13.9%), and eggs (men: 13.0%, women: 12.5%). CONCLUSION: This study provides scientific evidence for vitamin E intake in Korean adults. Since the current intake of vitamin E was lower than the reference intakes set by 2015 KDRI, dietary vitamin E intake should be monitored regularly among Korean adults.
Adult* ; Eggs ; Female ; Humans ; Korea* ; Male ; Nutrition Surveys* ; Ovum ; Recommended Dietary Allowances ; Tocopherols ; Vegetables ; Vitamin E* ; Vitamins*

Purpose: Recently, high-protein diets have become highly popular, and the market for protein products has steadily increased in Korea together with the development of various types of such products. However, there is limited information on the consumption of protein supplements (PS) or protein-fortified foods (PF). Thus, this study aimed to evaluate the use of PS/PF among young adults in Jeju. Methods: A total of 350 adults (140 men and 210 women) aged 19–39 years voluntarily participated in this study from June 2022 to May 2023. PS/PF use was measured using a questionnaire. Dietary intake was assessed using a 24-hour dietary recall. Results: Approximately 31.4% of the participants (n = 110) had consumed PS/PF for more than 2 weeks during the past year and 71.8% of them (n = 79) were still consuming these products (PS/PF consumers). The PS/PF consumers tended to be male and physically active (p < 0.05 for all). The most frequent reason for PS/PF use was muscle gain (59.5%), followed by protein supplementation (19.0%) and body fat loss (13.9%), and the most frequent type of PS/PF consumed was powders (70.6%), followed by drinks (17.7%) and bars (8.8%). The PS/PF consumers tended to consume a high-protein low-carbohydrate diet compared to the non-consumers. The prevalence of consuming dietary protein less than the estimated average requirement (EAR) was significantly lower in PS/PF consumers (13.9%) compared to non-consumers (25.4%; p = 0.0316). Conclusion These findings indicate that the necessity of protein supplementation should be determined based on the current dietary protein intake and individual requirements. The study also provides the basic information for establishing guidelines for appropriate protein intake.

Electroconvulsive shock (ECS) induces not only an antidepressant effect but also adverse effects such as amnesia. One potential mechanism underlying both the antidepressant and amnesia effect of ECS may involve the regulation of serotonin (5-hydroxytryptamine) 6 (5-HT6) receptor, but less is known about the effects of acute ECS on the changes in 5-HT6 receptor expression in the hippocampus. In addition, as regulation of 5-HT receptor expression is influenced by the number of ECS treatment and by interval between ECS treatment and sacrifice, it is probable that magnitude and time-dependent changes in 5-HT6 receptor expression could be influenced by repeated ECS exposure. To explore this possibility, we observed and compared the changes of 5-HT6 receptor immunoreactivity (5-HT6 IR) in rat hippocampus at 1, 8, 24, or 72 h after the treatment with either a single ECS (acute ECS) or daily ECS for 10 days (chronic ECS). We found that acute ECS increased 5-HT6 IR in the CA1, CA3, and granule cell layer of hippocampus, reaching peak levels at 8 h and returning to basal levels 72 h later. The magnitude and time-dependent changes in 5-HT6 IR observed after acute ECS were not affected by chronic ECS. These results demonstrate that both acute and chronic ECS transiently increase the 5-HT6 IR in rat hippocampus, and suggest that the magnitude and time-dependent changes in 5-HT6 IR in the hippocampus appear not to be influenced by repeated ECS treatment.
Amnesia ; Animals ; Electroshock* ; Hippocampus* ; Rats* ; Serotonin