Signs of Vitamin D Deficiency in Babies

Your prenatal vitamins seemed to contain a whole alphabet of nutrients to ensure your baby develops well in your womb. But what happens after you meet your little bundle of joy in person? What nutrients does she need when she’s a growing baby out in the world?

Vitamin D is one of the most important nutrients your baby should be ingesting, but it’s also one of the trickiest ones for babies to get during the first six months after birth. Without it, babies may have a hard time developing strong bones and teeth and sustaining the health of other parts of their physiology, which we’ll go into more below.

What is vitamin D?

Vitamin D is a fat-soluble vitamin that is present in the foods we eat. While not naturally occuring in food it is fortified in many foods. Fat-soluble means that this vitamin is stored in the body’s fat for long-term use. While vitamin D can be absorbed in the foods that we eat, the best source of vitamin D is produced naturally with the help of two important ingredients:

• 7-dehydrocholesterol, a kind of cholesterol the body stores in the skin
• Sunlight exposure

When ultraviolet light from the sun meets the skin, the energy from that light converts 7-dyhydrocholesterol into vitamin D. To maintain healthy vitamin D levels using just sunlight, adults only need 10-30 minutes in direct sun without sunscreen a few times a week (a lunchtime walk will do it!). Depending on geographic location the duration may vary. Because of this, adults who spend enough time in the sun typically don’t have to worry about getting enough vitamin D in their diets—their bodies do the vitamin D work for them!

For babies, things get a little more complicated.

Why is your baby at risk for vitamin D deficiency?

Does everything you eat go to your baby? In short, yes! During pregnancy, a baby gets all the vitamins he needs from Mom, which is a good thing because scientists haven’t figured out a way to put a skylight in a pregnant mom’s belly (…yet.). So babies spend those nine months enjoying the warm, comforting dark of the womb while still getting enough vitamin D…until they’re born, or as it’s said in many romance languages, brought to the light (how beautiful is that?).

After they’re born, babies face a risk for vitamin D level deficiencies for a few reasons:

• Babies aren’t ready to be out in the sunlight (yet). It might be tempting to plop your newborn on a lawn chair and let him soak up those vitamin-D-producing rays (plus, how cute would that be?). But your child still has a lot of growing to do before he’s ready for direct sunlight. His baby skin is incredibly sensitive to sun damage for the first six months of life because melanin, a cell that protects your baby’s skin from excessive harm from the sun, hasn’t been developed yet. Melanin production is only triggered by sunlight, so it only begins after your baby’s birth. In the first six months, indirect light exposure will gradually increase your baby’s melanin so that after six months of age, he can be outside in the sunshine with the protection he needs
• There isn’t enough vitamin D in breast milk. In fact, the US National Institutes of Health reported that 81% of women of childbearing age have insufficient levels of vitamin D. If breastfeeding mothers doesn’t have enough vitamin D for her health, they may not have enough to ensure her baby is getting enough Vitamin D intake for his health.
• Infant formula has higher amounts of vitamin D than breast milk, but it isn’t always a sure bet. According to the CDC, 32 ounces of infant formula can provide the right amount of formula your baby needs. But how much of that formula is your baby actually getting? Between spit-ups, messy slurps, spills, and fussy spells (your baby’s not yours!), it can be difficult to ensure your baby is ingesting enough formula to ensure proper vitamin D levels.

Why is vitamin D so important for babies?

Why does your baby need vitamin D in the first place? Vitamin D supports several of the most important parts of your baby’s growth.

• Bone development – Vitamin D helps your child build healthy bones by ensuring proper calcium absorption in the body. Calcium is one of the most important elements in bone development, and it is vital to your child at this stage because babies grow a lot. Babies have an extraordinary growth rate, gaining about an inch of length every month, so it’s important to have enough calcium to power this growth. Normal vitamin D levels enable your baby to absorb up to 40% of the calcium he ingests. When you have low vitamin D levels, that absorption rate goes down to 10-15%.
• Making little teeth – It will be a while before your baby is taking his first bite of solid food, but his body will work on developing teeth long before it’s nibbling time. Much like bones, calcium is a key ingredient to healthy teeth. And, as we mentioned, the more normal those vitamin D levels are, the more calcium your child’s body can use to make his first chompers.
• Heart health – Scientists are still finding connections between healthy vitamin D levels and the health of other parts of a child’s body like the vascular system, heart, brain, stomach, muscle systems, and endocrine glands.

