Vitamin D insufficiency is associated with obesity and its related metabolic diseases. Adipose tissues store and metabolize vitamin D and expression levels of vitamin D metabolizing enzymes are known to be altered in obesity. Sequestration of vitamin D in large amount of adipose tissues and low vitamin D metabolism may contribute to the vitamin D inadequacy in obesity. Vitamin D receptor is expressed in adipose tissues and vitamin D regulates multiple aspects of adipose biology including adipogenesis as well as metabolic and endocrine function of adipose tissues that can contribute to the high risk of metabolic diseases in vitamin D insufficiency. We will review current understanding of vitamin D regulation of adipose biology focusing on vitamin D modulation of adiposity and adipose tissue functions as well as the molecular mechanisms through which vitamin D regulates adipose biology. The effects of supplementation or maintenance of vitamin D on obesity and metabolic diseases are also discussed.

Objectives: The Thai Osteoporosis Foundation (TOPF) is an academic organization that consists of a multidisciplinary group of healthcare professionals managing osteoporosis. The first clinical practice guideline for diagnosing and managing osteoporosis in Thailand was published by the TOPF in 2010, then updated in 2016 and 2021. This paper presents important updates of the guideline for the diagnosis and management of osteoporosis in Thailand. Methods: A panel of experts in the field of osteoporosis was recruited by the TOPF to review and update the TOPF position statement from 2016. Evidence was searched using the MEDLINE database through PubMed. Primary writers submitted their first drafts, which were reviewed, discussed, and integrated into the final document. Recommendations are based on reviews of the clinical evidence and experts' opinions. The recommendations are classified using the Grading of Recommendations, Assessment, Development, and Evaluation classification system. Results: The updated guideline comprises 90 recommendations divided into 12 main topics. This paper summarizes the recommendations focused on 4 main topics: the diagnosis and evaluation of osteoporosis, fracture risk assessment and indications for bone mineral density measurement, fracture risk categorization, management according to fracture risk, and pharmacological management of osteoporosis. Conclusions This updated clinical practice guideline is a practical tool to assist healthcare professionals in diagnosing, evaluating, and managing osteoporosis in Thailand.