{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T19:59:26Z","timestamp":1789070366448,"version":"build-2803163510"},"reference-count":35,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2025,8,12]],"date-time":"2025-08-12T00:00:00Z","timestamp":1754956800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Background\/Objectives: Vitamin D plays an important role in a wide range of health outcomes, including immune regulation, bone metabolism, cardiovascular health, and cancer prevention. However, recent data on the prevalence and risk factors for elevated serum 25-hydroxyvitamin D [25(OH)D] concentrations\u2014indicative of potential vitamin D toxicity\u2014remain limited in Korea. Methods: We conducted a retrospective analysis of laboratory data from individuals who underwent serum 25(OH)D testing between 2020 and 2022. Potential vitamin D toxicity was defined as serum 25(OH)D levels exceeding 50, 100, or 150 ng\/mL. The prevalence of potential toxicity was examined by age, sex, test month, and year. Results: A total of 1,198,947 individuals (mean age, 45.7 \u00b1 19.4 years; 31.6% male) were included in the study. The prevalence of serum 25(OH)D &gt; 50 ng\/mL increased from 4.41% in 2020 to 6.21% in 2022, and that of &gt;100 ng\/mL rose from 0.09 to 0.12% over the same period. The proportions exceeding 50 and 100 ng\/mL also rose significantly (p &lt; 0.05), while &gt;150 ng\/mL remained rare (0.01%) and stable. Elevated 25(OH)D concentrations were more frequently observed among females, children aged 0\u20139 years, and adults aged \u226550 years (adjusted odds ratios for multivariable logistic regression &gt; 1.0, p &lt; 0.05). Conclusions: Although the prevalence of potential vitamin D toxicity remains low, its continuous upward trend highlights the need for increased public awareness, clinical monitoring, and guideline-based supplementation strategies to prevent inadvertent vitamin D intoxication, particularly in the aging population.<\/jats:p>","DOI":"10.3390\/nu17162614","type":"journal-article","created":{"date-parts":[[2025,8,12]],"date-time":"2025-08-12T15:51:02Z","timestamp":1755013862000},"page":"2614","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Increasing Prevalence of Potential Vitamin D Toxicity and Its Risk Factors in Korea: A Large Population-Based Study"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8266-2248","authenticated-orcid":false,"given":"Rihwa","family":"Choi","sequence":"first","affiliation":[{"name":"Laboratory Medicine Center, Division of Laboratory Medicine, GC Labs, Yongin-si 16924, Republic of Korea"},{"name":"Department of Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3710-0828","authenticated-orcid":false,"given":"Gayoung","family":"Chun","sequence":"additional","affiliation":[{"name":"Biostatistics Team, Infectious Disease Research Center, Division of Laboratory Medicine, GC Labs, Yongin-si 16924, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8082-3100","authenticated-orcid":false,"given":"Sung-Eun","family":"Cho","sequence":"additional","affiliation":[{"name":"Endocrine Substance Analysis Center (ESAC), Division of Laboratory Medicine, GC Labs, Yongin-si 16924, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sunhyun","family":"Ahn","sequence":"additional","affiliation":[{"name":"Laboratory Medicine Center, Division of Laboratory Medicine, GC Labs, Yongin-si 16924, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4672-5811","authenticated-orcid":false,"given":"Sang Gon","family":"Lee","sequence":"additional","affiliation":[{"name":"Laboratory Medicine Center, Division of Laboratory Medicine, GC Labs, Yongin-si 16924, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eun Hee","family":"Lee","sequence":"additional","affiliation":[{"name":"Laboratory Medicine Center, Division of Laboratory Medicine, GC Labs, Yongin-si 16924, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1907","DOI":"10.1210\/clinem\/dgae290","article-title":"Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline","volume":"109","author":"Demay","year":"2024","journal-title":"J. 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