Improving your baby’s bone health starts in the womb

For February, we’re focusing on the body parts that shape us, oxygenate us, and power us as we take long walks on the beach. Bony bonafide bones. These skeletal building blocks inspire curiosity and spark fear in different folks—we hope our stories, covering everything from surgeries and supplements to good old-fashioned boning, will only do the first. Once you’ve thoroughly blasted your mind with bone facts, check out our previous themed months: muscle and fat.

As new parents there are a lot of things to learn (and worry) about. A big one is your baby’s bones. The steps you take to ensure your baby gets good nutrition from their time in utero up to their first birthday can have a lasting impact on how they grows. They can even play an important role in preventing future fractures and medical conditions like osteoporosis.

Maintaining bone health is a little like having a savings account, says Dr. Jen Trachtenberg, an assistant clinical professor of pediatrics at The Icahn School of Medicine at Mount Sinai. She says helping your child get good nutrition is like making a deposit to help prepare for future withdrawals.

“A diet rich in calcium and other minerals keeps withdrawals, or bone loss, to a minimum,” she explains, noting that children with the highest peak bone mass after adolescence have the greatest advantage in terms of future bone health.

In utero: Mom’s calcium and vitamin D intake is key

The first steps to healthy bones for babies begin before birth, during pregnancy.

“A mom’s nutrition, her calcium intake and vitamin D levels, are all very important to assure that the baby has healthy bones,” says Dr. Monica Grover, assistant professor and co-director of the Bone Health Care program at Stanford University’s Lucile Packard Children’s Hospital.

While the average prenatal vitamin contains 400 international units (IU) of vitamin D, a recent study cited by the American Pregnancy Association recommends pregnant women take 4,000 IU of vitamin D daily. So, the APA suggests taking supplements to make up the difference. But recommendations may differ—the American College of Gynecologists sets a lower minimum threshold for vitamin D at only 600 IU per day.

For calcium intake, the ACG recommends all adult women over 19, pregnant or not, get 1,000 milligrams of calcium each day. The recommendation is a little higher for teenagers, who should get 1,300 milligrams of calcium on a daily basis, whether they’re expecting mothers or not.

At birth: Make sure baby gains weight

Once a baby is born, the most important thing you can do for their teeth and bones is ensure they are feeding well and gaining appropriate weight. Just as it is for mothers during pregnancy, the key nutrient to track at this stage is your little one’s vitamin D intake, which, along with calcium, will ensure a healthy development of their bone structure.

Babies need a minimum of 400 IU of vitamin D per day, beginning at birth and up until their first birthday. Those who exclusively feed on fortified formula will get enough vitamin D as long as they get 32 ounces (about 1 liter) per day. On the other hand, babies who exclusively feed on breast milk or receive less than 32 ounces of fortified formula daily will need 400 IU of vitamin D supplements per day, as this nutrient is not as easily absorbed or readily available in breast milk, explains Trachtenberg, who is also a spokesperson for the American Academy of Pediatrics.

This is necessary even if the nursing mom is taking vitamin D supplements while breastfeeding. To be able to transfer this nutrient to a child through breast milk, mothers would have to consume between 4,000 and 6,000 IU daily, which, according to Grover, is not common.

The key with formula is to ensure it is fortified and mix it as directed (with the right amount of powdered formula and water) so your baby gets the correct levels of nutrients, Trachtenberg says

Infancy and beyond: Transition to solid foods and whole milk

The American Academy of Pediatrics recommends exclusive breastfeeding for the first six months of your child’s life, and after that, you can introduce solid foods into their diet. By age 12 months, the AAP says your baby should be consuming about 1,000 calories per day over three meals and two snacks.

To support healthy bones, Trachtenberg recommends incorporating foods rich in vitamin D and calcium, such as yogurt, cheese, salmon, eggs, beans, and green vegetables.

Keep in mind that introducing new food to a child might be a long and difficult task. Trachtenberg says it may take between 10 to 15 attempts before babies are ready for them, but there are some things you can do to make things easier both for them and for you:

• Be persistent and consistent
• Try different ways of preparing the foods (such as baked, pureed, or sauteed)
• Never force your child to eat something
• Remember it will take time for your child to form new habits

After their first birthday, babies can transition to whole milk—a good source of vitamin D and calcium. At this age, the recommended daily intake of vitamin D also increases to 600 IU, Trachtenberg says. According to the AAP, toddlers should consume about two to three servings of dairy per day, be that half a cup of milk, a 1-inch cheese cube, or a third of a cup of yogurt.

If your child doesn’t like whole milk, or dairy in general, Trachtenberg says they can also get these nutrients from non-dairy sources. However, Grover is cautious and says it’s more challenging to get these nutrients from a solely plant-based diet.

“You have to eat a lot of broccoli and a lot of spinach to get the same amount of calcium that you can get from dairy products,” she says, adding that if your child is eating only vegetables, they will likely need supplements. Multivitamins containing vitamin D and calcium can be a good idea, offering 300 to 600 IU of vitamin D and 100 to 250 milligrams of calcium per serving.

While there are some factors about bone development and health you can’t control—like chronic illnesses and genetics—the habits parents build during the first period of their babies lives can help children establish a foundation for good health that lasts all the way to adulthood.