Health Library

What Is Vitamin D?

Vitamin D is a nutrient that helps the body take in calcium from the foods that we eat. Together, calcium and vitamin D build bones and keep them strong. Vitamin D also plays a part in heart health and fighting infection.

Why Do Kids Need Vitamin D?

Kids need vitamin D to build strong bones. Vitamin D also helps bones heal after an injury or surgery.

Where Does Vitamin D Come From?

The Sun

Our bodies make vitamin D when our skin is exposed to the sun. It’s hard to get enough vitamin D from the sun, though. Most kids and adults spend lots of time indoors at school and work. When outdoors, it’s important to protect skin to prevent skin cancer and skin damage from too much sun exposure.

Food

Very few foods have vitamin D naturally. The foods with the most are fatty fish (like salmon and tuna), liver, eggs and fish oils. Kids don’t eat these foods a lot. That’s why food companies add vitamin D to milk, yogurt, baby formula, juice, cereal, and other foods.

Adding vitamin D to foods is called “fortifying.” It’s helpful, but it still may not be enough.

Supplements

To get enough vitamin D, children often need to take a multivitamin with vitamin D or a vitamin D supplement. Vitamin D is sometimes labeled as vitamin D3.

You can buy vitamin D pills, gummies, chewables, liquids, and sprays in stores without a prescription. Ask your child’s health care provider for advice on choosing the right one.

How Much Vitamin D Does My Child Need?

Vitamin D is measured in international units (IU).

• Babies younger than 1 year old need 400 IU of vitamin D a day. Baby formula has 400 IU per liter, so babies who drink at least 32 ounces of formula each day get enough. If your baby drinks only breast milk or gets less than 32 ounces of formula each day, ask your health care provider about giving your baby a vitamin D supplement.
• Kids older than 1 year need 600 IU or more of vitamin D a day. Health care providers often want healthy kids to take 600 to 1,000 IU daily.

Some kids might need more vitamin D, such as those who:

• have certain medical problems (for instance, obesity, celiac disease, cystic fibrosis, multiple fractures, or bone pain)
• are healing from bone surgery (such as after fusion surgery for scoliosis)
• are taking medicines (like anti-seizure medicines) that block the way the body uses vitamin D

Your health care provider can talk to you about whether your child needs a vitamin D supplement.

How Can I Help My Child Get Enough Vitamin D?

Because vitamin D is so important, you’ll want to be sure your child gets enough. Giving your child a daily supplement or a multivitamin with vitamin D is the easiest way to do this.

Health care providers might order a blood test if they think a health problem is keeping a child from getting enough vitamin D. If doctors don’t think your child has a health problem, there’s no need for a blood test.

What About Calcium?

Vitamin D helps the body absorb calcium, a building block for strong bones. Unlike with vitamin D, kids usually can get enough calcium from food. High-calcium foods include milk, cheese, and yogurt. Food makers often fortify foods like cereal, bread, or juice with calcium.