Vitamin D, or calciferol, is a fat-soluble vitamin that you can find in some foods and supplements. It’s also produced when ultraviolet (UV) rays from sunlight strike the skin and trigger vitamin D synthesis. Vitamin D plays an important role in several functions within the body, and having too much or too little of it can cause problems.

Read on to learn more about Medicare’s coverage for a vitamin D test, why you may need one, and treatments that could be recommended.

Why is vitamin D important?

Vitamin D does a variety of things in the body. Primarily, it plays a big role in regulating different cellular functions to support healthy bones, muscles, and brain cells. It can also reduce inflammation, promote immune function and metabolism, facilitate calcium absorption, and modulate cell growth.

Some studies suggest maintaining appropriate vitamin D levels can even have a positive impact on mental health and wellness.

Without vitamin D, bones can become think, brittle, or misshapen, which leads to osteoporosis. Vitamin D can also help reduce the risk of falls in older individuals and prevent disease such as diabetes, heart disease, and certain types of cancer.

How do you get vitamin D?

Vitamin D occurs naturally in some foods such as fatty fish, egg yolks, beef liver, and cheese. In the U.S., vitamin D is also added to some foods including milk, cereal, and orange juice.

Your body can also produce vitamin D when exposed to sunlight.

Because some individuals may not be able to maintain adequate levels of vitamin D through diet and sunlight, some doctors recommend a daily multivitamin supplement to ensure the body gets enough.

Read more about how to get more vitamin D.

What causes a vitamin D deficiency?

There are several risk factors that can affect the body’s ability to produce or absorb enough vitamin D, including getting older. In fact, the skin’s ability to synthesize vitamin D declines with age, leaving older adults at more risk for a deficiency. Older adults also tend to get less vitamin D through natural food sources.

Other factors that can put you at high risk include obesity, darker skin pigmentation, or medical conditions that limit fat absorption such as chronic liver disease, ulcerative colitis, and cystic fibrosis. Other health conditions that can cause vitamin deficiency include chronic kidney disease, Chron’s disease, celiac disease, nutrient absorption issues related to gastric bypass surgery, hyperparathyroidism, and sarcoidosis.

Additionally, some medications like steroids, anti-seizure drugs, and stimulant laxatives may prevent your body from absorbing and processing vitamin D properly.

Symptoms of a vitamin D deficiency

Some symptoms that may indicate low levels of vitamin D include fatigue, hair loss, mood swings, muscle aches, back pain, or frequent infections or sickness. Wounds that are slow to heal may also indicate a deficiency.

If you’re experiencing any of these symptoms, your doctor may recommend a screening for vitamin D deficiency.

What is a vitamin D test?

A vitamin D test measures the level of vitamin D in your blood to make sure you have enough for your body to work well. This test is a blood test, so the provider will take a blood sample from a vein in your arm using a small needle. You don’t need any special preparations for a vitamin D test, and it typically takes less than five minutes.

Other names for a vitamin D test include 25-hydroxyvitamin D, 25(OH)D, cholecalciferol test, ergocalciferol test, calcidiol test, vitamin D2 test, or vitamin D3 test.

Medicare coverage for vitamin D testing

Vitamin D testing may not be used for a routine screening. However, Medicare Part B (medical insurance) covers clinical laboratory tests, including blood work, if considered medically necessary and ordered by your provider. This may include a vitamin D screening if you meet certain conditions.

Note that vitamin D screenings aren’t typically performed with routine blood work, so your provider may need to prove medical necessity before it’s covered by Medicare. For example, they may need to provide documentation like proof of a medical condition that causes vitamin D deficiency, or a list of symptoms.

If approved, the test must be done in a Medicare-approved lab.

If you have a chronic deficiency, Medicare Part B may cover additional blood tests to help monitor the condition. Or, if your provider suspects an underlying condition, Medicare may approve additional screenings or lab work to help find a diagnosis.

After meeting the Part B deductible, you may owe 20% of the Medicare-approved amount out-of-pocket. Medicare will cover the remaining 80%.

Medicare Advantage plans (Part C) will also cover medically necessary vitamin D testing ordered by your provider. And if you have Medicare Supplement Insurance, it may cover your share of the cost, depending on which plan you have.

Treatment for vitamin D deficiency

If you have a vitamin D deficiency, the treatment will depend on your age, the severity of the deficiency, and whether your provider may suspect an underlying cause.

Most of the time, your provider will recommend an over the counter (OTC) or prescription supplement of vitamin D2 or vitamin D3, which can help increase the levels of vitamin D in your body. After six to eight weeks of treatment, your doctor may then lower the recommended dosage.

Note that although vitamin D supplements are safe when taken appropriately, it is possible to take too much vitamin D. If you take more than 4,000 IU daily, you may experience weakness, confusion, constipation, decreased appetite, nausea or vomiting, or weight loss. In rare cases it can cause hypercalcemia. Taking any supplements as prescribed or recommended will help prevent this.

Your provider will likely request that you get regular blood tests to monitor your levels so that they can adjust your dose if necessary.

Does Medicare cover vitamin D supplements?

If your provider recommends prescription vitamin D supplements, they may be covered by your Part D prescription drug plan, or a Medicare Advantage plan that includes prescription drug coverage. You can check your plan’s formulary to learn if these supplements are covered and how much they will cost.

Original Medicare does not cover over the counter vitamin D supplements like those you’d purchase at a grocery store or drug score. However, some Medicare Advantage plans have additional benefits like an allowance for OTC products, including nonprescription vitamin D supplements. Check with your plan to learn more.

Are you looking for a new Medicare plan? Our Find a Plan tool makes it easy! Just enter your zip code to review the costs and benefits of Medicare plans in your area.

Additional resources

• ClearMatch Medicare: Find a Medicare Plan
• Medicare.gov: Costs