Your best defense in the age of coronavirus

We recently talked about how Britain’s National Health Service (NHS) issued a recommendation to supplement with vitamin D to help stay healthy during the coronavirus pandemic. Well, it looks like everyone’s gotten the memo now, thanks to a brand new study currently making its rounds.

This new data compared outcomes from a number of different countries, linking vitamin D levels with both the symptom severity and mortality rate of patients with COVID-19. And this led the authors to conclude that vitamin D might influence immune responses to infections.

Gee… you think?! Isn’t that what many of us have been saying all along!? But since this information is crucial for supporting your health in the weeks and months ahead, let’s talk a little more about it…

Calming the cytokine storm  

The latest study comes from researchers at Northwestern University. And it found that the risk of severe COVID-19 infection was nearly 16 percent lower among patients with normal levels of vitamin D, compared to deficient levels.

And get this—other research notes that Spain and Northern Italy had high rates of vitamin D deficiency, even though they experience high levels of sun exposure. (As you know, these countries also hold some of the highest rates of COVID-19 infections and deaths in the world.)

Meanwhile, countries like Norway, Finland, and Sweden further north had higher levels of vitamin D—despite a much lower level of sun exposure. And lower levels of COVID-19 infection and death to go with it.

Why? Presumably because the folks up north are encouraged to take vitamin D supplements.

Now, you know how I feel about vitamin D. It’s been the main supplement I’ve recommended for natural defense against any virus since day one. (For additional ways to help boost your immune system in the age of coronavirus, and every day, check out my Complete Guide to Year-Round Immunity.)

And that’s specifically because of the powerful role it plays in lowering inflammation and modulating the immune system. (Extreme inflammatory reactions called “cytokine storms” have been implicated in the most serious cases of COVID-19.)

But as per usual, you can’t really count on the rest of the world to use this kind of common sense. Instead, they’re all jumping on the bandwagon with the naysayers. (You know, the same people who are cheering on an untested vaccine that we’ll likely wait months for, rather than weighing other options as our best hope for recovery).

Adequate isn’t enough

You may have also noticed that all the researchers and clinicians out there are saying that people should have their blood levels tested before they “take their chances” supplementing with vitamin D.

But let me tell you something… In my entire career, I’ve only had two patients optimal levels of vitamin D before they started supplementing.

And don’t forget: There’s a big difference between “adequate” levels and “optimal” levels. Most mainstream doctors consider a level of 30 ng/mL to be “adequate.” But that’s the bare minimum your body needs to keep your bones from disintegrating. Vitamin D’s long roster of benefits don’t really kick in until levels reach 80 to 90 ng/mL. That’s optimal.

And to reach those optimal levels, you need much more than the 400 IU daily vitamin D supplement dose most doctors recommend (if they recommend supplementing at all). Which is why I continue to recommend at least 2,000 to 5,000 IU of D3 daily. (Though, as I’ve explained before, I take 10,000 IU daily myself. And as long as your blood levels are screened regularly, that’s a perfectly safe—and in many cases, necessary—dosage to get you where you need to be.)

Nonetheless, it’s reassuring to see countries around the world recommending that their citizens increase their daily dose of vitamin D—even if it took a pandemic to get there. And maybe, eventually, the U.S. National Institutes of Health will get on board, too.


“Vitamin D: A Low-Hanging Fruit in COVID-19?” Medscape Medical News, 05/17/2020. (