Early Morning Sun

What’s Up with Vitamin D and the Coronavirus?

The pandemic has been tough on many businesses, but it’s been a boon to others. Dietary supplement sales, for example, are feeding quite nicely on our fears. At the top of the list is vitamin D, getting a boost from speculation that deficiencies could make a person more vulnerable to the coronavirus.

However, the bottom line is that this adds up to nothing but speculation.

Why Speculate?

All the speculation about vitamin D and the coronavirus comes from inconclusive research and observational studies. For example, one study looked at data on vitamin D levels and coronavirus infections in UK Biobank data. Researchers found a higher risk of COVID-19 infections in people with vitamin D deficiencies.  But that correlation disappeared when the researchers factored in potentially confounding variables.

There is research to say that vitamin D deficiency might leave a person vulnerable to a respiratory infection like COVID-19. But folks like Susan Lanham-New, who have studied this question, say that there’s simply not enough evidence to say that vitamin D is playing an important role. So more definitive research is moving ahead.

An Essential Nutrient That’s Easy to Get

In the meantime, we all need vitamin D and there’s no doubt that some of us don’t get enough. For those of us who don’t, it’s easy enough to get what you need. Your skin makes it if you can get out and get enough sunlight to do the trick. Anywhere from 10 to 30 minutes of midday sun several days days a week should do the trick. People with darker skin need more. With fairer skin, you need less. And don’t forget the sunscreen. You can also get vitamin D in your diet, from fatty fish, egg yolks, or fortified milk. And when all else fails, vitamin D supplements are inexpensive and readily available.

However, with vitamin D, you can indeed get too much of a good thing. From food or the sun, it’s not likely, but it can happen with supplements and it has real downsides for your health. So taking vitamin D supplements when they’re not medically indicated is definitely not a good idea.

If you have any doubt that you might have a deficiency, talk to your doctor. A test for vitamin D blood levels is relatively straightforward. And for serious questions about getting enough from your diet, a registered dietitian is your best bet.

Click here for more on the link between coronavirus and vitamin D and here for a wise dietitian’s perspective on supplements and the coronavirus.

Early Morning Sun, photograph © Stanley Zimny / flickr

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June 28, 2020