How Important is Vitamin D?

What's the most important vitamin for you? New studies show it's vitamin D.

"It turns out most of us are vitamin d deficient. Getting enough could prevent heart disease, stroke, and numerous other things; in short save your life," Dr. Hensel said.

Bonnie Everhart has learned she needs to check to check her vitamin D levels. 

 "My grandmother had a history of osteoporosis and my mother has a history of breast cancer," Everhart said. 

It's a valid concern, as more research points to chronic health problems related to low vitamin D. 

"Those populations that have vitamin d deficiency actually have higher rates of these kinds of cancers, like breast cancer and prostate cancer," Dr. Roberta Lee said. 

Other studies link insufficient vitamin D to a range of conditions, from multiple sclerosis and diabetes to heart disease and high blood pressure. Inadequate "D" can even start haunting you in the womb.

"Pregnant women who are vitamin d deficient, especially in their late trimesters, have been shown nine years later to have children who have very low bone density," Dr. Lee said. 

Its easy to get tested.

"Ask your doctor to measure the 25 hydroxy vitamin d level. That's the active D3 level. That's the one you want to find the answer to. If it's under the number of 20 nanograms per milliliter, then you are in a deficient zone," Dr. Lee said.

While you can get vitamin D from some foods like wild salmon and fortified milk, it isn't always enough.  Use supplements, as well.

"Most of the time for an adult, somewhere between 1,000 to 2,000 international units on a daily basis of vitamin D3 is enough to have adequate replacement." 

But too much vitamin D can cause side effects; the simple solution; get it checked regularly.
"It's really important for us to know what my vitamin d level, and if it's, you know, to work with it, whether i need supplements or i can cut down," Everhart said. 

Since vitamin D is naturally produced by exposure to sunlight, the question is: Why not just get out in the sun?

"Ten to 15 minutes of sun on your bare legs and arms, once a day, is probably going to give you enough u-v exposure to produce vitamin D. But, this isn't a free pass to skip sunscreen. Slather it on after your brief sun allotment is up and do check your blood levels to make sure," Dr. Hensel said.


Currently, health experts say adults 19 to 50 should get 200 IU of vitamin D every day.

Vitamin D may play a role in many different conditions, like heart attacks, diabetes, multiple sclerosis and cancer.

Doctors may recommend a blood test to measure your 25-hydroxyvitamin D level.

For more details, refer to our comprehensive research summary.

For general information on vitamin D:

American Dietetic Association,
NIH, Office of Dietary Supplements,

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