{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T09:01:11Z","timestamp":1776934871306,"version":"3.51.2"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,4,19]],"date-time":"2026-04-19T00:00:00Z","timestamp":1776556800000},"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: Vitamin D deficiency has been implicated in disturbances of glucose and lipid metabolism, particularly in occupational groups with limited sunlight exposure. This study aimed to examine the association between serum 25-hydroxyvitamin D [25(OH)D] concentrations and markers of carbohydrate and lipid metabolism in salt mine workers. Methods: This cross-sectional study involved 62 male salt miners (aged 25\u201363 years), stratified by work depth (surface, \u2264750 m, and &gt;750 m). Anthropometric characteristics, body composition, cardiorespiratory fitness (VO2max), and biochemical parameters were assessed. Blood analyses included fasting glucose, insulin, lipid profile, TSH, and 25(OH)D. Insulin resistance was evaluated via the HOMA-IR index. Results: The cohort exhibited a high prevalence of overweight and obesity (mean BMI &gt; 28 kg\/m2). Significant differences in VO2max were observed between groups (p &lt; 0.05). Elevated fasting glucose (&gt;100 mg\/dL) was observed in 47% of participants, and 22% presented HOMA-IR values &gt; 2.5. In the regression model, vitamin D supplementation was the strongest predictor of 25(OH)D levels, explaining 25.5% of its variance. The addition of HDL cholesterol increased the explained variance to 35.6%, whereas HOMA-IR contributed an additional 3.9% (p = 0.094). Conclusions: In salt miners, insufficient vitamin D status coexists with excess adiposity and impaired glucose homeostasis. Serum 25(OH)D was more strongly associated with supplementation and HDL-C than with HOMA-IR. These findings suggest that monitoring vitamin D status is relevant in the occupational health evaluation of this group.<\/jats:p>","DOI":"10.3390\/nu18081287","type":"journal-article","created":{"date-parts":[[2026,4,20]],"date-time":"2026-04-20T07:15:08Z","timestamp":1776669308000},"page":"1287","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Vitamin D Status and Selected Metabolic Parameters in Salt Mine Workers: A Cross-Sectional Study"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5395-871X","authenticated-orcid":false,"given":"Malwina","family":"Pietrzak","sequence":"first","affiliation":[{"name":"Department of Physiology, Faculty of Health Sciences, University of Physical Education, Kr\u00f3lowej Jadwigi Street 27\/39, 61-871 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3348-8690","authenticated-orcid":false,"given":"Katarzyna","family":"Sobczak","sequence":"additional","affiliation":[{"name":"Department of Swimming and Water Lifesaving, Faculty of Sports Science, Poznan University of Physical Education, Kr\u00f3lowej Jadwigi Street 27\/39, 61-871 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8117-1714","authenticated-orcid":false,"given":"Katarzyna","family":"Domaszewska","sequence":"additional","affiliation":[{"name":"Department of Physiology, Faculty of Health Sciences, University of Physical Education, Kr\u00f3lowej Jadwigi Street 27\/39, 61-871 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1024\/0300-9831\/a000733","article-title":"Sources of Vitamin D for Humans","volume":"92","author":"Benedik","year":"2021","journal-title":"Int. J. Vitam. Nutr. Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"938","DOI":"10.1017\/S1368980011000565","article-title":"The 2011 Report on Dietary Reference Intakes for Calcium and Vitamin D","volume":"14","author":"Ross","year":"2011","journal-title":"Public Health Nutr."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"266","DOI":"10.1056\/NEJMra070553","article-title":"Vitamin D Deficiency","volume":"357","author":"Holick","year":"2007","journal-title":"N. Engl. J. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1186\/s13098-021-00641-8","article-title":"Global Prevalence of Metabolic Syndrome among Patients with Type I Diabetes Mellitus: A Systematic Review and Meta-Analysis","volume":"13","author":"Belete","year":"2021","journal-title":"Diabetol. Metab. Syndr."