Work

Association of vitamin D and B12 levels with actigraphic sleep in cognitively unimpaired middle-aged and older adults

Year: 2026

Type: article

Abstract: BACKGROUND: Low vitamin D and B12 levels are linked to low self-reported sleep quality and conditions comorbid with sleep disturbances in older adults. We examined the associations between serum vitamin D and B12 levels with actigraphic sleep indices in middle-aged and older adults. METHODS: We studied 460 participants aged 40 and older (70.9 ± 12.0 [SD] years; 52.8% female; 22.2% Black) in the Baltimore Longitudinal Study of Aging. Predictors included total serum vitamin D and B12, sleep outcomes included total sleep time (TST, minutes), sleep efficiency (SE, %), sleep onset latency (minutes), wake after sleep onset (WASO, minutes), and average wake bout length (WBL, minutes). We examined race and sex as effect modifiers of associations between vitamins and sleep. RESULTS: Higher vitamin D concentration was associated with longer TST (B = 23.63 minutes, 95% CI, 9.62-37.64) and shorter WBL (B = -0.29 minutes, 95% CI, -0.50 to -0.09). Vitamin D deficiency was associated with shorter TST (B= -23.03 minutes, 95% CI, -42.05 to -4.01). The associations between vitamin D and sleep were stronger among Black participants. Higher B12 was associated with shorter WASO in women but longer WASO in men. B12 insufficiency/deficiency was associated with longer TST in men but shorter TST in women. CONCLUSIONS: Higher vitamin D levels are associated with longer and less disturbed sleep in middle-aged and older adults. Future studies are needed to understand if maintaining optimal vitamin D levels improve sleep quality and promote better sleep-associated health outcomes.

Source: The Journals of Gerontology Series A

DOI: 10.1093/gerona/glag212