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Vitamin D Research Raises New Questions

Vitamin D Not A Silver Bullet
After All? 


vitamin-d-and-depression-01 (Photo credit: Life Mental Health)

A recent study by Johns Hopkins researchers finding that there is indeed an upper level of benefit with vitamin D blood levels is likely to put vitamin D proponents in quite a snit.

Actually, I’m a vitamin D proponent as well – I supplement with it daily and try to get it optimally from prudent sun exposure, nutrition and diet.

But I’ve also written about the limitations of its benefits (see bottom of page to sign in for a free copy of my eBook on the subject).

This latest study vindicates my position that, as with most things, there can be too much of a good thing (including healthcare – see Our Healthcare Sucks). The general rule for both diet and supplements should be to avoid extremes. With supplements, this means no mega-doses.

For vitamin D, even the 5,000 IU (International Unit) doses that are newly popular may be excessive for many people. The physician considered the leading expert on vitamin D generally recommends 2-3,000 IUs/day except in cases of severe deficiency (see my eBook for details).

And that’s targeting a much higher blood level of vitamin D than the Johns Hopkins researchers found healthful. In fact, the 21 nanograms per milliliter they found to be optimal – with increasing risk for artery hardening, inflammation and other cardiovascular risk above that level – is considered deficient by most vitamin D advocates.

So you can expect a lot of strident protests about these results, and I bet some of it will get pretty ugly. The internet seems to bring out the worst in some people, none more so than the true believers in a cause – aided and abetted by the anonymity it affords. And, of course, if there are careers or other financial interests at stake…well, you know the drill.

Vitamin D Facilitates Calcium Absorption

And now there’s another new study about the risks of excess calcium that may lead to further recriminations.  Calcium is absorbed most effectively in tandem with vitamin D – the lower your vitamin D level, the less calcium you’ll absorb, and vice versa.

Of course, we need calcium for strong bones – the primary reason many postmenopausal women supplement with calcium and vitamin D. But it’s a mixed blessing if the price for harder bones is harder arteries.

And the higher levels of vitamin D advocated so vehemently these days by vitamin D gurus translates into higher levels of calcium in the bloodstream as well.

And this second study suggests this may not be a good thing, with a six-fold greater risk of death from heart attack or heart disease among those with calcium accumulation in  their coronary arteries.

It Is The Sunshine Vitamin

It’s not that vitamin D isn’t healthful – at the appropriate doses, which vary dramatically based on…

  • Your current level of adequacy or insufficiency, 

  • Where you live (i.e., how much you produce naturally with safe skin exposure to the sun’s ultraviolet rays), 

  • Your age and body fat composition (both impede vitamin D production and circulation), 

  • Your skin pigmentation (dark-skinned people produce less vitamin D with sun exposure), and 

  • Your risk for certain diseases that vitamin D helps prevent or, in some cases, may help promote.

And with summer soon upon us, you’ll hopefully get more natural vitamin D with prudent sun exposure. That, too, will vary with the above factors, but 10-15 minutes of mid-day exposure to arms and legs daily – or even a few days a week – is considered adequate for most people (though not for dark-skinned people who’ll need considerably more).

Higher rates of high blood pressure and stroke among African-Americans is thought by many experts to be attributable to their lessened production of vitamin D, especially as they age.

It’s important, of course, that you not be lathered up with sun block lotions during this brief exposure to midday sun (between 11 AM and 1 PM is most beneficial for vitamin D production), as these will also block your ability to absorb the ultraviolet rays needed for vitamin D production.

Apply Some Common Sense
When Applying Your Lotion

Here’s where the dermatologists and skin cancer experts get antsy. While they probably wouldn’t argue with the basic premise that some sun exposure is indeed healthful, their focus is on the damage that too much exposure can cause.

As with most things, there’s a happy medium – a balance of unprotected exposure that’s calibrated based on how many of the above factors apply to you and risky unprotected exposure that exceeds your personal requirements.

The safest route is probably to err on the side of caution and be sure to get enough vitamin D supplementation from your diet and supplements (again, see my free eBook for details on both). There’s a blood test I discuss in the book that can help you monitor your blood level of vitamin D – the goal is to keep it in a healthy range and consistent on a year-round basis.

Given the variability of our exposure to the sun in fall and winter months, this generally will mean increasing your dietary and supplement sources during those months and reducing them in summer months. Consistency of your blood levels of vitamin D year-round may be as important as the absolute blood level itself.

Get Your Vitamin D Wisely

This is by no means an indictment of vitamin D – an essential vitamin (a hormone in reality) that most of us produce too little of without some degree of supplementation. It’s simply a caution to not go overboard. Get your blood level checked – this is a good time to do so before you start building up your blood level with increased sun exposure.

Every 1,000 IUs of vitamin D3 supplements you take can be expected to produce an increase of about 10 nanograms per milliliter in most people, although this too will vary and will taper off with higher doses (i.e., 5,000 IUs is unlikely to produce a 50 nanogram per milliliter increase).

Nor would that be a good thing, at least based on these latest research results.

There’ll be more to come on what’s optimal for vitamin D levels. For now, I’m sticking to my guns about using caution and avoiding the 5,000 IU doses that are the biggest sellers right now.

Few people are likely to benefit with that high a dose – and many are likely to be harmed.

Don’t be one of them.

[kc_background type=”1″]Wanna’ D-bate about D? Weigh in below[/kc_background]

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