Vitamin D deficiency means that you do not have enough vitamin D in your body. Vitamin D is unique because your skin actually produces it by using sunlight. Fair-skinned individuals and those who are younger convert sunshine into vitamin D far better than those who are darker-skinned and over age 50.
Vitamin D is one of many vitamins our bodies need to stay healthy. This vitamin has many functions, including:
Getting enough vitamin D may also play a role in helping to keep you healthy by protecting against the following conditions and possibly helping to treat them. These conditions can include:
You can get vitamin D in a variety of ways. These can include:
There are health benefits of sunlight. Vitamin D is produced when your skin is exposed to sunshine, or rather, the ultraviolet B (UV-B) radiation that the sun emits. The amount of vitamin D that your skin makes depends on such factors as:
Vitamin D doesn’t occur naturally in many foods. That’s why certain foods have added vitamin D. In fact, newer food nutrition labels show the amount of vitamin D contained in a particular food item.
It may be difficult, especially for vegans or people who are lactose-intolerant, to get enough vitamin D from their diets, which is why some people may choose to take supplements. It is always important to eat a variety of healthy foods from all food groups. The vitamin content of various foods is shown in the following table.
Vitamin D content of various foods
|Food||Vitamin D content in International Units (IUs) per serving|
|Cod liver oil, 1 tablespoon||1360|
|Swordfish, cooked, 3 ounces||566|
|Salmon (sockeye) cooked, 3 ounces||447|
|Tuna, canned in water, drained, 3 ounces||154|
|Orange juice fortified with vitamin D, 1 cup||137|
|Milk, vitamin-fortified, 1 cup||115-124|
|Yogurt, fortified with 20% of the daily value of vitamin D, 6 ounces||80|
|Sardines, canned in oil, drained, 2 sardines||46|
|Liver, beef, cooked, 3 ounces||42|
|Egg yolk, 1 large||41|
|Cereal, fortified with 10% of the daily value of vitamin D, 1 cup||40|
|Cheese, Swiss, 1 ounce||6|
Source: Vitamin D. Health Professionals. Dietary Supplement Fact Sheet. National Institutes of Health. Office of Dietary Supplements. August 7, 2019.
It is important to check product labels, as the amount of added vitamin D varies when it is artificially added to products such as orange juice, yogurt and margarine.
In healthy people, the amount of vitamin D needed per day varies by age. The chart below shows the often-cited recommendations of the Institute of Medicine, now the Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine. It is important to know that these are general recommendations. If your doctor is checking your blood levels, he or she might recommend higher or lower doses based on your individual needs.
If you have osteoporosis, your doctor might suggest a blood test of your vitamin D levels. The amount of vitamin D supplement can be customized for each person, based on the results. For many older patients, a vitamin D supplement containing anywhere between 800 to 2000 IUs daily, which can be obtained without a prescription, can be both safe and beneficial. It is important to speak with your doctor about your individual needs.
|People by age||Recommended dietary allowance (IU/day)||Upper level intake (IU/day)|
|Infants 0-6 months*||400||1,000|
|Infants 6-12 months*||400||1,500|
|Children 1-3 years old||600||2,500|
|Children 4-8 years old||600||3,000|
|People 9-70 years old||600||4,000|
|People over 70 years old||800||4,000|
|Females 14-50 years old, pregnant/lactating||600||4,000|
*refers to adequate intake vs recommended dietary allowance of the other age groups.
Vitamin D deficiency can be caused by specific medical conditions, such as:
Yes. Vitamin D levels can be lowered by certain medications. These include:
Always tell your doctor about the drugs you take and any vitamin D supplements or other supplements or herbs/alternative health products that you take.
Severe lack of vitamin D causes rickets, which shows up in children as incorrect growth patterns, weakness in muscles, pain in bones and deformities in joints. This is very rare. However, children who are deficient in vitamin D can also have muscle weakness or sore and painful muscles.
Lack of vitamin D is not quite as obvious in adults. Signs and symptoms might include:
Your doctor can order a blood test to measure your levels of vitamin D. There are two types of tests that might be ordered, but the most common is the 25-hydroxyvitamin D, known as 25(OH)D for short. For the blood test, a technician will use a needle to take blood from a vein. You do not need to fast or otherwise prepare for this type of test.
There are some differing opinions about what levels of vitamin D work the best for each person. Laboratories might use different numbers for reference. Please discuss your results with your doctor.
Doctors do not usually order routine checks of vitamin D levels, but they might need to check your levels if you have certain medical conditions or risk factors for vitamin D deficiency. Sometimes vitamin D levels can be checked as a cause of symptoms such as long-lasting body aches, a history of falls or bone fractures without significant trauma.
The goals of treatment and prevention are the same—to reach, and then maintain, an adequate level of vitamin D in the body. While you might consider eating more foods that contain vitamin D and getting a little bit of sunlight, you will likely be told to take vitamin D supplements.
Vitamin D comes in two forms: D2 and D3. D2, also called ergocalciferol, comes from plants. D3, also called cholecalciferol, comes from animals. You need a prescription to get D2. D3, however, is available over the counter. It is more easily absorbed than D2 and lasts longer in the body dose-for-dose. Work with your doctor to find out if you need to take a vitamin supplement and how much to take if it is needed.
Yes. You can get too much vitamin D if you overdo the supplements. Interestingly, you cannot get too much vitamin D from the sun. Vitamin D toxicity is, thankfully, quite rare but can lead to hypercalcemia and together the symptoms can include:
Do not take higher-than-recommended doses of vitamin D without first discussing it with your doctor. However, your doctor might recommend higher doses of vitamin D if he or she is checking your blood levels and adjusting your dose accordingly. Also, be cautious about getting large doses of vitamin A along with the D in some fish oils. Vitamin A can also reach toxic levels and can cause serious problems.
The goals of treating and preventing the lack of vitamin D of treatment and prevention are the same—to reach and keep an adequate level of vitamin D in the body. Your healthcare provider will let you know if you need to take or keep taking vitamin D supplements. If so, they will also let you know how much you should take. You might also want to consider:
Eating more foods that contain vitamin D: See the vitamin D food sources table included in this article. Keep in mind that foods alone usually don't meet the daily recommended levels of vitamin D.
Getting some exposure to sunshine—but not too much: Exactly how much sun exposure is needed isn’t clear. 10 to 15 minutes of sun exposure two to three times a week to the face, arms, legs or back may be all that is needed to absorb a suitable amount of vitamin D. You might need more sun exposure (especially in early spring and late fall) if:
The use of sunscreen, and standing behind a window, prevents vitamin D from being produced in the skin. However, you should remember that too much sunshine increases the risk of skin cancer and ages the skin. That is why taking an appropriately dosed D supplement is far safer than intentionally getting routine sun exposure.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 10/16/2019