Why you shouldn’t stop taking vitamin D — even in the summertime

Now that we’re entering the time of year when time spent in the sun increases significantly, you might consider taking a “summer vacation” from supplementing with vitamin D.

But I’m here to tell you that’s a big mistake.

There is simply no reason NOT to keep taking your vitamin D supplements year-round. And three very good reasons you should.

First, even with summer sun exposure, most people still don’t get enough vitamin D to reach optimal blood levels of this critical nutrient.

Second, since vitamin D is a fat-soluble vitamin, you can and should supplement year-round to store it away (literally) for a rainy day.

Third, there is no risk of “overdose.” Even at this time of year, your skin cannot make too much vitamin D from sun exposure, since there is an automatic, biological “shut-off” mechanism when you get enough.

Still, I hear from well-meaning people who question the safety of vitamin D supplementation. It doesn’t help that editors of medical journals stay on the fence, despite publishing hundreds of studies showing the clear benefits vitamin D supplementation. This wishy-washy stance has consequently been drilled into doctors’ heads for decades.

Plus, even the so-called experts underestimate how much vitamin D you really need daily…

RDA for vitamin D off by a factor of 10

As you might recall, I revealed how two different teams of researchers discovered the Institute of Medicine’s (IOM) Recommended Daily Allowance (RDA) for vitamin D is off by a factor of 10. That means men and women need 10 times more vitamin D than the puny amount the IOM recommends to ward off diseases related to vitamin D deficiency.

This discrepancy isn’t just a rounding error. It means the decimal point must move one place over. And it represents a huge, astronomical mistake.

So, how much do you really need?

I recommend everyone take 10,000 IU daily of vitamin D year-round. And remember, that dose may sound high, but it’s really not high at all when you compare it to typical dosage amounts of other common nutrients in the more standard mass terms of milligrams and micrograms.

Now, some people I know take 50,000 IU capsules of vitamin D once a month. I never recommend 50,000 IU capsules. You’re much better off taking a lower, daily dose. But is this dose dangerous?

Well, if your child or grandchild gets into a bottle of capsules of this size, it could potentially cause side effects that could require urgent medical attention.

But I find it ironic, the same naysayers who cite the hypothetical dangers of vitamin D overdose in children will happily hand out a deadly drug to their own kids—acetaminophen. Sure, the colorful capsules and liquid might look like candy, but acetaminophen has been associated with some terrible stuff:

  • It’s the leading cause of liver toxicity and fatal liver failure
  • It’s the leading cause of calls to the Poison Control Centers across the U.S.
  • It causes 56,000 emergency room visits, 2,600 hospitalizations, and an average of 458 deaths a year.

The first time I investigated a death related to acetaminophen, I reported it to the “authorities.” But I was told that’s just “business as usual” when it comes to acetaminophen.

So, by comparison, how many die from vitamin D “overdoses”?

According to the Vitamin D Council, about 15,000 people in the U.S. took an “overdose” of vitamin D between 2001 and 2014.

And nobody died.

And only five people developed clinical side effects.

During the same 13-year period, nearly 6,000 people died from acetaminophen, including a number of toddlers.

By any reasonable measure, vitamin D is safe and has a staggering list of benefits associated with it. So — go ahead and keep taking a daily dose of 10,000 IU year-round.

You can now find vitamin D in a convenient liquid form together with the potent marine carotenoid astaxanthin. That’s a bonus for brain health, hearing, and vision. (You can find more information about astaxanthin on my website, www.DrMicozzi.com.)

Also, make sure to ask your doctor at your next check-up to test your vitamin D levels with a 25(OH)D test. Ideally, you want your levels to be between 50 nmol/L and 75 nmol/L. (That’s nanomoles, which are tiny concentrations relative to other nutrients.)


“How safe is Vitamin D?,” Vitamin D Council (www.vitamindcouncil.org) 12/18/2017