Supplements and vitamins for your baby

Nutritional Guide

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Baby getting supplements in syringe

Some babies do need additional supplementation of certain vitamins. For example, very premature infants – born weighing less than 3.3 pounds – will likely need extra vitamins and minerals added directly to breastmilk or formula. Additionally, babies who are exclusively as well as partially breastfed should be given vitamin D starting at birth, and an iron supplement starting at age 4-6 months.

The most common supplements recommended for babies include:

Vitamin K

The American Academy of Pediatrics recommends that all babies receive a one-time vitamin K injection shortly after birth to reduce the risk of hemorrhagic disease. Vitamin K is necessary for our bodies to activate certain molecules that help the blood to clot.

Vitamin D

Vitamin D allows the body to absorb and retain calcium and phosphorus, both critical for building strong bones. A vitamin D deficiency can lead to rickets, a bone-softening disease that still impacts children in the U.S., usually in the first two years of life.

Since breastmilk does not provide adequate vitamin D, all breastfed babies should receive a supplement. Formula fed babies generally do not need additional vitamin D supplementation because formula has vitamin D already added. If your baby is drinking at least 32 ounces of formula per day, she’s receiving adequate amounts of vitamin D.

Vitamin B12

Vitamin B12 keeps the body’s nerve and blood cells healthy and helps make DNA, the genetic material in all cells. Vitamin B12 deficiency can cause a type of anemia called megaloblastic anemia that makes people tired and weak.

Vitamin B12 is not present in plant foods, so breastfeeding moms who follow a strict vegan diet (meaning, they aren’t eating any animal foods) will need to supplement their diet with vitamin B12 to make sure that both they themselves and their babies are receiving adequate levels.

Signs and symptoms of vitamin B12 deficiency in infants include vomiting, lethargy, anemia, failure to thrive, hypotonia (low muscle tone), and developmental delay/regression. Breastfed infants can develop vitamin B12 deficiency by 2-6 months of age, but the symptoms may not become apparent until 6-12 months. And breastfed infants may develop clinical signs of vitamin B12 deficiency before their mothers do. For more information, see How can I ensure my baby and I are meeting our needs with a vegan diet?


Breastmilk is low in Iron but most babies are born with sufficient reserves of iron to protect them from anemia, at least until the age of 4-6 months. If you had poorly controlled gestational diabetes, or your baby was premature or smaller than 6 pounds at birth), your baby may not have gotten enough iron during pregnancy.

The AAP recommends exclusively and partially breastfed infants receive 1 mg/kg/day of a liquid iron supplement starting at 4-6 months and continuing until iron-containing solid foods are introduced at about six months of age. Speak with your baby’s doctor about Iron supplementation.

When you begin to introduce your baby to solid food, choose foods that contain iron, like fortified cereals, meats, fish, beans and vegetables (and see Nutritional requirements for 6-12 month olds for more on how to pack an iron punch).

What to Do


Your baby is receiving adequate iron and vitamin D in her formula so continue feeding bottles of formula through the first year of life.

If breastfeeding, the AAP recommends exclusively and partially breastfed infants should receive 1 mg/kg/day of a liquid iron supplement starting at 4-6 months and continuing until iron-containing solid foods are introduced at about six months of age. Starting at birth, 400 IU of supplemental vitamin D daily is recommended, continuing until about 1 year of age.

If your baby was born prematurely, she may need a higher iron supplementation of 2 mg/kg/day starting within the first month of life. Speak with your baby’s doctor about your baby’s specific needs.

If you are vegan or vegetarian, take a B12 supplement and talk with your healthcare provider and a Happy Family Milk Mentor coach to make sure your own diet and supplements are adequate for your baby and for you.

Talk to your healthcare provider about options for vitamin D supplements

You have several options for delivery of vitamin D supplements, from drops that are placed straight on your nipple while nursing or into your baby’s bottle to less concentrated dosages fed directly to your baby through a dropper or syringe.

Your healthcare provider will help you determine the best method and dosage for your baby’s size and age.

Do not introduce cow’s milk until after your baby’s first birthday

Babies who are fed cow’s milk (instead of breastmilk or iron-fortified formula) during the first year of life are more likely to develop iron-deficient anemia because the excessive amount of protein in cow’s milk can also overload a baby’s kidneys.

After 6 months of age, introduce iron-rich foods like green vegetables, meats and cereals

After 4-6 months, your baby’s natural iron stores from birth will begin to decrease. Do not be afraid to feed your baby the proteins and leafy greens that will give her all the nutrients she needs. After all, our bodies process iron in a more natural way when it comes from the foods we eat as opposed to supplements or vitamins.

Some iron-rich foods include: Soybeans, lentils, spinach, garbanzo beans, navy beans, swiss chard, kidney beans, tofu, black beans, beef, and eggs.

Brush with fluoride toothpaste and talk to your pediatric dentist or physician about fluoride supplements

As soon as you see teeth coming in, begin brushing your baby’s teeth with a small rice-sized amount of fluoride toothpaste twice per day. For more information on fluoride usage in drinking water and requirements for your baby, see What are the fluoride recommendations for my baby?