Quantifying the food sources of basal vitamin d input

Cutaneous synthesis and traditional food sources do not fully account for unsupplemented vitamin D status. Non-traditional food sources may be an undiscovered input. In a cohort of 780 non-supplement-taking adults with a mean serum 25-hydroxyvitamin D [25(OH)D] of 33 (±14)ng/ml we assessed the relationship between vitamin D status and selected food sources. Serum 25(OH)D concentration was adjusted for season, UVB exposures, and body size. These adjusted values were then regressed against multiple food items and combinations. Whole milk cottage cheese, eggs, red meat, and total protein were positively associated with total 25(OH)D and/or 25(OH)D3 (P<0.05 for each), whereas fish and milk intake were not. The slope of the relationship was such that for every intake of 1serving/day, serum 25(OH)D rose by about 2ng/ml for eggs and 1ng/ml for meat and total protein. For every weekly serving of whole milk cottage cheese, serum 25(OH)D rose by about 1ng/ml. While some food sources were significant predictors of vitamin D status, their ability to explain inter-individual variability was limited. Supplementation will likely remain essential to improving vitamin D status on a population level. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.