Abstract
We prospectively assessed changes in free 25-hydroxyvitamin D [25(OH)D] and vitamin D binding protein (VDBP) among overweight adults who followed a pescatarian Orthodox intermittent fasting regimen (n = 59) and controls who followed a low-fat 12:12 diet (n = 46). Total and free 25(OH)D, parathyroid hormone, VDBP, anthropometric data, and amino acid intake were evaluated in both groups at three time points: at baseline, 7 weeks after diet implementation, and 5 weeks after participants returned to their usual eating habits (12 weeks from baseline). An increase in amino acid intake between baseline and 12 weeks was independently correlated with higher free 25(OH)D values at 12 weeks for both groups. Our findings suggest that diet can affect free 25(OH)D concentrations, through variations in amino acid intake, independently of exposure to sunlight, providing novel mechanistic insights into the future planning of vitamin D supplementation strategies. However, this hypothesis needs to be tested in larger studies.
Author contributions
SNK conceptualised and designed the study. SNK, TK, and LA collected all data. LA designed the diets. PK, KT, and KM conducted the biochemical analysis of the samples. GD performed the statistical analysis and data interpretation. SNK, TK, PZ and KK analysed and interpreted the dietary data and the biochemical results. SNK and TK performed the literature review and drafted the first version of the manuscript. All authors have read and critically reviewed the manuscript and approved the final version.
Disclosure statement
No potential conflict of interest was reported by the author(s).