The scientific understanding of adipose tissue has advanced tremendously during the past decade. Once thought to be an inert fat storage organ, we now know that adipose tissue serves important functions in energy balance and endocrinology, as well as playing a central role in the development of metabolic diseases. Adipose tissue lipid storage and lipolysis are tightly controlled by hormones, such as insulin, in response to the body’s energy needs. Adipose insulin sensitivity can be measured in vivo in humans using isotopic fatty acid tracers and the insulin clamp technique. These data allow investigators to calculate the plasma insulin concentration that results in a 50% suppression of lipolysis. In obesity, insulin’s action on adipose tissue lipolysis is clearly impaired, resulting in excess free fatty acids in circulation, which can lead to metabolic dysfunction. However, the cause of this impairment is unclear. The chronic, low-grade adipose tissue inflammation seen in obesity was thought to be the cause of adipose tissue insulin resistance. In this review, we discuss the structure of adipose tissue, how normal and abnormal adipose tissue metabolism contributes to metabolic diseases, and how inflammation might or might not play a role in adipose tissue insulin resistance.

Ambient air pollution is a serious public health issue worldwide. A growing number of studies has highlighted the negative effects of air pollution on metabolic syndrome (MetS) and its components, including abdominal obesity, disorders of lipid metabolism, elevated blood pressure, and impaired fasting blood glucose. This review provides a brief overview of epidemiological and genetic interaction studies of the links between chronic exposure to ambient air pollution and MetS and its components, as well as plausible mechanisms underlying these relationships. The cumulative evidence suggests that long-term exposure to air pollution, especially particulate matter, increases the risk of MetS and its components. These associations can be partly modified by baseline characteristics, lifestyle, and health conditions. Gene-by-air-pollution interaction studies, limited to candidate genes in the past, have recently been conducted at an expanded genome-wide level. However, more such studies are needed to comprehensively understand the genetics involved in the association between air pollution and MetS. Mechanistic evidence suggests potential biological pathways, including inflammation, oxidative stress, and endothelial dysfunction.

Background: Parental awareness and involvement are crucial in managing obesity in children and adolescents.Although awareness of obesity-related health risks is increasing, public understanding of specific aspects remains limited. This study examines parental perceptions and practices regarding pediatric obesity in Korea. Methods: An online survey was conducted from June 3 to 14, 2024, targeting 102 parents/guardians of children and adolescents who were overweight or obese according to the 2023 Student Health Examination results. The survey assessed experiences with medical consultations, awareness and management practices regarding obesity, awareness of related policies, and barriers and facilitators for obesity management. Results: A significant gap exists between awareness and actual practice in managing pediatric obesity. Although 90.2% of the respondents recognized the importance of dietary and exercise management, the actual implementation rates were low (68.6% and 66.7%, respectively). Notably, 62.1% of respondents were unaware of any existing national policies or programs: 39.7% were aware of relevant policies, and only 35.3% were aware of related programs. Barriers to obesity management included a lack of awareness and motivation among children and adolescents, insufficient information for parents/guardians, and financial and time constraints. Facilitators of effective management include accurate diagnosis, coordination between schools and healthcare providers, and increased community support. Conclusion Combating pediatric obesity will require improved awareness and education, reduced financial burden, and the promotion of national policies. Strengthening coordination among schools, healthcare providers, and community resources will facilitate the successful management of obesity.

Background: This study aimed to analyze the medical expenses covered by the Korean National Health Insurance Service (KNHIS) according to body mass index (BMI) in Korean adults. Methods: We included 1,170,464 adults (623,498 men and 546,966 women) aged ≥19 years from the KNHISNational Sample Cohort database (2016 to 2019) after excluding individuals with cancer. Average annual medical expenses per person and average annual medical expenses (Korean won [KRW], 1 United States dollar=1,292 KRW) by BMI classification were assessed according to age and sex. Medical expenses comprised those for medication and combined outpatient department (OPD) and hospitalization services. Means and 95% confidence intervals were analyzed using a two-part model. Results: Average annual medical expenses increased in higher BMI quintile groups (P for trend <0.001). Average annual medical expenses per person increased significantly as BMI increased in women but not in men. Average annual medical expenses were highest in the highest quintile of BMI among women and in all age groups.While BMI showed a U-shape association with medical expenses for OPD and hospitalization in young individuals, medical expenses for medication in all age groups and those for OPD and hospitalization in middle-aged individuals increased sharply in the highest BMI quintile. Conclusion All types of average annual medical expenses increased in higher BMI groups in Korean adults, particularly in women. Individuals with the highest BMI quintile incurred the greatest medical expenses among women and across all age groups. Strategies for preventing and managing obesity are warranted to reduce the burden of obesity-related medical expenses.

