Vitamin D and sleep

I have been working at increasing the amount of deep sleep I get. I have done a lot of experiments and have been unable to move the needle.

I finally figured out that Vitamin D was greatly impacting the amount of deep sleep I was getting.

I posted all of the details here.

I will take questions here or there. I’m guessing a lot of QS’ers are taking Vitamin D so it would be cool to nail this down.

Interesting post, Chris! When did you take Vitamin D? People have noted different effects on sleep depending on time taken.

Yes. I reference some of those in my post. It didn’t matter at this level. After I read Seth Robert’s posts on the topic, I made sure I took Vit D in the morning. I was taking it in the morning for several months before I totally quit.

Worth mentioning that Gwern has quantified how Vitamin D at night hurts sleep, but taken in the morning, it improves sleep.

Dr Gominak, among others, recommends a blood vitamin D3 level of 60-80 ng/ml. Dr. Gominak’s position is that lower or higher levels may cause abnormal sleep. It is therefore important to have blood levels checked regularly when taking Vitamin D supplements.


I’ve recently received my InsideTracker results, and my Vitamin D was 29 ng/ml, which falls into the “insufficient” range. I can attest to abnormal sleep patterns.

Vitamin D receptors, as well as the enzymes that control their activation and degradation, are found in various brain regions that regulate sleep. Vitamin D is also involved in the creation of Melatonin, a hormone that controls human circadian cycles and sleeps patterns. Learn More.

Fascinating! I will change my Vitamin D supplement to the morning. Did you have any benefits that offset the effect on sleep?

basically i noticed something similar. Whenever I don’t take my Vitamin D supplement for a week, my sleep patterns worsen. (+ if i take days off in a sunny place, i sleep much better)