A new randomized controlled trial (RCT) published in the journal Nutritional Neuroscience found that vitamin D supplementation improved sleep quality, increased sleep duration and decreased the time it takes to fall asleep among 20 to 50-year old adults with sleep disorders.
Sleep disorders pose a significant threat to public health, with sleeplessness linked to diabetes, coronary heart disease and motor vehicle crashes. Approximately 35% to 40% of the U.S. adult population are affected by difficulties falling asleep or daytime sleepiness.
Research has shown that vitamin D may play a role in sleep quality through its effects on the circadian rhythm, the internal clock that instructs the body when to sleep, eat and rest. Observational studies have supported this hypothesis by demonstrating a relationship between low vitamin D levels and poor sleep quality. Furthermore, a case report discovered that vitamin D supplementation resolved daytime sleepiness consisting of heavy daytime napping and pervasive fatigue in a 28-year-old woman.