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Abuhijleh, H., Alkhatib, D., and Ganji, V. (2022). Hypovitaminosis D and Metabolic Syndrome in Postmenopausal Women. Healthcare, 10.","DOI":"10.3390\/healthcare10102026"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"379","DOI":"10.4103\/0366-6999.225059","article-title":"Associations between Body Composition Indices and Metabolic Disorders in Chinese Adults: A Cross-Sectional Observational Study","volume":"131","author":"Zhang","year":"2018","journal-title":"Chin. Med. J."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1007\/BF00280883","article-title":"Homeostasis Model Assessment: Insulin Resistance and \u03b2-Cell Function from Fasting Plasma Glucose and Insulin Concentrations in Man","volume":"28","author":"Matthews","year":"1985","journal-title":"Diabetologia"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1007\/s40519-014-0139-y","article-title":"The Therapy of Insulin Resistance in Other Diseases besides Type 2 Diabetes","volume":"19","author":"Pala","year":"2014","journal-title":"Eat. Weight Disord."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"948","DOI":"10.1006\/bbrc.1993.1717","article-title":"Vitamin D Receptor Gene Expression Is Up-Regulated by 1, 25-Dihydroxyvitamin D3 in 3T3-L1 Preadipocytes","volume":"193","author":"Kamei","year":"1993","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_10","first-page":"258","article-title":"Obesity\u2014The condition predisposing to vitamin D deficiency","volume":"25","year":"2012","journal-title":"Post\u0119py Nauk Med."},{"key":"ref_11","first-page":"00008","article-title":"Shift Work and Sleep: Medical Implications and Management","volume":"1","author":"Jehan","year":"2017","journal-title":"Sleep Med. Disord."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"S17","DOI":"10.1038\/jp.2013.7","article-title":"Health Consequences of Shift Work and Implications for Structural Design","volume":"33","author":"Figueiro","year":"2013","journal-title":"J. Perinatol."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Flo, E., Pallesen, S., Mager\u00f8y, N., Moen, B.E., Gr\u00f8nli, J., Nordhus, I.H., and Bjorvatn, B. (2012). Shift Work Disorder in Nurses\u2014Assessment, Prevalence and Related Health Problems. PLoS ONE, 7.","DOI":"10.1371\/journal.pone.0033981"},{"key":"ref_14","first-page":"1","article-title":"Shift Work and Coronary Heart Disease","volume":"44","author":"Knutsson","year":"1989","journal-title":"Scand. J. Soc. Med. Suppl."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1111\/j.1600-079X.2007.00473.x","article-title":"The Dark Side of Light at Night: Physiological, Epidemiological, and Ecological Consequences","volume":"43","author":"Navara","year":"2007","journal-title":"J. Pineal Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"747","DOI":"10.1136\/oem.58.11.747","article-title":"Is There an Association between Shift Work and Having a Metabolic Syndrome? Results from a Population Based Study of 27 485 People","volume":"58","author":"Karlsson","year":"2001","journal-title":"Occup. Environ. Med."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"502","DOI":"10.5271\/sjweh.1055","article-title":"Workhours in Relation to Work Stress, Recovery and Health","volume":"32","year":"2006","journal-title":"Scand. J. Work Environ. Health"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1016\/S2213-8587(18)30140-2","article-title":"Work Stress and Risk of Death in Men and Women with and without Cardiometabolic Disease: A Multicohort Study","volume":"6","author":"Pentti","year":"2018","journal-title":"Lancet Diabetes Endocrinol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1186\/s40557-016-0135-y","article-title":"Night Shift Work and Inflammatory Markers in Male Workers Aged 20\u201339 in a Display Manufacturing Company","volume":"28","author":"Kim","year":"2016","journal-title":"Ann. Occup. Environ. Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"764","DOI":"10.1111\/jsr.12554","article-title":"Night-Shift Work Is Associated with Poorer Glycaemic Control in Patients with Type 2 Diabetes","volume":"26","author":"Manodpitipong","year":"2017","journal-title":"J. Sleep Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.ssmph.2017.12.003","article-title":"Does Non-Standard Work Mean Non-Standard Health? Exploring Links between Non-Standard Work Schedules, Health Behavior, and Well-Being","volume":"4","author":"Winkler","year":"2018","journal-title":"SSM\u2014Popul. Health"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"\u0160arac, I., Jovanovi\u0107, J., Zec, M., Pavlovi\u0107, Z., Debeljak-Marta\u010di\u0107, J., Zekovi\u0107, M., Mile\u0161evi\u0107, J., Gurinovi\u0107, M., and Glibeti\u0107, M. (2021). Vitamin D Status and Its Correlation With Anthropometric and Biochemical Indicators of Cardiometabolic Risk in Serbian Underground Coal Miners in 2016. Front. Nutr., 8.","DOI":"10.3389\/fnut.2021.689214"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1080\/02701367.1999.10608031","article-title":"Techniques of Body Composition Assessment: A Review of Laboratory and Field Methods","volume":"70","author":"Wagner","year":"1999","journal-title":"Res. Q. Exerc. Sport"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1152\/jappl.1954.7.2.218","article-title":"A Nomogram for Calculation of Aerobic Capacity (Physical Fitness) from Pulse Rate during Sub-Maximal Work","volume":"7","author":"Astrand","year":"1954","journal-title":"J. Appl. Physiol."},{"key":"ref_25","unstructured":"Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences, Routledge. [2nd ed.]."},{"key":"ref_26","first-page":"634195","article-title":"Role of Vitamin D in Insulin Resistance","volume":"2012","author":"Sung","year":"2012","journal-title":"BioMed Res. Int."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.diabres.2018.12.008","article-title":"Does High-Dose Vitamin D Supplementation Impact Insulin Resistance and Risk of Development of Diabetes in Patients with Pre-Diabetes? A Double-Blind Randomized Clinical Trial","volume":"148","author":"Niroomand","year":"2019","journal-title":"Diabetes Res. Clin. Pract."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Rafiq, S., and Jeppesen, P.B. (2021). Vitamin D Deficiency Is Inversely Associated with Homeostatic Model Assessment of Insulin Resistance. Nutrients, 13.","DOI":"10.3390\/nu13124358"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"5713","DOI":"10.1111\/dom.15941","article-title":"Efficacy of Vitamin D Supplementation on Glycaemic Control in Type 2 Diabetes: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials","volume":"26","author":"Chen","year":"2024","journal-title":"Diabetes Obes. Metab."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1007\/s10238-014-0290-9","article-title":"TSH Levels Are Associated with Vitamin D Status and Seasonality in an Adult Population of Euthyroid Adults","volume":"15","author":"Barchetta","year":"2015","journal-title":"Clin. Exp. Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1530\/eje.1.01870","article-title":"Increased Levels of Serum Osteoprotegerin in Hypothyroid Patients and Its Normalization with Restoration of Normal Thyroid Function","volume":"152","author":"Nagasaki","year":"2005","journal-title":"Eur. J. Endocrinol."},{"key":"ref_32","first-page":"364","article-title":"Vitamin B12 and Vitamin D Levels in Patients with Autoimmune Hypothyroidism and Their Correlation with Anti-Thyroid Peroxidase Antibodies","volume":"29","year":"2019","journal-title":"Med. Princ. Pract."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1093\/nutrit\/nuac038","article-title":"Serum 25-Hydroxyvitamin D Levels and Dyslipidemia: A Systematic Review and Dose-Response Meta-Analysis of Epidemiologic Studies","volume":"81","author":"Bahadorpour","year":"2023","journal-title":"Nutr. Rev."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1","DOI":"10.4103\/2230-8210.126517","article-title":"The Hypoglycemic Side of Hypothyroidism","volume":"18","author":"Kalra","year":"2014","journal-title":"Indian J. Endocrinol. Metab."