What problems does vitamin D deficiency cause? There is a blood test which can measure how much vitamin D is in your body. Talk with your health care provider if you are at risk for vitamin D deficiency. People who take medicines that affect vitamin D metabolism, such as cholestyramine (a cholesterol drug), anti-seizure drugs, glucocorticoids, antifungal drugs, and HIV/AIDS medicines.People with some lymphomas, a type of cancer.People with sarcoidosis, tuberculosis, histoplasmosis, or other granulomatous disease (disease with granulomas, collections of cells caused by chronic inflammation).People with hyperparathyroidism (too much of a hormone that controls the body's calcium level).People with chronic kidney or liver disease.People who have had gastric bypass surgery.People who have obesity, because their body fat binds to some vitamin D and prevents it from getting into the blood.People with disorders such as Crohn's disease or celiac disease who don't handle fat properly, because vitamin D needs fat to be absorbed.People with dark skin, which has less ability to produce vitamin D from the sun.
Older adults, because your skin doesn't make vitamin D when exposed to sunlight as efficiently as when you were young, and your kidneys are less able to convert vitamin D to its active form.If you are breastfeeding, give your infant a supplement of 400 IU of vitamin D every day. Breastfed infants, because human milk is a poor source of vitamin D.
Some people are at higher risk of vitamin D deficiency: