Safety in Lactation: Vitamins

Vitamins are normally divided into two groups – fat soluble (vitamins A, D, E and K) and water soluble (vitamins B and C).
Maternal vitamin supplements pose no risk to breastfed infants when taken in normal doses, although their use should be unnecessary unless the mother’s nutritional status indicates a vitamin deficiency. Excessive doses should be avoided.
Although most vitamins can be given to neonates for deficiency-related conditions, their routine use in neonates is normally unnecessary. Vitamins D and K are the two exceptions.
In the UK a daily 10 microgram vitamin D supplement is recommended for pregnant and breastfeeding women. Low sunlight exposure or maternal dark skin presents a higher deficiency risk.
The use of high dose or prolonged use of vitamin D and its analogues in mothers must be approached with caution due to potential to cause neonatal hypercalcaemia. Monitoring infant calcium levels is advised in these situations.
Vitamin K which should be given to all neonates at birth to prevent haemorrhagic disease due to relative neonatal deficiency and naturally low breast milk levels.