Vitamins and sleep quality
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Vitamin D and Sleep Quality
Multiple studies show a strong link between vitamin D and sleep quality. Supplementing with vitamin D significantly improves subjective sleep quality, reduces sleep latency, and increases sleep duration in people with sleep disorders or low vitamin D levels 1234. Higher vitamin D levels are also associated with better physical and mental health, and lower scores on sleep disturbance scales, indicating better sleep . Large-scale analyses confirm that vitamin D deficiency increases the risk of sleep disorders, poor sleep quality, short sleep duration, and daytime sleepiness 67. This association is seen in both adults and children, and vitamin D supplementation may help optimize sleep quality, especially in those with sleep disorders like obstructive sleep apnea .
Other Vitamins and Sleep Quality
Vitamin B12 and Sleep
Research on vitamin B12 and sleep quality is less conclusive. One study among young women found that higher serum vitamin B12 levels were linked to better sleep quality scores and less use of sleep medication, but there was no direct association with overall sleep quality . More research is needed to clarify the relationship between vitamin B12 and sleep.
Vitamin B2 (Riboflavin) and Sleep
Vitamin B2 intake may also play a role in sleep quality and alertness. In young men, higher usual vitamin B2 intake was associated with better sleep quality, while in women, higher recent vitamin B2 intake was linked to greater daytime alertness. However, the overall association between vitamin B2 and sleep quality was not significant for the whole group, suggesting possible gender differences that require further study .
Combined Effects and Deficiencies
Deficiencies in both iron and vitamin D are associated with poorer sleep quality, especially in women of reproductive age. Those with both deficiencies have significantly higher odds of poor sleep compared to those with neither deficiency, suggesting a possible synergistic effect .
Conclusion
Vitamin D supplementation consistently shows benefits for improving sleep quality, reducing sleep disturbances, and increasing sleep duration, especially in those with low vitamin D levels or sleep disorders. There is some evidence that vitamin B12 and B2 may also influence sleep quality and alertness, but more research is needed. Addressing vitamin D deficiency, and possibly other vitamin deficiencies, may be an important step in improving sleep health.
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