I’ve discussed the importance of adequate vitamin D levels before. You can read the full article here. To quickly recap, vitamin D insufficiency (levels less than 30 ng/ml) is incredibly common. One study found it affects 57% of Americans (1). Inadequate vitamin D is associated with osteoporosis, fractures, autoimmune disease, cancer, cardiovascular disease, thyroid issues and difficulty losing weight.
What I haven’t written about before is the connection between vitamin D and sleep! And as you know, I’m a huge advocate of sleep. Sleep disturbance and inadequate sleep is becoming increasingly common. One in six adults has a diagnosed sleep disorder and one in eight has trouble sleeping and reports using sleep aids (2). What if there was a simple solution that could address the root cause?
One study suggests that vitamin D deficiency is the cause of the epidemic of sleep disorders (3). The same study found that of 1,500 patients with neurological complaints and abnormal sleep, most had improvement in sleep through maintaining levels of vitamin D between 60-80 ng/ml. Additionally, in comparing regions of the brain associated with sleep-wake regulation and vitamin D, neurons suggested a direct effect of vitamin D on sleep.
But that’s not all, the evidence is clear:
This study found that higher vitamin D levels are significantly associated with shorter time to fall asleep (4).
Low levels of total serum vitamin D are associated with poorer sleep including short sleep duration and lower sleep efficiency (5).
There is a significant correlation between vitamin D levels and severity of restless legs syndrome which negatively impacts sleep (6)
Higher vitamin D levels are associated with being able to stay asleep (7)
What to do? First, ask your doctor to check your vitamin D levels. If you have problems falling or staying asleep or any of the concerns mentioned above, aim for a vitamin D level between 60 and 80 ng/ml. Most lab reference ranges for vitamin D are 30-100 ng/ml indicating that above 30 ng/ml is sufficient - however, the research for vitamin D and sleep suggests the sufficient range is much higher at 60-80 ng/ml.
With fall nearing and less time out in the sun, you’ll likely need to supplement vitamin D in order to maintain an optimal range and especially if you are deficient. I typically recommend 5,000 IU of vitamin D per day to increase levels and 2,000 IU per day to maintain. Keep in mind, vitamin D is a fat soluble nutrients do you have to take it with a meal or snack that contains fat to absorb it properly.
But the best way to get vitamin D is from the sun so get out there and enjoy the sunshine! It's good for mind, body and sleep.