The Vitamin D Facts

So what are the causes of vitamin d deficiency?  Don’t we get enough of it in our foods?  What about the multivitamins we take?  (Always assuming we take them, on a regular basis.)  And then again, doesn’t the sun provide enough vitamin d for us?

How can we be deficient in vitamin d, between food, supplements and sunshine?  I’ve discussed it a little in my vitamin d facts post, but let’s take another look.

What Amounts Do Our Bodies Need?

Before we talk about the causes, let’s look at how much our bodies need.  This way, you’ll be able to understand the causes much better.

Way back in the early 1900’s, rickets was a all-too-common disease.  Rickets is basically a case of too-soft bones that can bend and warp — and break.  It was especially prevalent in the children of that time.

In 1914, Dr. E.V.McCollum discovered that cod liver oil contained vitamin d; here was a supplement people could use.  But at what dose?  It was rather trial and error for awhile.

The, in the 1940’s, the current standard of 400 IU was set, because it was determined that a small amount of cod liver oil was enough to prevent rickets in a baby.  That’s fine for a baby and a young child, but as we get older, our bones get larger.  Is 400 IU enough for a teen, adult or senior — especially when you consider the epidemic of osteoporosis?

In the American Journal of Clinical Nutrition, Drs. Robert Heaney and Michael Holick argued for a weight-based calculation, instead of a one-size-fits-all 400 IU.  Applauded by the nutritional community, and in line with what the body’s d levels should be, the recommendation has not passed the FDA.

(Can you imagine the labeling difficulties for foods containing vitamin d?)

In the book The Vitamin D Cure, Dr. James E. Dowd suggests a method using weight calculation, like Drs. Heaney and Holick recommend.  Now obviously, how much you take also depends on how much time you spend (or don’t spend) in the sun.  But as a minimum, for the person who rarely is out in the mid-day sun, supplementation at the rate of 20 IU per pounds of body weight is the dosage to shoot for.  This means that a person 150 pounds would need to take 3.000 IU a day to get the body to a good vitamin d level.

The Causes of Vitamin D Deficiency

OK, now you know how much your body needs; for argument’s sake, let’s say it’s 2,000 IU.  Where are you going to get it?

Vitamin d is known as the “sunshine vitamin” and it truely is.  Our bodies use UVB rays to convert to vitamin d in our bodies.  Pretty neat!

But here’s the problem.  You’d need to expose a large portion of your body (think swimsuit, or at most shorts and a t-shirt) to the sun at 3 times a week.  For how long depends on how dark your skin is to start with; it could be anywhere from 15 minutes to 40 minutes.  No sunscreen allowed during the time, because sunscreen prevents UVB rays, which is what your body needs to create vitamin d.

Also keep in mind that the vast majority of people aren’t about to get dressed in shorts and a t-shirt in the middle of winter to sunbathe!

And let’s face it; anyone who lives in a hot climate stays out of the sun and in the cool air conditioning!

OK, it seems that sunshine is out for getting the vitamin d our bodies need.  What about food?

Vitamin D and Food — Surprising Facts

I challenge you to go into your cabinets and refrigerator to look for foods that contain more than 5 IU of vitamin d on the label.  Not counting milk or breakfast cereal, how many did you find?  If you’re like me, you found none.

The fact is, unless a food is fortified with vitamin d, it very likely doesn’t have any!  Our bodies were designed to get this vitamin from sunlight, and it’s not present in any appreciable quantities in food.

Which begs another question — how often do you drink a few glasses of vitamin d fortified milk in a day?  How many servings of breakfast cereal do you eat on a daily basis?  My guess is that unless you’re downing an awful lot of Total, you aren’t getting much at all.

If you aren’t getting it from sunshine or from your food, how do you know if you’re deficient?  You can check out the vitamin d deficiency symptoms post for a list.

Vitamin D Supplements

So that leaves us with vitamin d supplements.  I just went to some websites to look at how much vitamin d the two most popular brands of multivitamins (Centrum and One-a-Day) provide.

The winner was One-a-Day Women’s 50+ Advantage, at 800 IU a serving.  Sorry guys, you only get 400 IU, even in the Men’s 50+ Advantage.

The moral of this story — don’t depend on a multivitamin to give your body everything it needs.  Certainly, it’s better than nothing, but your body is still running in the deficient mode. 

Your best bet is a separate vitamin d supplement to give you all that you need.  And the good news; there are plenty out there and they are quite inexpensive!  To get an idea of just how little they cost, here’s the one my husband and I use:

Vitamin D-3 1000 IU

I think you’ll agree, that’s a lot of protection for a very small price!

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