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Cited by 3,204Vitamin D Research StudiesParathyroid Disorders and TreatmentsVitamin K Research Studies

The DOI matches its Crossref record; 19 of the 19 references it cites were found in a registry or an index.

Decreased bioavailability of vitamin D in obesity

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Wortsman, Jacobo, Matsuoka, Lois Y, Chen, Tai C, Lu, Zhiren, Holick, Michael F·2000·The American Journal of Clinical Nutrition
DOI 10.1093/ajcn/72.3.690
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Abstract

Background Obesity is associated with vitamin D insufficiency and secondary hyperparathyroidism.Objective This study assessed whether obesity alters the cutaneous production of vitamin D(3) (cholecalciferol) or the intestinal absorption of vitamin D(2) (ergocalciferol).Design Healthy, white, obese [body mass index (BMI; in kg/m(2)) > or = 30] and matched lean control subjects (BMI </= 25) received either whole-body ultraviolet radiation or a pharmacologic dose of vitamin D(2) orally.Results Obese subjects had significantly lower basal 25-hydroxyvitamin D concentrations and higher parathyroid hormone concentrations than did age-matched control subjects. Evaluation of blood vitamin D(3) concentrations 24 h after whole-body irradiation showed that the incremental increase in vitamin D(3) was 57% lower in obese than in nonobese subjects. The content of the vitamin D(3) precursor 7-dehydrocholesterol in the skin of obese and nonobese subjects did not differ significantly between groups nor did its conversion to previtamin D(3) after irradiation in vitro. The obese and nonobese subjects received an oral dose of 50000 IU (1.25 mg) vitamin D(2). BMI was inversely correlated with serum vitamin D(3) concentrations after irradiation (r = -0.55, P: = 0.003) and with peak serum vitamin D(2) concentrations after vitamin D(2) intake (r = -0.56, P: = 0.007).Conclusions Obesity-associated vitamin D insufficiency is likely due to the decreased bioavailability of vitamin D(3) from cutaneous and dietary sources because of its deposition in body fat compartments.

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Metadata

Authors
Wortsman, J., Matsuoka, L. Y., Chen, T. C., Lu, Z., & Holick, M. F.
Affiliations
SIU Medicine (US)
ORCID
Venue
The American Journal of Clinical Nutrition
Publisher
Elsevier BV
Published
2000-09
Volume
72
Issue
3
Pages
690-693
ISSN
0002-9165 (ISSN-L)
DOI
10.1093/ajcn/72.3.690
OpenAlex
W2157304718
Cited by
3,204
References
19
Citations by year
2026: 73 · 2025: 89 · 2024: 97 · 2023: 138 · 2022: 190 · 2021: 173 · 2020: 177 · 2019: 158 · 2018: 183 · 2017: 194 · 2016: 189 · 2015: 213 · 2014: 215 · 2013: 231 · 2012: 193
FWCI
5.20
Type
journal article
Language
en
Open access
Licence
Locations
  • American Journal of Clinical Nutrition (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institute of Arthritis and Musculoskeletal and Skin Diseases (AR369637)
  • National Center for Research Resources (MO1 RR 00533, M01RR000533)
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Vitamin D Research Studies
  • Health Sciences › Medicine › Nephrology › Parathyroid Disorders and Treatments
  • Health Sciences › Nursing › Nutrition and Dietetics › Vitamin K Research Studies
Keywords
obesity, vitamin D bioavailability, vitamin D insufficiency, 25-hydroxyvitamin D, parathyroid hormone, secondary hyperparathyroidism, UV irradiation, 7-dehydrocholesterol, previtamin D3, vitamin D2, body fat storage
MeSH terms
Adult, Biological Availability, Cholecalciferol, Ergocalciferols, Humans, Intestinal Absorption, Obesity, Reference Values, Skin, Ultraviolet Rays, Vitamin D, Body Mass Index

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