Should I give my breastfed baby vitamin D drops? Are vitamin D drops necessary for babies?
Breastmilk is tailor made to fit your baby and provides all the energy, nutrition and hydration your baby needs for at least the first 6 months of life. It has just one caveat... it doesn't contain much vitamin D!
But why would the milk we tailor-made for our babies not contain everything they need? Well, breast milk was never supposed to supply our babies with vitamin D, we were supposed to get vitamin D from the sun. But we are now aware of the long term damage from sun exposure and as a result the current safe sun advice in the UK is that babies shouldn't be exposed to the sun for prolonged periods of time during the early months, therefore we have cut off the production of this vital vitamin at its source!
If I am supplementing vitamin D myself and breastfeeding my baby, should I give my baby vitamin D?
If you are taking the current recommended amount of vitamin D - 400 IU or 10 micrograms - this is not enough to pass into breastmilk at a high enough level to keep your baby from getting vitamin D deficiency. This is why the UK currently recommends babies take an additional 400 IU / 10 micrograms vitamin D per day to prevent vitamin D deficiency.
Are there any other options?
You may decide you do not want to supplement your baby and be wondering if there are any alternatives. It is not possible to say what if any sun exposure if safe for babies, but it would be wise to avoid peak midday and afternoon sun- when UV rays are at their strongest. It is also not possible to say how much sun exposure would provide sufficient vitamin D levels in babies either, this is not something we have enough information on
What about high dose vitamin D supplements for mums?
Some studies have shown that maternal supplementation with higher amounts of vitamin D (higher than the current UK recommendation of 400 IU / 10 micrograms daily) can supply breastmilk with adequate vitamin D to transfer optimal vitamin D status to the nursing infant without the need for additional supplementation by the infant themselves (2)
The evidence:
In one randomised, double-blinded study, the vitamin D status of 216 exclusively breastfed babies taking standard dose vitamin D (400 IU/day), was compared with babies not taking any vitamin D, but whose mothers were taking a high dose supplement of 6400 IU vitamin D daily. They achieved adequate vitamin D levels in both sets of babies (2).
This shows that if maternal vitamin D status is improved via high dose supplement, breastmilk can transfer sufficient vitamin D without the need for additional supplementation in the nursing infant.
One caveat is that the NHS warns of risks of high dose vitamin D supplementation over long periods of time largely due to concerns regarding a potential build-up of calcium in the body which can damage bones. As a result, they currently advise adults and children not to take more than 100 micrograms (4000 IU) of supplemental vitamin D daily. However, the above study of short-term high-dose vitamin D during lactation (2) reported no vitamin D toxicity or adverse events related to vitamin D supplementation, including no episodes of hypercalciuria in the mums. Circulating vitamin D levels in the mums in the study were actually consistent with those in populations with natural solar exposure and no additional vitamin D supplements!
Can I get vitamin D from food to avoid supplementation?
There are very few naturally rich food sources of vitamin D, and those that do contain do not really contain enough (sources include: eggs, oily fish, some wild mushrooms) and so it can be quite challenging, if not impossible, to get enough vitamin D from food alone (3). Our bodies are designed to make vitamin D via exposure to sunlight and not to get it from food. But getting enough from the sun has become harder due to changes in our lifestyles, spending more time inside and covering up or wearing high SPF when we do venture outside. This has meant that more and more of us are becoming vitamin D deficient.
What does vitamin D do? Can low vitamin D affect my baby?
Vitamin D helps our bodies to absorb calcium, plays a role in bone metabolism, supports our immune system, and more recently low vitamin D levels have been linked to cancer and diabetes (4,5). Because vitamin D is essential for calcium absorption and bone metabolism, in a small number of cases of babies and young children with vitamin D deficiency it can progress to rickets. Rickets is a condition that affects bone development causing growing bones to become weak and can cause bone deformities.
What is the risk of vitamin D deficiency rickets in infants and children?
