Background: The mechanism and clinical significance of low circulating 25-hydroxyvitamin D [25(OH)D] in obese people are unknown. Low total 25(OH)D may be due to low vitamin D-binding proteins (DBPs) or faster metabolic clearance. However, obese people have a higher bone mineral density (BMD), which suggests that low 25(OH)D may not be associated with adverse consequences for bone.
Objective: We sought to determine whether 1) vitamin D metabolism and 2) its association with bone health differ by body weight.
Design: We conducted a cross-sectional observational study of 223 normal-weight, overweight, and obese men and women aged 25-75 y in South Yorkshire, United Kingdom, in the fall and spring. A subgroup of 106 subjects was also assessed in the winter. We used novel techniques, including an immunoassay for free 25(OH)D, a stable isotope for the 25(OH)D3 half-life, and high-resolution quantitative tomography, to make a detailed assessment of vitamin D physiology and bone health.
Results: Serum total 25(OH)D was lower in obese and overweight subjects than in normal-weight subjects in the fall and spring (geometric means: 45.0 and 40.8 compared with 58.6 nmol/L, respectively; P < 0.001) but not in the winter. Serum 25(OH)D was inversely correlated with body mass index (BMI) in the fall and spring and in the winter. Free 25(OH)D and 1,25-dihydroxyvitamin D [1,25(OH)2D] were lower in obese subjects. DBP, the DBP genotype, and the 25(OH)D3 half-life did not differ between BMI groups. Bone turnover was lower, and bone density was higher, in obese people.
Conclusions: Total and free 25(OH)D and 1,25(OH)2D are lower at higher BMI, which cannot be explained by lower DBP or the shorter half-life of 25(OH)D3 We speculate that low 25(OH)D in obesity is due to a greater pool of distribution. Lower 25(OH)D may not reflect at-risk skeletal health in obese people, and BMI should be considered when interpreting serum 25(OH)D as a marker of vitamin D status.
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http://dx.doi.org/10.3945/ajcn.115.120139 | DOI Listing |
Curr Obes Rep
January 2025
Department of Endocrinology and Metabolism, Zhuhai People's Hospital (The Affiliated Hospital of Beijing Institute of Technology, Zhuhai Clinical Medical College of Jinan University), Zhuhai, China.
Purpose Of Review: Review the latest data regarding the intersection of adipose tissue (AT) and iron to meet the needs of AT metabolism and the progression of related diseases.
Recent Findings: Iron is involved in fundamental biological metabolic processes and is precisely fine-tuned within the body to maintain cellular, tissue and even systemic iron homeostasis. AT not only serves as an energy storage depot but also represents the largest endocrine organ in the human body, maintaining systemic metabolic homeostasis.
BMJ Open
January 2025
Department of Anesthesiology, Southwest Jiaotong University, the Third People's Hospital of Chengdu, Chengdu, Sichuan, China
Introduction: The global prevalence of obesity and its associated comorbidities is rising, with bariatric surgery emerging as a highly efficacious intervention for obese patients. Postoperative nausea and vomiting (PONV) is a common complication following bariatric surgery, with a standardised protocol for its prevention and management yet to be established. This study aims to determine the incidence and the influencing factors of PONV following various types of bariatric surgeries, thereby facilitating the targeted prevention strategies.
View Article and Find Full Text PDFJ Med Internet Res
December 2024
Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong, China (Hong Kong).
Background: Obesity could compromise people's health and elevate the risk of numerous severe chronic conditions and premature mortality. Young adults are at high risk of adopting unhealthy lifestyles related to overweight and obesity, as they are at a phase marked by several significant life milestones that have been linked to weight gain. They gain weight rapidly and excess adiposity mostly accrues, compared with middle-aged and older adults when weight stabilizes or even decreases.
View Article and Find Full Text PDFJ Pediatr (Rio J)
December 2024
The University of Texas Health Science Center at Houston, School of Public Health in Austin, Department of Epidemiology, Michael & Susan Dell Center for Healthy Living, Texas Physical Activity Research Collaborative (Texas PARC), Austin, TX, USA. Electronic address:
Objective: This study aimed to assess the prevalence of the double burden of malnutrition (DBM) at the individual level in children and adolescents through a comprehensive literature review.
Sources: Electronic databases, including PubMed, Scopus, and Web of Science, were searched for articles published up until September 9, 2022. Studies reporting individual-level DBM in children and adolescents were included, and meta-regression models were used to investigate potential causes of heterogeneity across studies.
Prostaglandins Leukot Essent Fatty Acids
December 2024
Department of Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Austria; Department of Medicine III and Karl Landsteiner Institute for Metabolic Diseases and Nephrology, Clinic Hietzing, Vienna, Austria. Electronic address:
Background And Aims: Obesity is associated with a higher risk of severe diseases such as atherosclerotic cardiovascular disease, type 2 diabetes mellitus (T2DM), and metabolic dysfunction-associated steatotic liver disease (MASLD). Polyunsaturated fatty acids, of the omega-3 family (n-3 PUFA), have been shown to reduce adipose tissue inflammation in obesity, as well as to have lipid-lowering effects and improve insulin sensitivity. However, direct effects on liver transcriptome in humans have not been described.
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