Diet is a major lifestyle-related risk factor of various chronic diseases. Dietary intake can be assessed by subjective report and objective observation. Subjective assessment is possible using open-ended surveys such as dietary recalls or records, or using closed-ended surveys including food frequency questionnaires. Each method has inherent strengths and limitations. Continued efforts to improve the accuracy of dietary intake assessment and enhance its feasibility in epidemiological studies have been made. This article reviews common dietary assessment methods and their feasibility in epidemiological studies.

https://www.e-epih.org/upload/pdf/epih-36-e2014009.pdf

Dietary assessment methods in epidemiologic studies.

Liver diseases in the Asia-Pacific region: a Lancet Gastroenterology & Hepatology Commission.

Background: The objective of this study was to investigate the prevalence, management, and comorbidities of diabetes among Korean adults aged 30 years and older.
Methods: This study used 2013 to 2016 data from the Korea National Health and Nutrition Examination Survey, a nationally-representative survey of the Korean population. Diabetes was defined as fasting glucose ≥126 mg/dL, current use of antidiabetic medication, a previous history of diabetes, or glycosylated hemoglobin (HbA1c) ≥6.5%.
Results: In 2016, 14.4% (approximately 5.02 million) of Korean adults had diabetes. The prevalence of impaired fasting glucose was 25.3% (8.71 million). From 2013 to 2016, the awareness, control, and treatment rates for diabetes were 62.6%, 56.7%, and 25.1%, respectively. People with diabetes had the following comorbidities: obesity (50.4%), abdominal obesity (47.8%), hypertension (55.3%), and hypercholesterolemia (34.9%). The 25.1%, 68.4%, and 44.2% of people with diabetes achieved HbA1c <6.5%, blood pressure <140/85 mm Hg, and low density lipoprotein cholesterol <100 mg/dL. Only 8.4% of people with diabetes had good control of all three targets.
Conclusion: This study confirms that diabetes is as an important public health problem. Efforts should be made to increase awareness, detection, and comprehensive management of diabetes to reduce diabetes-related morbidity and mortality.

/pdf/diabetes-fact-sheets-in-korea-2020-an-appraisal-of-current-51cybxm3q4.pdf

Diabetes Fact Sheets in Korea, 2020: An Appraisal of Current Status.

Real-world evidence (RWE) and randomized control trial (RCT) data are considered mutually complementary. However, compared with RCT, the outcomes of RWE continue to be assigned lower credibility. It must be emphasized that RWE research is a real-world practice that does not need to be executed as RCT research for it to be reliable. The advantages and disadvantages of RWE must be discerned clearly, and then the proper protocol can be planned from the beginning of the research to secure as many samples as possible. Attention must be paid to privacy protection. Moreover, bias can be reduced meaningfully by reducing the number of dropouts through detailed and meticulous data quality management. RCT research, characterized as having the highest reliability, and RWE research, which reflects the actual clinical aspects, can have a mutually supplementary relationship. Indeed, once this is proven, the two could comprise the most powerful evidence-based research method in medicine.

/pdf/real-world-evidence-versus-randomized-controlled-trial-1cn7n55gxh.pdf

Real-world Evidence versus Randomized Controlled Trial: Clinical Research Based on Electronic Medical Records.

Background
Government and health organisations worldwide have recently reviewed the evidence on the role of dietary sugars in relation to health outcomes. Hence, it is timely to review current intakes of dietary sugars with respect to this guidance and as a benchmark for future surveillance.

Methods
This review collates data from nationally representative dietary surveys across the world and reports estimates of intakes of total and added sugars, and sucrose in different population subgroups. Total sugars includes all mono- and disaccharides; namely, glucose, fructose, lactose, sucrose and maltose. Added and free sugars differ in the quantity of natural sugars included in their definitions. Free sugars include sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates, whereas added sugars typically only refer to those added during processing.

Results
Most countries reported intakes of total sugars, with fewer reporting intakes of added sugars and sucrose. No country reported intakes of free sugars. The available data suggest that total sugars as a percentage of energy were highest in the infant (<4 years), with mean values ranging from 20.0% to 38.4%, and decreased over the lifespan to 13.5–24.6% in adults. Intakes of added sugars were higher in school-aged children and adolescents (up to 19% of total energy) compared to younger children or adults.

Conclusions
Further research into the dietary patterns contributing to added sugars intake in children and adolescents is warranted. It would also be beneficial to policy guidance if future dietary surveys employed a uniform way of expressing sugars that is feasible to measure and has public health significance.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/jhn.12338

A review of sugar consumption from nationally representative dietary surveys across the world.

The Korea National Health and Nutrition Examination Survey (KNHANES) is a national surveillance system that has been assessing the health and nutritional status of Koreans since 1998. Based on the National Health Promotion Act, the surveys have been conducted by the Korea Centers for Disease Control and Prevention (KCDC). This nationally representative cross-sectional survey includes approximately 10 000 individuals each year as a survey sample and collects information on socioeconomic status, health-related behaviours, quality of life, healthcare utilization, anthropometric measures, biochemical and clinical profiles for non-communicable diseases and dietary intakes with three component surveys: health interview, health examination and nutrition survey. The health interview and health examination are conducted by trained staff members, including physicians, medical technicians and health interviewers, at a mobile examination centre, and dieticians' visits to the homes of the study participants are followed up. KNHANES provides statistics for health-related policies in Korea, which also serve as the research infrastructure for studies on risk factors and diseases by supporting over 500 publications. KCDC has also supported researchers in Korea by providing annual workshops for data users. KCDC has published the Korea Health Statistics each year, and microdata are publicly available through the KNHANES website (http://knhanes.cdc.go.kr).

