Vitamin D is essential for healthy bones and a strong immune system, but it's hard to know if your child is getting sufficient amounts. In fact, research shows about 42 percent of Americans are vitamin D deficient. "Absorbing enough vitamin D has always been challenging for most people who prioritize skin protection over sun exposure, but now with stay-at-home orders, getting vitamin D from the sun is very challenging," says Kecia Gaither, M.D., M.P.H., F.A.C.O.G., director of perinatal services at NYC Health Hospitals/LINCOLN.
Keep reading to learn more about the importance of vitamin D and how to ensure your kid is getting their share—even while social distancing during the coronavirus pandemic.
Why is Vitamin D Important?
Vitamin D has numerous benefits for children and adults alike. It's associated with stronger bones, strengthened immune systems, lower risk for premature birth, and possible disease prevention.
Stronger Bones: Calcium is probably on your radar when it comes to your kid's bone health, but there's something else to think about: Vitamin D. Indeed, the body can only absorb the bone-strengthening mineral when there's vitamin D present, according to the resource published in JAMA Pediatrics. Kids build bone throughout their childhood and adolescence, so getting enough of both calcium and D is critical during that time. In rare cases, kids can fall so short in vitamin D that they develop a condition called rickets, when bones become weak and soft and their legs appear bowed.
Strengthened Immune System: Vitamin D also plays a vital role in the immune system, according to Dr. Gaither. What's more, published research shows that vitamin D blood serum levels of 50 nanograms per milliliter (ng/ml) appears to protect against viral respiratory infection—which is especially important in light of COVID-19.
Lowered Risk of Premature Birth: The benefits of Vitamin D extend to pregnant women. "Research shows the risk of premature birth decreases by 60 percent when vitamin D blood levels are of 40 ng/ml or higher, a level that may be particularly important during COVID-19," says Dr. Gaither.
Disease Prevention: Researchers are also studying whether vitamin D plays a role in the prevention of diseases like cancer and heart disease—though the National Institutes of Health (NIH) says there's not enough evidence to show cause and effect.
How Much Vitamin D Should Children Get?
The American Academy of Pediatrics (AAP) says the optimal amount equates to 400 International Units (IU) per day of vitamin D for infants under 12 months, and 600 IU per day for older children and adolescents. To use another measurement, "most experts and scientists agree that a blood level of 40-60 ng/ml is the ideal range for vitamin D that can help reduce disease by up to 50 percent or more," says Dr. Gaither.
Babies who are fully or partially breastfed should get 400 IU from vitamin D supplements (in the form of drops) until they're fully weaned and drinking milk that's fortified with D, according to the Centers for Disease Control and Prevention (CDC). Breast milk does not contain sufficient vitamin D to meet babies' needs.
It's also important to note there's no evidence that getting megadoses of vitamin D has any health benefit. NIH says excessive levels may contribute to symptoms like weight loss, heart arrhythmias, and raised blood levels of calcium.
What Are the Best Sources of Vitamin D?
Unfortunately, few foods are naturally rich in vitamin D. A three-ounce serving of salmon contains all the vitamin D kids need in a day, but the same serving of canned tuna has less than half. Eggs contain a small amount of vitamin D (in the yolk) but kids would need to eat about 10 a day to meet their daily needs. Mushrooms naturally contain vitamin D and some are treated with UV light to boost the vitamin content (white button mushrooms and baby bellas are the kind most commonly treated, but check the Nutrition Facts Panel to see if there's extra D).
Fortified foods like milk, yogurt, cereal, and orange juice may seem like a more manageable way to help your child get his daily D. A cup of fortified cow's milk contains about 130 IU of vitamin D; a cup of fortified orange juice has 142 IU. Check the labels on the cereal and yogurt you buy to see if they're fortified.
Luckily, children can also get vitamin D through exposure to sunlight, because the sun converts a chemical in the skin to an active form of D. According to the AAP, even if kids wear sunscreen (which they should!), many will get enough sunlight in their day-to-day lives to produce enough D.
That being said, Dr. Gaither says children can safely get vitamin D through supplementation (including a basic multivitamin that contains D). Vitamin D supplements are readily available and inexpensive to buy. They may be especially necessary if you live in a cloudy climate, have long winters and aren't outside very much, or if you feel like your child's diet is lacking in D. Ask your pediatrician for more information.
Does My Child Have Vitamin D Deficiency?
Want to know your kid's vitamin D levels? You can ask your doctor to check them, but you can also get results in the comfort of your own home. "I'm a fan of testing vitamin D at home, especially now during the pandemic when we need to limit visits to the doctor that are not urgent," says Dr. Gaither. "Your vitamin D blood level needs to be between 40-60 ng/ml and the only way to know that is to test your levels. A simple finger-prick vitamin D test kit is an easy way to discover how much vitamin D supplementation you need."
Once you get results, you can use a free vitamin D calculator (like this one found at www.NutrientPower.org) to estimate how much is needed to reach your desired target level. You can increase your level by getting sunlight (while wearing sunscreen, of course), eating foods rich in vitamin D, or taking supplements if your doctor suggests them.
Dr. Gaither says it's recommended to retest vitamin D levels every six months.
Additional reporting by Nicole Harris.