Vitamin D has been enjoying time in the spotlight in recent years. More like a prohormone than a vitamin, Vitamin D has been shown to do more than just protect bones. Besides its many benefits to the immune system, we now know Vitamin D has a significant impact on sleep quality and duration. Vitamin D regulates tryptophan conversion to serotonin which then converts to melatonin at night in response to the absence of light. Vitamin D also affects the body’s sensitivity to neurotransmitters such as GABA, a calming neurotransmitter that helps the body relax and stay asleep. Your gut microbiome also has a significant impact on your body’s ability to make GABA and melatonin and the gut microbiome is heavily influenced by Vitamin D. So what does this mean? Recent studies have shown that lower levels of Vitamin D decrease sleep duration (by as much as 45 minutes in some studies) and put you at greater risk for sleep apnea. Sleep quality was also poor in Vitamin D deficient subjects.
Who is at greatest risk for Vitamin D deficiency?
Optimal levels of Vitamin D in blood are debatable but tend to range from 50-70ng/ml. It is best to test your level to determine how much supplementation (if any) is needed. Vitamin D is a fat-soluble vitamin which means it is stored by the liver. Overdoing a supplement could result in toxic levels for the body (although in our practice we have found that very few people achieve toxic levels even when supplementing with high doses for many years). Vitamin D is very easy to test in blood and is inexpensive even without insurance. If you haven’t had your level tested in a while, you can schedule an appointment with us to have your level tested and discussed to determine the correct supplementation dosage. There are also blood spot tests available online where you can test your level in a finger stick that can be done from home. Such as this one.
It is best to get Vitamin D from the sun by spending about 10 minutes daily outside without sunscreen (which would not allow adequate Vitamin D conversion). If you do not get enough sunlight, are unable to go outside without sunscreen or live in the North, you will probably need to supplement. Food sources of Vitamin D include cold water fish like tuna and salmon and mushrooms. When supplementing choose the D3 version, preferably with Vitamin K2 to improve absorption. We love the Orthomolecular Vitamin D3/K2 drops because they have no taste and allow you to easily change the dose by taking more or less drops depending on your needs. You can find these and other high quality Vitamin D supplements on our fullscript store. Taking magnesium in supplemental form can also help with Vitamin D absorption in certain people. If sleep is a major issue for you, taking your Vitamin D with dinner (and some healthy fat to help it absorb) may help improve your sleep quality and duration.
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