Does your baby need plenty of vitamin D? D stands for definitely. What can happen if he doesn’t get this important nutrient?

Side Effects of Vitamin D Deficiency

When it comes to a lack of vitamin D for babies, side effects in the long term include:

• Rickets: A disease that causes softness and weakness in bones. It can occur after prolonged vitamin D deficiency.
• Seizures: Due to low calcium levels for proper brain function.
• Heart issues: Since vitamin D has been linked to muscle strength. Because the heart is a muscle, a baby’s heart can weaken if there isn’t enough vitamin D to support the vascular system.

Thankfully, there are plenty of ways to spot low vitamin D levels before your child comes anywhere near these side effects.

Signs of Vitamin D Deficiency in Babies

Vitamin D deficiency is extremely treatable, and it can be helpful to know the signs and ensure your baby is on track for all of her vitamin needs.

Vitamin D deficiency in babies symptoms include:

#1 Slow Growth Rate

Vitamin D is required for proper bone and muscle growth. Since babies are little growing machines, lack of growth is a definite sign to give your child’s healthcare provider a call.

#2 Crankiness or Lethargy

Lack of vitamin D can cause muscle cramping and bone pain in a little one. If a child loses her playful attitudes and alertness and seems especially irritable without any known cause, it might mean something more is going on with her body.

#3 Tetany

Tetany is a condition in which there isn’t enough calcium in a baby’s bloodstream. Remember, vitamin D helps ensure that your baby is absorbing plenty of calcium. When your child runs low on vitamin D, that also means she’s running low on calcium. Tetany can cause apneic spells—or episodes where it seems like your child is having a hard time breathing—wheezing, muscular weakness, and, in the worst cases, seizures.

How To Ensure Your Child Gets Enough Vitamin D

A vitamin D deficiency can seem daunting, but the good news is there are several simple ways you can ensure your baby is getting everything he needs to grow up healthy and happy with all the vitamin D his body requires.

Supplement Both Formula and Breast Milk with Vitamin D Supplements

When it comes to child multivitamins, the first thing that might come to mind are those Flintstones vitamins you may have eaten as a kid. But babies have a ways to go before they start enjoying chewable, fruity, or cartoony vitamins. Instead, pediatricians recommend vitamin D supplementation by adding 400 international units (UI) of vitamin D in the form of vitamin drops to your baby’s diet once a day soon after birth.

The American Academy of Pediatrics definitely recommends 400iu daily of vitamin D for infants who are breastfed, however, if a baby is being formula fed, many times there already is 400iu in this. So mosts formula fed babies don’t need the additional supplementation. Check with your formula’s ingredients list to ensure your baby is getting enough vitamin D.

• If you’re breastfeeding, continue with this dosage until your breastfed infant is weaned or until he can drink 32 ounces a day of vitamin D-fortified formula or, after he reaches 12 months, whole cow’s milk.
• If you’re using formula, keep giving your baby vitamin D supplements until he can drink a minimum 32 ounces of formula every day.

As your baby gets older and graduates from breastmilk or formula, you can also make sure that you are introducing the best first baby foods to help your little one maintain proper vitamin levels!

Spend a Little Time in the Sunshine

The easiest and cheapest way to give your baby a dose of vitamin D? Get some sun exposure! Keep in mind, a dose of sunshine is only recommended once a child has reached 6 months of age, when melanin production has had a chance to help protect your child’s skin from UV rays. If you want to celebrate your baby’s six-month birthday with a picnic, be sure to keep him protected with:

• A baby hat with a wide brim to protect that cute face
• Long-sleeved clothing to keep him covered
• Baby sunscreen to ensure maximum sun protection

Recognizing the signs of Vitamin D deficiency in babies, such as slowed growth rate and increased irritability, can prevent potential long-term issues such as rickets and heart problems. Ensuring your infant has enough Vitamin D through supplementation or careful sun exposure after six months of age, can foster optimal growth and health during this critical period of rapid development.

This post has been reviewed for accuracy by the following medical professional:

Dr. Heather Soper, Certified Nurse Midwife

Dr. Heather Soper brings over 15 years of experience in women's health and obstetrics to her role as the owner of The Genesis Resort for Birth. Complementing her clinical practice, she serves as an Assistant Professor of Nursing at James Madison University, where she educates nursing students with a focus on compassionate, patient-centered care. Her advanced training and dedication to midwifery are evident in her contribution to both academia and the wellness of expectant mothers

Sources:

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