Preterm infants lack B vitamins from breast milk

Breast milk is packed with nutrients that are naturally designed to support a newborn’s growth and development. It is therefore recommended that newborns receive only breast milk during their first six months. However, preterm infants with low birth weight who are exclusively breastfed without additional multivitamin supplementation do not get enough B vitamins. According to a Norwegian study published in Nutrients, this can have a number of health consequences, especially ones that involve the central nervous system. The authors therefore recommend that mothers of preterm infants with low birth weight receive specific dietary guidance in order to optimize their children’s vitamin and mineral status.

From the moment a child is born, rapid growth and development continue. As a result, infants still have a relatively high requirement for nutrients, particularly in relation to the central nervous system.
An infant’s micronutrient status depends on gestational age and birth weight, as well as the mother’s nutrient status during pregnancy and the nutrient content of breast milk after birth when the infant is exclusively breastfed.
Breast milk is unique because it contains all the nutrients a newborn needs for rapid growth and development, including support for the immune system, digestion, and nervous system. However, because preterm infants with low birth weight can only consume limited amounts of milk, they may not obtain sufficient nutrients through breastfeeding alone.
In addition, breast milk is often low in vitamin K1 and vitamin D. There have also been concerns about deficiencies of various B vitamins, which are particularly important for infant growth and development, including DNA methylation and the central nervous system.

Multivitamins with B vitamins should be improved for preterm infants

The concentration of most B vitamins in breast milk, except folate (B9), is normally high during the first 2-4 months of lactation. However, evidence suggests that preterm infants with low birth weight do not get enough B vitamins if they are only breastfed. The new study examined this issue from birth through the first year of life.
The study included 64 infants from Haukeland University Hospital in Bergen who were born prematurely and with low birth weight (under 1,500 grams). All infants were exclusively breastfed during the first six months, and some of them also received special multivitamins designed for preterm infants.
During hospitalization, the researchers examined various parameters related to the infants’ growth and nutritional status. Blood samples were also collected. The mothers and infants were then invited for follow-up visits after 2, 6, and 12 months.
The researchers examined the infants’ levels of vitamin B12 (cobalamin), vitamin B9 (folate), the active form of vitamin B6 (pyridoxal 5'-phosphate, PLP), and vitamin B2 (riboflavin). They also measured markers such as homocysteine, which are normally broken down by B vitamins, as well as methylmalonic acid (MMA), where elevated levels indicate vitamin B12 deficiency.
The study revealed that the group of infants receiving multivitamin supplements had higher levels of active vitamin B6 (PLP) and vitamin B2.
The group of infants who received breast milk only during the first six months had lower levels of vitamin B12, vitamin B6 (PLP), and vitamin B2 compared with the infants who received additional multivitamins.
In addition, 80 percent of all infants had excessively high homocysteine levels and signs of vitamin B12 deficiency during the first six months. Overall, the researchers identified serious deficiencies of one or more B vitamins during the first 12 months, particularly among infants who did not receive supplemental vitamins. Still, B-vitamin deficiencies were also observed in infants who received multivitamin supplements.
The researchers therefore conclude that infants born prematurely and with low birth weight do not receive sufficient B vitamins. The findings also suggest that standard multivitamins for this vulnerable group do not meet the infants’ actual need for several B vitamins. Multivitamin supplements for infants born prematurely and with too low birthweight should therefore be improved. Increased monitoring of the infants’ vitamin status should also be introduced during the early and vulnerable stages of life.

• Preterm infants with low birth weight show significantly greater deficiencies of vitamin B12 (cobalamin), the active form of vitamin B6 (PLP), and vitamin B2 (riboflavin) compared with infants receiving appropriate supplementation
• Standard multivitamins are often of inadequate quality and contain doses that are too low to optimize B-vitamin status in this group
• B-vitamin deficiencies are associated with metabolic changes, including elevated homocysteine levels, which may damage the circulatory system and reduce DNA methylation

References:

Anne-Lise Bjørke-Monsen et al. Exclusive Breastfeeding Is not Ensuring an Adequate Vitamin B Status in Premature Infants with Very Low Birth Weight. Nutrients 2026