A study in 2020 reported on the incidence of rickets in children in the UK: reporting 0.48 cases per 100,000 children under 16 years (5). Of the 125 babies and children who met the criteria for vitamin D deficiency rickets (serum 25-OH vitamin D levels <25nmol/L) they noted the following:
Children aged 12-23 months were most affected
77.6% were not taking vitamin D supplements
Exclusive breastfeeding and not taking vitamin D supplements was a significant risk factor
Twelve babies presented under the age of 6 months and were not receiving vitamin D supplements developed rickets
Surprisingly one infant was exclusively formula-fed
Complications included delayed gross motor development (26.4%), fractures (9.6%), hypocalcaemic seizures (8%) and dilated cardiomyopathy (3%)
Additional risk factors: boys (70%) were significantly more affected than girls (30%), the majority were of Black (43%) or South Asian (38%) ethnicity
Presence of cow’s milk allergy/intolerance was also associated with development of vitamin D deficiency rickets highlighting the importance of calcium and vitamin D intake in at risk groups (6)
Vitamin D deficiency and exclusive breastfeeding, what does the science say?
Cases of rickets in children and infants are rare, but the above study showed that exclusive breastfeeding and not taking vitamin D supplements was a small but significant risk factor. Another study, looked at 2500 healthy infants, and found that each 1 month increase in breastfeeding duration was associated with a drop in serum 25-OHD (vitamin D) of 0.12 ng/mL in those who were not supplemented (7)
What happens if I haven’t been giving my baby vitamin D drops?
Don’t panic if you haven’t given your baby vitamin D drops, it is unlikely to cause any harm, as the risks of rickets are just less than 2 in 200,000. But it is recommended to give all babies and young children up to the age of 4 vitamin D drops daily all year round to prevent deficiency so you can choose to do this for the remainder of this time (adults and older children can take these during the winter months too to top up vitamin D stores!) (9)
What are the current UK recommendations for vitamin D supplementation?
“Babies from birth to 1 year of age who are being breastfed should be given a daily supplement containing 8.5 to 10 micrograms of vitamin D”. This is irrespective of a mother taking vitamin D supplements (8)
Babies fed infant formula should not be given a vitamin D supplement if they're having more than 500ml (about a pint) of infant formula a day, because infant formula is fortified with vitamin D”
Children over one year of age should be given a daily supplement containing 10 micrograms of vitamin D
Adults, including pregnant and breastfeeding women, should take a supplement of 10 micrograms of vitamin D a day (9)
How do I know if my baby is vitamin D deficient?
The way to check for vitamin D deficiency is via a blood test. Here are the current thresholds for vitamin D levels in the UK:
Deficiency: less than 25 nmol/L
Inadequate (or insufficient): 25–50 nmol/L
Sufficient: greater than 50 nmol/L (10)
References:
1. WHO https://www.who.int/health-topics/breastfeeding#tab=tab_1
2. Hollis BW, Wagner CL, Howard CR, Ebeling M, Shary JR, Smith PG, Taylor SN, Morella K, Lawrence RA, Hulsey TC. Maternal Versus Infant Vitamin D Supplementation During Lactation: A Randomized Controlled Trial. Pediatrics. 2015 Oct;136(4):625-34
4. Feldman D., Krishnan A.V., Swami S., Giovannucci E., Feldman B.J. The role of vitamin D in reducing cancer risk and progression. Nat. Rev. Cancer. 2014;14:342–357. doi: 10.1038/nrc3691
5. Zakhary CM, Rushdi H, Hamdan JA, Youssef KN, Khan A, Abdalla MA, Khan S. Protective Role of Vitamin D Therapy in Diabetes Mellitus Type II. Cureus. 2021 Aug 20;13(8):e17317.
6. Julies P, Lynn RM, Pall K, et al Nutritional rickets under 16 years: UK surveillance resultsArchives of Disease in Childhood 2020;105:587-592.
7. Denise Darmawikarta, Yang Chen, Gerald Lebovic, Catherine S. Birken, Patricia C. Parkin, and Jonathon L. Maguire, 2016: Total Duration of Breastfeeding, Vitamin D Supplementation, and Serum Levels of 25-Hydroxyvitamin D. American Journal of Public Health 106, 714_71
8. NHS https://www.nhs.uk/conditions/baby/weaning-and-feeding/vitamins-for-children/
9. NHS https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
7. NICE https://cks.nice.org.uk/topics/vitamin-d-deficiency-in-adults/