Babies need vitamin D for healthy growth and development. It helps them build strong, healthy bones and teeth.

Babies who don’t get enough vitamin D are at risk of getting rickets, a disease that affects the way bones grow and develop. Vitamin D can also help prevent certain illnesses in childhood or later in life.

Fortunately, vitamin D deficiency (not having enough) can be prevented by giving a daily supplement (drops) to babies who are at risk.

How do I know if my baby is at risk of vitamin D deficiency?   
Vitamin D comes from different sources:   

• Foods: In Canada, cow’s milk and margarine are fortified with vitamin D, which means it’s added to them during production. Some foods-like salmon, tuna, liver and kidney-are good sources of vitamin D.
• Sunlight: Vitamin D is formed naturally when skin is exposed to sunlight. But because Canada is located so far north, sunlight isn’t enough at certain times of the year and in certain places. Sunscreen and clothing, which protect babies from the harmful effects of the sun, won’t allow vitamin D to be formed.  

Babies are most at risk of vitamin D deficiency if: 

• They are exclusively breastfed.
• Their mothers are vitamin D deficient.
• They are not exposed to enough sunlight.
• They have darker skin.
• They live in northern communities.

These babies should get a daily supplement of vitamin D. 

Babies in northern communities (north of 55° latitude, which is about the level of Edmonton) or who have other risk factors (such as dark skin) should get 800 IU per day between October and April, when there is less sunlight.

Why do breastfed babies need a vitamin D supplement?   
Breast milk is the best food you can offer your growing baby. For the first 6 months of life, it is all your baby needs. Even when your baby starts eating solid foods, you can continue to breastfeed until 2 years of age and beyond. 

Since breast milk is naturally and uniquely produced-by each mother for her own baby—your baby is less easily exposed to foreign allergenic material. Breast milk also contains antibodies and other immune factors that help prevent and fight off illness better. 

Breast milk has the right amount and quality of nutrients to suit your baby's first food needs. It is also the easiest on the digestive system, so there's less chance of constipation or diarrhea.

But breast milk, which has only small amounts of vitamin D (4 to 40 IU per litre), may not have enough to meet your baby’s needs. That’s why babies who are breastfed should receive a daily supplement of vitamin D from birth until they get enough from their diet.

Do babies who are formula-fed need extra vitamin D?  
Since vitamin D is already added to infant formula, most full-term babies who are formula-fed don’t need a supplement. However, formula-fed babies in northern communities should receive a supplement of 400 IU/day during from October to April to ensure they have enough vitamin D.

If I am breastfeeding and I eat foods rich in vitamin D, do I still need to give my baby a supplement?  
Yes. Although some foods are good sources of vitamin D, they won’t provide enough vitamin D to enrich your breast milk to the level your baby needs.

If you are breastfeeding, talk to your doctor about whether a supplement of 2000 IU/day is appropriate for you.

Should pregnant women take vitamin D supplements?  
If you don't get enough vitamin D while you're pregnant, that will affect how much vitamin D your baby has at birth. A baby born to a mother who is vitamin D deficient is more likely to have a vitamin D deficiency.

Milk and margarine produced in Canada are fortified with vitamin D. If you don't use these products, if you do not have much exposure to the sun or if your skin is covered much of the time, especially if you do not take vitamin D supplements, then you are more likely to be vitamin D deficient.

If you are pregnant, talk to your doctor about whether a supplement of 2000 IU/day is appropriate for you.

For more information: 

• Breastfeeding
• Vitamin D supplementation: Recommendations for Canadian mothers and infants, a statement of the Canadain Paediatric Society

Developed by the CPS First Nations, Inuit and Métis Health Committee 

Updated: September 2007