{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T20:17:02Z","timestamp":1779135422322,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,26]],"date-time":"2025-03-26T00:00:00Z","timestamp":1742947200000},"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: Athonian fasting, a rigorous form of intermittent fasting practiced by Christian Orthodox nuns and a subset of the Mediterranean diet, has known health benefits, but its impact on the interplay of adipokines, inflammatory cytokines, and vitamin D status remains under-investigated. This study aimed to elucidate these relationships within this controlled dietary context. Methods: This cross-sectional study examined the interplay of leptin, interleukin-6 (IL-6), and vitamin D in 41 overweight, vitamin D-sufficient Christian Orthodox nuns practicing Athonian fasting. Anthropometric, biochemical, and inflammatory markers were assessed in the nuns (mean age 53.4 \u00b1 17.1 years, median monastery stay 17 years, median BMI 26.8 kg\/m2). Results: Analysis revealed significant positive correlations between age and monastery stay (r = 0.615, p &lt; 0.001), age and visceral fat (\u03c1 = 0.791, p &lt; 0.001), age and IL-6 (\u03c1 = 0.647, p &lt; 0.001), and BMI and IL-6 (\u03c1 = 0.622, p &lt; 0.001). Strong associations existed between adiposity (BMI, body fat, visceral fat), leptin, and IL-6. Specifically, body fat showed substantial positive correlations with visceral fat (\u03c1 = 0.858, p &lt; 0.001), leptin (\u03c1 = 0.538, p &lt; 0.001), and IL-6 (\u03c1 = 0.675, p &lt; 0.001). Visceral fat demonstrated strong positive correlations with leptin (\u03c1 = 0.613, p &lt; 0.001) and IL-6 (\u03c1 = 0.741, p &lt; 0.001). A significant positive correlation was also observed between leptin and IL-6 (\u03c1 = 0.507, p = 0.003). Conversely, a significant negative correlation was found between 25(OH)D and PTH (\u03c1 = \u22120.380, p = 0.016). Multivariate regression analysis did not reveal independent effects of leptin or IL-6 after adjusting for other factors. Conclusions: This study reveals a complex interplay of adiposity, inflammation, and vitamin D status in this unique population of Orthodox monastery fasters. The strong correlations suggest potential targets for interventions aimed at improving metabolic health. Future research should investigate the effects of vitamin D within the context of Athonian fasting.<\/jats:p>","DOI":"10.3390\/nu17071144","type":"journal-article","created":{"date-parts":[[2025,3,26]],"date-time":"2025-03-26T06:58:43Z","timestamp":1742972323000},"page":"1144","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Interrelations of Leptin and Interleukin-6 in Vitamin D Deficient and Overweight Orthodox Nuns from Northern Greece: A Pilot Study"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4225-2746","authenticated-orcid":false,"given":"Spyridon N.","family":"Karras","sequence":"first","affiliation":[{"name":"Laboratory of Biological Chemistry, Medical School, Aristotle University, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5576-2446","authenticated-orcid":false,"given":"Konstantinos","family":"Michalakis","sequence":"additional","affiliation":[{"name":"Endocrine Practice, Department of Obesity and Metabolism, 11521 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0894-2644","authenticated-orcid":false,"given":"Niki","family":"Katsiki","sequence":"additional","affiliation":[{"name":"Department of Nutritional Sciences and Dietetics, International Hellenic University, 57400 Thessaloniki, Greece"},{"name":"School of Medicine, European University Cyprus Nicosia, Nicosia 2404, Cyprus"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Kypraiou","sequence":"additional","affiliation":[{"name":"Assisting Nature Centre of Reproduction and Genetics, 57001 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6901-744X","authenticated-orcid":false,"given":"Antonios","family":"Vlastos","sequence":"additional","affiliation":[{"name":"Medical School, Aristotle University, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5804-4669","authenticated-orcid":false,"given":"Marios","family":"Anemoulis","sequence":"additional","affiliation":[{"name":"Medical School, Aristotle University, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6560-3537","authenticated-orcid":false,"given":"Georgios","family":"Koukoulis","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, University of Thessaly School of Medicine, 41500 Larissa, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zadalla","family":"Mouslech","sequence":"additional","affiliation":[{"name":"1st Medical Propedeutic, Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Filotas","family":"Talidis","sequence":"additional","affiliation":[{"name":"Endocrine Practice, 52100 Kastoria, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8339-9800","authenticated-orcid":false,"given":"Georgios","family":"Tzimagiorgis","sequence":"additional","affiliation":[{"name":"Laboratory of Biological Chemistry, Medical School, Aristotle University, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Costas","family":"Haitoglou","sequence":"additional","affiliation":[{"name":"Laboratory of Biological Chemistry, Medical School, Aristotle University, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5646-8572","authenticated-orcid":false,"given":"\u039cichos","family":"Georgios","sequence":"additional","affiliation":[{"name":"Third Department of Obstetrics and Gynecology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Evangelos G.","family":"Papanikolaou","sequence":"additional","affiliation":[{"name":"School of Medicine, European University Cyprus Nicosia, Nicosia 2404, Cyprus"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Skoutas","family":"Dimitrios","sequence":"additional","affiliation":[{"name":"Thermi Clinic, Internal Medicine and Diabetes Department 14th km National Road Thessalonikis-Moudanion, 57001 Thessaloniki, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neoklis","family":"Georgopoulos","sequence":"additional","affiliation":[{"name":"Division of Endocrinology, Department of Internal Medicine, School of Health Sciences, University of Patras, 26504 Patras, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"232","DOI":"10.3945\/ajcn.110.008458","article-title":"Does global obesity represent a global public health challenge?","volume":"93","author":"Popkin","year":"2011","journal-title":"Am. 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