Does My Infant Need a Multivitamin?

Guest Post by Christina Anderson MS, RDN, CDE, CNSC, LD@Pediatric.Nutritionist

Christina Anderson MS, RDN, CDE, CNSC, LD is a pediatric registered dietitian who has worked in a variety of settings, including the NICU, pediatric hospital inpatient, and pediatric outpatient clinics (gastroenterology and endocrinology). She has a private practice and also sees clients virtually from the convenience of their homes. She completed her dietetic internship at Duke and went on to complete her MS in Nutrition at the University of Oklahoma Health Sciences Center with research in type 1 diabetes and young adults. She is passionate about child feeding and troubleshooting feeding and growth issues, having worked very closely with feeding therapists that specialize in infants. Practicing with evidence-based medicine is her M.O. and she enjoys helping new parents sort through all the “noise” that their families, friends, and social media accounts provide. She recently moved from Oklahoma to Cheyenne, WY with her Air Force husband and their chocolate lab, Cooper.  In her free time, she loves reading the latest research, playing Julia Child in the kitchen, and hiking (when it’s not freezing!). 

Does your infant need a multivitamin? 

As a pediatric registered dietitian nutritionist, I’ve seen and heard all sorts of advice related to babies and multivitamins. Unfortunately, not all of it is true, and it is essential we feed our children the proper nutrients to help them grow and develop. We know that certain nutrients like iron, vitamin D, choline, calcium, and more are crucial to proper development and have a BIG impact down the road. 

Some parents feel like every child needs a multivitamin as “nutrition insurance” while others feel like the breast milk or formula their child is consuming should “naturally” provide everything they need to grow and thrive. 

The truth is, every infant is different! 

The American Academy of Pediatrics has answered this age-old question through a variety of studies and position papers. See here and here

Vitamin D and Iron are the main nutrients we need to think about for infants. There are a lot of myths out there about what is needed and when. 

To start, Vitamin D is an essential fat-soluble vitamin that all babies need mainly for bone health. Some pediatricians tell breastfeeding moms that taking a vitamin D supplement is sufficient to provide enough vitamin D in the breast milk. This is untrue. An infant needs 400 IU (international units) of vitamin D per day, and 1 liter (~32 oz) only contains 25 IU of vitamin D (cite). 

Exclusively breast fed babies should be supplemented with 400 IU daily of vitamin D, starting within the first few days of life. If your infant is taking less than 32 oz of formula per day or combination breast/formula fed, they also need 200-400 IU of vitamin D per day. 

Vitamin D drops can be purchased over the counter, recognized by the name “Enfamil D-Vi-Sol”, Carlson Baby’s Super Daily D 400 IU, Zarbee’s Naturals Baby Vitamin D Supplement, etc. Some are 400 IU per drop, others are 400 IU per 1 mL, and others are 0.25 mL per 400 IU, so it is important to read the serving size on the label. Like anything in life, too much can be toxic so you only want to give what is needed. More is not better in this case. 

Vitamin D is generally given once per day, and can be mixed into a bottle but you need to ensure they finish the entire bottle. Force feeding is never a good idea, so it may be better to gently syringe the vitamin D in small amounts via the side of their mouth than try to make them finish the bottle that has the supplement. 

Beyond vitamin D, iron is another an essential mineral for brain growth and development.

For the exclusively breastfed (EBF) infant, an iron supplement should be given at about 4 weeks of life until 6 months of age when they start iron-rich solid foods, and continued until 12 months as needed based on dietary diversity. Breast milk contains very little iron, and iron is needed at 1 mg per kg per day (equivalent to about 0.5 mg per pound) for the first 6 months of life. Babies develop at different rates, so some at 9 months are still relying on a larger portion of breastmilk or formula as they are still progressing with solids. With the upsurge in baby led weaning (BLW), which may not use as iron-rich foods at first, it’s important to incorporate iron-rich foods as able. See here for more details. Whichever way you choose (puree vs BLW vs combo feeding) to start solids, you should aim for using iron-rich food sources like beef, more ideas listed here

For the EBF infant born at a low birth weight (less than 5 lbs 8 oz or 2500 g), as a multiple (twin or triplet), or to a mom with diabetes, they may have lower iron stores at birth and may need more than the 1 mg per kg per day dose for the first few months. As always, you should follow your pediatrician’s guidance as to when a supplement is needed. They should routinely check blood labs that are related to iron stores (hemoglobin, hematocrit), usually as a heel stick. Sometimes blood labs are also drawn from the vein for a more in-depth set of labs called a CBC (complete blood count) which can further delineate iron and mineral issues. 

For the average, healthy infant that is consuming at least ~32 oz per day (~1liter) of at least a 20 kcal per oz formula (mixing instructions found on can) they will meet their daily iron requirement. The RDA (Recommended Dietary Allowance) for iron after 7 months is 11 mg per day. As such, most infant formulas contain 10-12 mg of iron per liter. If your formula is “concentrated”, i.e. you received a recipe for 24 calories per oz or 27 calories per oz, your infant will receive a lot more iron and this should be kept in mind when discussing further supplementation. 

If your infant is breastfed and supplemented with formula, you may need half a serving of an iron supplement per day, so 5 mg instead of 10 mg. Like the vitamin D supplement, you need to read the label and check the serving size of milligram (mg) iron per milliliter (mL). Healthcare providers calculate the dose of iron in “mg per kg” which is milligram per kilogram of bodyweight (2.2 pounds per kilogram). This can be confusing, so always check with your pediatrician because too much iron can be toxic.  

For infants born prematurely, they will need an iron supplement while in the NICU as they’ve missed out on the majority of maternal iron transfer that occurs last trimester. Iron will likely be given in the NICU as ferrous sulfate or a multivitamin with iron (like Poly-Vi-Sol + Fe which also has vitamin D) usually after 4 weeks of life. Some infants will need to be sent home on iron as “anemia of prematurity” can occur, and the pediatrician will continue to monitor iron status labs (hemoglobin and hematocrit). 

For infants diagnosed with iron deficiency anemia, your provider will typically supplement with 3-6 milligram per kilogram per day, but again you should keep in mind how much formula, breast milk, etc. they are receiving to truly calculate the appropriate dose. This is where brining in feeding records to your pediatrician visit can be really helpful! 

To help your infant take their iron, try the following:

If breastfeeding, you can gently syringe the iron drops into the side of their mouth in small amounts, then offer them the breast or bottle to help clear the harsh taste from their mouth. Do this slowly and gradually, you never want to force feed. 

For those struggling to feed, you don’t want them to start associating their main method of feeding (the bottle) with something negative. Some infants have no problem drinking the breastmilk or formula mixed with a supplement, but if it is not going well, don’t force the issue. Try to not mix into the bottle so they won’t associate the formula/breast milk with the harsh iron taste. 

For some babies, the iron supplement can cause digestive upset, i.e. constipation. If they are on formula, you may consider switching to a formula like Enfamil Reguline which has added prebiotics and is very helpful for constipation (not sponsored, just one of my clinical favorites from experience).  If over 4-6 months of age you can also try 1-2 oz of prune puree (stage I-II consistency based on their development) or 1 oz of high sugar fruit juice (white grape, prune, pear nectar) given once daily. The high sugar (naturally occurring) in these juices or nectars causes water to be drawn into the gut and help with constipation. Consult with your doctor if you are unsure about these remedies. As always, honey should not be given before 1 year due to a bacterium called Clostridium botulinum which causes botulism toxicity.

For more, visit: @Pediatric.Nutritionist

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