Boning up on D

History has taught us to load up on calcium for bone health, but take note vitamin D is quickly emerging as the superstar bone nutrient. Vitamin D is in fact necessary for the absorption of calcium. So if we don’t get enough of the D, it won’t matter if we are getting enough calcium. At its worst vitamin D deficiency can result in rickets and stunted growth in children, osteomalacia -weakened muscles and bones - and osteoporosis in adults.

Traditionally vitamin D is known as the sunshine vitamin because the body can synthesize it when the sun hits our skin. So theoretically we should be able to get all we need from the sun, as there aren’t a lot of food sources of vitamin D.

Unfortunately, sunscreen has been getting in the way of that source. History has also taught us to wear sunscreen to protect us from skin cancer. That practice, however, blocks out the suns’ ultraviolet rays that are needed to trigger vitamin D production in the body. There is a current debate amongst dermatologists and vitamin D experts over safe sun exposure. The dermatologists say sunscreen sunscreen sunscreen to protect protect protect our delicate skin from the suns’ harmful rays. While the vitamin D experts claim the risk from lack of vitamin D is much higher than the risk for getting skin cancer, so spend a little time in the sun

Ironically chronic vitamin D deficiency has been linked to a reduced risk of some cancers. And it doesn’t stop there; the big D appears to be protective against diabetes, high blood pressure, and heart disease, perhaps even multiple sclerosis. The current recommendation for vitamin D ranges from 200 to 400 International Units (IU). But the consensus is that isn’t enough. To obtain the vitamins’ protective effects researchers advise 1,000 to 2,000 IUs a day. That’s a big jump.

Bottom-line: don’t be quite so afraid of the sun. The recommendation is to make sure you get adequate sunlight but of course avoid burning. So what does that mean? How much sun? It is longer for some than it is for others. The darker your skin the more time in the sun you will need, 2-4 times more than that of a pale skinned person. The general rule of thumb from Vitamin D enthusiasts is to get just enough sun before your skin changes color i.e. before you get pink if you are light skinned, about 10 to 20 minutes. If you live in the Northern United States the sun’s rays aren’t strong enough year round to trigger vitamin D production in the skin so make sure you get a little sun in this summer to carry you through the winter months. But do put your sunscreen on after you’ve been in the sun for a few minutes, and before you start to change color.

And of course there are a few food sources you can rely on; milk is a good source because it is fortified with vitamin D (most soy and rice milks are now too, but you have to read labels to make sure). Yogurt may or may not be fortified so again check labels. Fatty fish like salmon, mackerel, sardines, shrimp and tuna are excellent sources. Egg yolks and mushrooms have a little. Look for fortified cereals and orange juice to boost your intake.

You can also take a supplement. The American Academy of Pediatrics recommends 200 IU supplements for at-risk children and adolescents. There hasn't been an official updated recommendation for adults yet, but keeping it under 2,000 IUs a day is considered safe.

Go out and get your D!

(photo courtesy of keone)