What Is the Normal Range for Vitamin D in a Blood Test?

Your body uses vitamin D for maintaining healthy bones and effectively absorbing calcium. Not having enough vitamin D in your system may raise your risk of osteoporosis, bone malformations, cancer, inflammation and suppressed immunity. A simple blood test can give you accurate results and help you determine if your vitamin D levels are in the healthy range.

Your body has different forms of vitamin D. The National Institutes of Health reports that the 25-hydroxy vitamin D test is the most accurate measuring tool for determining whether you have enough vitamin D in your system. According to the Institute of Medicine, the optimum range of 25-hydroxy vitamin D in the blood is 20 to 50 nanograms per milliliter, abbreviated ng/mL. Less than 20 ng/mL is inadequate, but more than 50 ng/mL may also put your health at risk. Discuss your results with your doctor if you have any concerns about your vitamin D level.

The Institute of Medicine recommends 600 international units, or IU, per day of dietary vitamin D for adults through age 70 and 800 IU per day thereafter. You can get vitamin D three ways: sun exposure, the food you eat and supplements. Sun exposure can be problematic because of the associated risk of skin cancer. Vitamin D-fortified, low-fat milk and dairy products, tuna, salmon and eggs are good sources of this important nutrient.