Low D Linked to Daytime Sleepiness and More

causes of fatigue

Some things are worth repeating. Other things are worth shouting from the rooftops. The importance of vitamin D is both of those things. That’s why I’ve been repeating my pro-D message for years now.

In fact, long before the mainstream had picked up on just how important this vital vitamin I’ve been telling readers to top up their levels of D. Over three years ago I advised my female readers to get out into the sun more when I warned you about an association between breast cancer and low D levels.

I revealed the surprising link between vitamin D and type II diabetes years before the mainstream caught on, when we told you about a study that found that those with the highest D levels had the lowest incidence of the disease.

And as a reader you learned about a potential link between death from heart disease and low D levels all the way back in 2009.

Those, of course, are just a couple of examples of how important maintaining your vitamin-D levels is to your health. (For dozens more just visit my online archives here.)

So you probably won’t be very surprised to learn that new research is once again spotlighting the importance of D. In fact, the vitamin is being touted by three different teams of researchers for three very different reasons.

61 Percent Lower Risk of MS

A group of Swedish researchers found that high vitamin-D levels during pregnancy may protect women against the autoimmune disease multiple sclerosis (MS).

The Swedish team reviewed blood samples collected since 1975 for around 291,500 people. When they looked at vitamin-D levels an interesting pattern began to emerge. Pregnant women with the highest levels of D had an impressive 61 percent lower risk of developing multiple sclerosis when compared to women with the lowest levels.

Of course, very few of the people tested had high levels of the vitamin to begin with. Not surprising since, as I’ve explained before, vitamin-D levels have been plummeting over the last decade as we spend less and less time out in the sunshine. And when we do venture out we do so under layers of sunblock and “protective” clothing.

Moms to be Check Your D

It turns out that keeping your D levels up during pregnancy can do more than just protect mom from MS they could help give baby a good start in life as well. According to a study published in the Journal of Clinical Endocrinology and Metabolism, low vitamin-D levels are associated with low birth rates.

Researchers at the University of Pittsburgh followed the births of 2,146 babies whose moms had their vitamin-D levels measured at 26 weeks or less. The babies’ birth weight, head circumference, and placental mass were all measured.

The scientists found that moms who were vitamin-D deficient gave birth to babies that were, on average, 46 g lighter than the other babies. In fact, if mom was vitamin-D deficient during her first trimester she was twice as likely to have a lower birth weight baby.

Sleep Like a Baby With D?

Those are two impressive feats we can add to vitamin D’s already sensational resume, but—believe it, or not—I’m not even done with D yet. According to a new study published in the Journal of Clinical Sleep Medicine, getting enough vitamin D could be the key to curing your daytime sleepiness.

Researchers in Louisiana looked at the cases of 81 sleep-study patients who were having trouble keeping their eyes open during the day, and who were complaining of general pain. It turns out that the sleepier the patient was during the day the lower his or her vitamin-D levels tended to be.

Although these findings don’t yet prove a cause and effect relationship…more study is needed to do that…they do strongly suggest that there’s a link between vitamin-D deficiency and daytime sleepiness. And they are, of course, yet one more good reason to make sure that you’re getting the vitamin D you need to stay healthy.

You can get more vitamin D in your diet by increasing the amount of fatty fish and fresh organic meats and eggs you eat. Fish oil is an excellent way to supplement your D levels. And, of course, my number one recommendation for topping up your D is to step out into the sunshine for a good 20 minutes a day without sunscreen.

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Dr. Allan Spreen

Dr. Allan Spreen

Nationally acclaimed as America’s “Nutrition Physician,” Dr. Spreen has been helping people stay healthy and disease-free as a private doctor, published author, and noted researcher.

In addition to his role as a Senior Member of the prestigious Health Sciences Institute Advisory Panel in Baltimore, MD, Dr. Spreen also coaches diving at the international and Olympic levels. NorthStar Nutritionals is proud to have Dr. Spreen as our Chief Research Advisor.

Dr. Spreen also writes the Guide to Good Health.

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  1. Maureen says

    I’ve heard a lot about Vit D, but had not heard about the daytime sleepiness before. I live in the North so there are 5-6 months where I don’t get outside at all. And even in the summer, with working full time, I only get out one or two days a week. I’m wondering if there is a recommended amount to take if you take the supplements? (I take 2,000 iu of D3 a day). And when you say Vit. D, are you referring to D2, or D3? Does it matter?

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