What do systematic reviews say?

Vitamin D given to infants vs vitamin D given to lactating mothers

It is very uncertain whether vitamin D given to infants changes vitamin D insufficiency: 25‐OH vitamin D < 50 nmol/L compared with vitamin D given to lactating mothers (very low certainty).

• Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes only
  RR 0.61 [0.4, 0.94]
  4 studies · 334 participants
  Very low

Vitamin D given to infants vs vitamin D given to lactating mothers

It is very uncertain whether vitamin D given to infants changes vitamin D deficiency: 25‐OH vitamin D < 30 nmol/L compared with vitamin D given to lactating mothers (very low certainty).

• Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes only
  RR 0.35 [0.17, 0.72]
  4 studies · 334 participants
  Very low

Vitamin D given to infants vs vitamin D given to lactating mothers

• Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes only
  no estimate extracted
  4 studies · 269 participants
  Low

Vitamin D given to infants vs vitamin D given to lactating mothers

• Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 92 participants
  Very low

Vitamin D given to infants vs vitamin D given to lactating mothers

Vitamin D given to infants showed no clear difference in adverse effect (hypercalcaemia) compared with vitamin D given to lactating mothers (low certainty).

• Vitamin D supplementation for term breastfed infants to prevent vitamin D deficiency and improve bone health 2020 · Cochrane Headline outcomes only
  RR 1.22 [0.48, 3.09]
  1 study · 97 participants
  Low