What is a vitamin D deficiency? — A vitamin D deficiency is when you do not have enough vitamin D in your body. This is a problem, because the body needs vitamin D to absorb calcium and for other important jobs.

People who do not have enough vitamin D can:

��Have weak or soft bones, which can break easily or change in shape

��Have weak muscles, which makes them more likely to fall

Is there a test for vitamin D deficiency? — Yes. Your doctor or nurse can do a blood test to see if you have enough vitamin D. But you might not need this test. Doctors measure vitamin D levels only in people who are at risk for a vitamin D deficiency. This includes people who:

��Spend most or all of their time indoors (for example, because they are in a nursing home)

��Have medical problems (such as Celiac disease) that make it hard from them to absorb vitamin D

��Have a condition called “osteoporosis,” which makes bones weak

��Broke a bone too easily, such as by falling down

What foods and drinks have vitamin D? — Foods and drinks that have a lot of vitamin D include (figure 1):

��Milk, orange juice, or yogurt with vitamin D added

��Cooked salmon or mackerel

��Canned tuna fish

��Cereals with vitamin D added

��Cod liver oil

People’s bodies can also get vitamin D from the sun. The body uses sunlight that shines on the skin to make vitamin D.

What are supplements? — Supplements are pills, capsules, or liquids that have nutrients in them. Supplements are another way people can get vitamin D.

Do I need to take vitamin D supplements? — Experts recommend that most adults take supplements that have 800 international units of vitamin D a day. People who do not get enough vitamin D from their food or from the sun might need to take even more.

If your doctor recommends that you take vitamin D supplements, ask him or her which type, how much, and when to take the supplements.

The type and dose of supplement that is right for you will depend on your medical problems and the other medicines you take.

It is important not to take too much vitamin D. Taking too much vitamin D can make you sick.