Vitamin D

By Angela Wilson
Certified child sleep consultant, MA Natural Sciences Cambridge University and co-founder of Baby Smiles Club 

Both you and your baby need vitamin D. The best source of vitamin D for adults is sunlight. When our skin is exposed to sunlight, the ultraviolet B (UVB) rays interact with a protein called 7-DHC in the skin, converting it into vitamin D3, which is the active form of vitamin D.

Babies have very sensitive skin, which means they shouldn’t be exposed to direct sunlight. This makes it hard for them to make vitamin D from the sun – and so they either need to get it from a supplement or from their formula (depending on whether they’re breastfed, formula fed or combination fed). 

Why does a baby need vitamin D? 

Babies need vitamin D for healthy growth and development. It helps them build healthy bones and teeth, and strengthens their immune system. And if vitamin D levels are low, a baby has a risk of developing rickets, a condition that causes weak or deformed bones. 

What’s the best way for a baby to get vitamin D? 

Both the American Academy of Pediatrics and the NHS in the UK (together with other relevant institutions worldwide) recommend that breastfed babies be given a daily vitamin D supplement from birth. 

Babies who are formula fed and taking over 1 litre of formula a day don’t need to have a vitamin D supplement, because formula is fortified with vitamin D (and other nutrients). If a baby is having less formula than this, or is combination fed, they may need vitamin D supplementation. The recommended daily amount of vitamin D is 400 IU; you can work out how much they are getting from the formula ingredient list, and how much supplementation they might need. 

You should talk to your medical advisor if you’re using formula and want to be sure your baby is getting enough vitamin D.  

You can find vitamin D supplements easily in shops or online. Please feel free to ask us if you’d like to know a good brand to get! 

Our Baby Sleep Program is a holistic program to help your baby sleep well from birth right up to a year old. It's a modern, gentle and caring approach to baby sleep, based on the most up-to-date science about how babies sleep, and fostering and strengthening the parent-baby bond. 

Find out more about our Baby Sleep Program