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Leko, M.B., Jure\u0161ko, I., Rozi\u0107, I., Plei\u0107, N., Gunja\u010da, I., and Zemunik, T. (2023). Vitamin D and the Thyroid: A Critical Review of the Current Evidence. Int. J. Mol. Sci., 24.","DOI":"10.3390\/ijms24043586"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2365399","DOI":"10.1155\/2021\/2365399","article-title":"The Association between Anthropometry Indices and Serum Concentrations of Gamma-Glutamyl Transferase, Alkaline Phosphatase, Alanine Aminotransferase, and Aspartate Aminotransferase","volume":"2021","author":"Sobhani","year":"2021","journal-title":"BioMed Res. Int."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1016\/j.metabol.2007.09.013","article-title":"Correlations of Visceral Fat Accumulation and Atherosclerosis in Japanese Patients with Type 2 Diabetes Mellitus","volume":"57","author":"Anan","year":"2008","journal-title":"Metabolism"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"5098","DOI":"10.1210\/jc.2002-020696","article-title":"Metabolic Effects of Visceral Fat Accumulation in Type 2 Diabetes","volume":"87","author":"Gastaldelli","year":"2002","journal-title":"J. Clin. Endocrinol. Metab."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Shantavasinkul, P.C., and Nimitphong, H. (2022). Vitamin D and Visceral Obesity in Humans: What Should Clinicians Know?. Nutrients, 14.","DOI":"10.3390\/nu14153075"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"228","DOI":"10.5455\/njppp.2017.7.0825804092016","article-title":"A Cross-Sectional Study of Association of Body Mass Index and VO2 Max by Nonexercise Test in Medical Students","volume":"7","author":"Kalyanshetti","year":"2017","journal-title":"Natl. J. Physiol. Pharm. Pharmacol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1123\/pes.25.1.43","article-title":"Scaling of VO2max and Its Relationship With Insulin Resistance in Children","volume":"25","author":"Ahn","year":"2013","journal-title":"Pediatr. Exerc. Sci."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1034","DOI":"10.1038\/oby.2011.379","article-title":"Hepatic Steatosis and Low Cardiorespiratory Fitness in Youth With Type 2 Diabetes","volume":"20","author":"Wittmeier","year":"2012","journal-title":"Obesity"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1249\/MSS.0b013e31823cef5e","article-title":"Lifestyle Intervention Improves Fitness Independent of Metformin in Obese Adolescents","volume":"44","author":"Rynders","year":"2012","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_44","first-page":"22857","article-title":"Higher Blood Glucose Level Associated with Body Mass Index and Gut Microbiota in Elderly People","volume":"25","author":"Sepp","year":"2014","journal-title":"Microb. Ecol. Health Dis."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"Khanam, M.A., Qiu, C., Lindeboom, W., Streatfield, P.K., Kabir, Z.N., and Wahlin, \u00c5 (2011). The Metabolic Syndrome: Prevalence, Associated Factors, and Impact on Survival among Older Persons in Rural Bangladesh. PLoS ONE, 6.","DOI":"10.1371\/journal.pone.0020259"},{"key":"ref_46","first-page":"29","article-title":"Zgony sercowe w g\u00f3rnictwie, jako wska\u017anik wydolno\u015bci s\u0142u\u017cby medycyny pracy","volume":"LXI","author":"Skowronek","year":"2011","journal-title":"Arch. Med. S\u0105dowej I Kryminol."},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Sowah, D., Fan, X., Dennett, L., Hagtvedt, R., and Straube, S. (2017). Vitamin D Levels and Deficiency with Different Occupations: A Systematic Review. BMC Public Health, 17.","DOI":"10.1186\/s12889-017-4436-z"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"181","DOI":"10.4103\/ijcm.IJCM_269_19","article-title":"Association of Vitamin D Levels in Coal Miners: A Case\u2013Control Study","volume":"45","author":"Dash","year":"2020","journal-title":"Indian J. Community Med."}],"container-title":["Nutrients"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6643\/18\/8\/1287\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T08:29:22Z","timestamp":1776932962000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6643\/18\/8\/1287"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,19]]},"references-count":48,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["nu18081287"],"URL":"https:\/\/doi.org\/10.3390\/nu18081287","relation":{},"ISSN":["2072-6643"],"issn-type":[{"value":"2072-6643","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,19]]}}}