What Does It Mean If I Have a Vitamin D Level of 12?

Your body produces vitamin D, also called the sunshine vitamin, after exposure to the sun's ultraviolet rays. That may seem like the only excuse you need to head outdoors, but organizations like the American Academy of Dermatology urge you to consider the skin risks involved in soaking up the sun. Still, meeting your body's needs for vitamin D can prove difficult if you're avoiding UV light. If you've recently learned your vitamin D level stands at 12 ng/mL, it's important to work with your doctor on reaching an adequate level.

The 25-hydroxy vitamin D test allows physicians to assess your level of the vitamin. It is the best indicator for vitamin D, according to the Office of Dietary Supplements. A reading of 20 ng/mL to under 50 ng/mL is considered acceptable and safe for the general population. A level of 12 ng/mL, however, indicates that your vitamin D level is too low. In fact, 12 ng/mL and below is a sign of deficiency, which can have major health repercussions.

With a vitamin D level of 12 ng/mL, you're at risk for a number of conditions affecting the bones because of the deficiency's effect on calcium absorption. Vitamin D is an important hormone for bone health; a lack of it affects your intestines' ability to absorb calcium, which is the chief mineral component of bones. This puts you at risk for developing soft bones that easily fracture, a condition called osteomalacia. The condition is known as rickets when it occurs in children. You may also be at risk for cardiovascular problems, in addition to bone diseases like osteoporosis, according to Dr. Edward Giovannucci of the Harvard School of Public Health.

With a level as low as 12 ng/mL, you likely belong to one or more high-risk groups. These include people who have limited access to sunlight due to illness, their job or their location. Being an older adult also puts you at risk for deficiency because your skin is unable to make vitamin D as well. Having dark skin also is a risk factor, but the Office of Dietary Supplements acknowledges that it's unclear how lower levels affect those with darker pigmentation. Following a restrictive diet or having a malabsorption disorder can contribute to deficiency as well.

Your doctor will use your test results to develop a treatment plan and address the underlying cause of the deficiency. You will likely begin taking a vitamin D supplement to improve your level. You may need to take as much as 3,000 to 4,000 IU a day if you're in one of the high-risk groups, according to Dr. Giovannucci. Don't take it upon yourself to supplement because too much vitamin D can be dangerous. It's also vital that you discuss any medications or supplements you're currently taking -- some, such as cholesterol-lowering drugs and steroids, can interact with vitamin D.