Objective To explore the association between serum vitamin D metabolites and sleep duration in adult women.

Methods Women aged 20 to 65 in the National Health and Nutrition Examination Survey (NHANES) database were selected as research objects. Serum vitamin D metabolites including 25-hydroxyvitamin D25(OH)D, 25-hydroxyvitamin D₂25(OH)D₂ and 25-hydroxyvitamin D₃25(OH)D₃ were measured using ultra performance liquid chromatography-tandem mass spectrometry. The study objects were divided into sleep deficiency group and non-sleep deficiency group according to varied sleep duration. Logistic regression model and restrictive cubic spline model were used to analyze the relationship between serum vitamin D concentration and sleep condition after adjusting age, race, education level, marital status, economic status, body mass index(BMI), chronic disease status and depression score.

Results Among 9 353 females, 3 189 (34.1%) had insufficient sleep, including 1 627 (51.0%) aged 20 to 44 years and 1 562 (49.0%) aged 45 to 65 years. With an increase of 10 nmol/L of serum 25(OH)D₃ and 25(OH)D, the incidence of sleep insufficiency decreased by 5.5% and 5.7%, respectivelyOR=1.005 5, 95%CI, 1.003 6 to 1.007 3; OR=1.005 7, 95%CI, 1.003 9 to 1.007 6. The restrictive cubic spline model showed that when serum 25(OH)D₃ is ≤ 70 nmol/L, a strong positive correlation was observed between sleep duration and serum 25(OH)D₃ concentration. However, this positive correlation becomes weaker when serum 25(OH)D₃ was >70 nmol/L.

Conclusion There is an association between the sleep status and the time of serum concentration of vitamin D metabolites in adult women. The sleep duration varies at different vitamin D concentration levels. When the concentration of serum vitamin D metabolites is low, improvement of level of vitamin D metabolites is more conducive to prolongation of sleep time.