Obesity and low muscle mass are major public health concerns, especially in older adults, due to their strong links to cardiovascular disease, cancer, and mortality. Beyond body mass index, body composition metrics including skeletal muscle, fat mass, and visceral adipose tissue offer deeper insights into nutrition and disease risk.These measures are essential for both cross-sectional assessments and longitudinal tracking, providing a clearer picture of health changes over time. Selecting body composition assessment tools requires balancing cost, practicality, accuracy, and data quality. The right tools enhance research, refine clinical assessments, and inform targeted interventions. Aligning methods with specific research or clinical goals improves disease risk stratification and advances personalized treatments. This review highlights the importance of integrating body composition assessment into research and clinical practice, addressing knowledge gaps across diverse populations and emphasizing its potential in advancing precision medicine. It also highlights recent advancements in body composition assessment techniques that warrant consideration when evaluating techniques for a specific application.Future efforts should focus on refining these tools, expanding their accessibility, and developing comprehensive risk models that incorporate body composition alongside behavioral, environmental, and genetic factors to improve disease prediction and prevention strategies.

Background: Improving β-cell function can lead to remission in some patients with type 2 diabetes mellitus (T2DM). However, research on pharmacotherapy-induced remission in youth-onset T2DM remains scarce. Our study aimed to identify the clinical characteristics of pediatric patients who experience remission. Methods: We retrospectively reviewed 88 pediatric patients with T2DM followed for at least 1 year at Seoul National University Bundang Hospital between 2013 and 2023. Remission was defined as a glycosylated hemoglobin (HbA1c) level less than 6.5% for at least 3 months after ceasing glucose-lowering pharmacotherapy. Results: Among 88 patients (60 males, 68.2%) diagnosed at an average age of 14.4±2.1 years, 19 patients (21.6%) achieved remission after a median duration of 1.4 years. The remission group had a larger proportion of males (89.5% vs. 62.3%, P=0.024) and a lower urinary albumin-to-creatinine ratio (ACR) at diagnosis (P=0.011). They also showed lower HbA1c levels at 1 year and more significant changes in HbA1c and body mass index (all P<0.05). Higher urinary ACR levels correlated with a longer duration to achieve remission (hazard ratio, 0.928; P= 0.013). In three of the 19 remission patients (15.8%), recurrence occurred after a median of 1.5 years. Conclusion Among Korean youth with T2DM, 21.6% achieved remission after a median duration of 1.4 years.Those who experienced remission were predominantly male, had lower ACR at diagnosis, and had significant weight loss within the first year. Further investigation into the factors influencing remission and long-term outcomes is essential.

Background: Grip strength and muscle-strengthening activity (MSA) have been independently associated with type 2 diabetes mellitus (T2DM). However, analyses that consider grip strength in conjunction with MSA, while factoring in age and sex as well, are limited. Therefore, we aimed to investigate the association of relative grip strength (RGS) and MSA, separately and in combination, with T2DM, considering differences in age and sex. Methods: A total of 27,702 participants aged 19 years and older were included from 2014 to 2021 from the Korea National Health and Nutrition Examination Survey. The association between RGS, MSA, and T2DM was assessed using logistic regression analysis. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for the independent and joint associations of RGS and MSA on T2DM prevalence. Results: Highest (Q4) RGS levels were independently associated with lower odds of T2DM (OR, 0.39; 95% CI, 0.32 to 0.46; P for trend <0.001). Similarly, engaging in MSA 2 o 3 days per week was associated with lower odds of T2DM (OR, 0.80; 95% CI, 0.66 to 0.96), although the trend was not statistically significant (P for trend= 0.775).In the joint analysis, participants with normal RGS and engaging in MSA ≥2 days per week had the lowest odds of T2DM (OR, 0.60; 95% CI, 0.51 to 0.70). Conclusion Higher RGS and engaging in MSA 2 to 3 days per week are independently associated with lower likelihood of T2DM. The combined association of normal RGS and MSA 2 days or more per week shows the greatest benefit for T2DM prevention.