/pdf/data-resource-profile-the-korea-national-health-and-3g1oxj0xm4.pdf

Data Resource Profile: The Korea National Health and Nutrition Examination Survey (KNHANES)

Background: Despite social gradients in adult smoking, the effects of socioeconomic position (SEP) on adolescent smoking is not well understood. This study examined effects of subjective SEP as well as the objective SEP on smoking among Korean adolescents. Materials and Methods: Data were obtained from the 2012 Korea Youth Risk Behavior Web-based Survey, a nationally representative sample of middle and high school students (38,221 boys; 35,965 girls). SEP was assessed by the Family Affluence Scale (FAS) and the self-rated household economic status. Relationships between SEP and smoking were analyzed by multivariate logistic regression. Results: The low perceived SEP for either the high or low FAS grade was related to an elevated likelihood of smoking in both genders. A significantly higher risk of smoking was found in boys of low perceived SEP in middle school (odds ratio [OR] 1.50; 95% confidence interval [CI] 1.28-1.77 for high FAS, OR 1.55; 95% CI 1.21-1.98 for low FAS), and of low perceived SEP and high FAS in high school (OR 1.13; 95% CI 1.02-1.26). Among girls, an elevated risk of smoking was observed in middle school group with low perceived SEP and low FAS (OR 2.01; 95% CI 1.44-2.79) and in the high school group of low perceived SEP, regardless of FAS level (OR 1.34; 95% CI 1.14-1.57 for high FAS, OR 1.31; 95% CI 1.04-1.65 for low FAS). Conclusions: The relationship of subjectively perceived SEP with smoking is as important as objective SEP and more significant in Korean high school adolescents.

http://koreascience.or.kr:80/article/JAKO201435648479345.pdf

Objective and subjective socioeconomic position and current smoking among Korean adolescents.

To define the factors that influence the development of metabolic syndrome (MetS) characteristics in adolescents, this study assessed the clustering pattern for MetS using confirmatory factor analysis (CFA). Components of metabolic syndrome, including abdominal obesity, insulin resistance, high blood pressure, and dyslipidemia, were analyzed in 1,514 Korean adolescents aged 10 to 18 years. The validities of one-factor models underlying a unifying etiology and a four-factor model based on more than one physiologic process for MetS across sex and age groups were assessed using the CFA method. The one-factor model, which incorporated waist circumference (WC), homeostasis model assessment-insulin resistance (HOMA-IR), systolic blood pressure (SBP), and high-density lipoprotein (HDL) values, had the best goodness-of-fit indices among the models (comparative fit index 0.99, root mean square error of approximation 0.04), with stability over sex and age groups. MetS was mainly defined by WC, SBP, HOMA-IR, and HDL values, with factor loadings of 0.78, 0.47, 0.44, and −0.37, respectively. WC contributed the most to MetS, with the highest factor loading value across sex and age groups. In conclusion, a single underlying factor representing the common pathway linking abdominal obesity, SBP, HOMA-IR, and HDL may explain MetS in Korean adolescents with stability across sex and age groups.

/pdf/characteristics-of-metabolic-syndrome-based-on-clustering-3m3zjucnnv.pdf

Characteristics of metabolic syndrome based on clustering pattern among Korean adolescents: findings from the Korean National Health and Nutrition Examination Survey, 2007-2008.


 Background: The relationship between macronutrients and frailty is unclear. Previous studies have confirmed the relationships between energy and protein intake and physical frailty, while few studies have examined the role of carbohydrate or fat intake in the prevalence of frailty. The aim of this study is to investigate the relationship of energy and macronutrients with physical frailty in the Korean elderly population who had a high proportion of energy intake from carbohydrates.Methods: This study included 954 adults aged 70 to 84 years who have completed the assessment of frailty and 24-h recall upon enrolment in the Korean Frailty and Aging Cohort Study and have no extreme intake under 400 kcal (n = 2). The relationship between energy or macronutrients and frailty was evaluated using multivariate logistic regression models and multivariate nutrient density models.Results: In the subjects with low energy intake (odds ratio [OR] = 2.94, 95% confidence interval [CI] = 1.34–6.45) and total subjects (OR = 2.01, 95% CI = 1.03–3.93), consuming carbohydrates above the acceptable macronutrient distribution range (65% of energy) was related to a higher risk of frailty. Substituting the energy from fat with carbohydrates was related to a higher risk of frailty (1%, OR = 1.05, 95% CI = 1.00–1.09; 5%, OR = 1.26, 95% CI = 1.02–1.56; 10%, OR = 1.59, 95% CI = 1.03–2.43).Conclusions: This study showed that the proportion of energy intake from carbohydrates and fats may be an important nutritional intervention factor for reducing the risk of frailty.

Kirang Kim

Papers

Data Resource Profile: The Korea National Health and Nutrition Examination Survey (KNHANES)

Objective and subjective socioeconomic position and current smoking among Korean adolescents.

Characteristics of metabolic syndrome based on clustering pattern among Korean adolescents: findings from the Korean National Health and Nutrition Examination Survey, 2007-2008.

The Impact of High Carbohydrate Intake on Physical Frailty in Older Korean Adults: a Cohort-based Cross-sectional Study

The development of resources for the application of 2020 Dietary Reference Intakes for Koreans