Researchers from four countries measured the levels of B vitamins in breast milk from healthy mothers during the first 8.5 months of breastfeeding. They found that some B vitamins in breast milk are lower than what experts previously thought, while others are higher. This new information helps doctors and health experts better understand what babies get from breast milk and whether they need extra vitamin supplements. The study used advanced laboratory techniques to get precise measurements of eight different B vitamins, providing updated reference values that can be used worldwide.

The Quick Take

  • What they studied: How much of each B vitamin is actually present in breast milk from healthy mothers around the world
  • Who participated: Well-nourished mothers from Bangladesh, Brazil, Denmark, and The Gambia who were tracked during their first 8.5 months of breastfeeding
  • Key finding: Some B vitamins in breast milk are much lower than experts previously believed (especially vitamins B1, B2, and B6), while others match or exceed previous estimates. This means babies may be getting less of certain B vitamins from breast milk than doctors thought.
  • What it means for you: If you’re breastfeeding or planning to, this research may help your doctor decide whether your baby needs B vitamin supplements. However, this is just one study, and you should talk to your pediatrician about your specific situation before making any changes.

The Research Details

Researchers collected breast milk samples from healthy mothers in four different countries over 8.5 months. They used three different advanced laboratory methods to measure eight different B vitamins with high precision. The first method (UPLC-MS/MS) measured five B vitamins at once, a second method measured choline, a third measured vitamin B1, and a fourth measured vitamin B12. By measuring milk from mothers in different parts of the world, the researchers could create standard reference values—basically, a baseline of what’s “normal” in breast milk.

The researchers then compared their new measurements to the numbers that the Institute of Medicine (a major U.S. health organization) had been using to set recommendations for how much B vitamins babies need. This comparison showed whether the old numbers were accurate or needed updating.

Using mothers from multiple countries was important because it helps ensure the results apply to different populations, not just one group of people.

Accurate measurements of what’s actually in breast milk are crucial for making good recommendations about infant nutrition. If doctors think there’s more of a vitamin in breast milk than there actually is, they might not recommend supplements when babies need them. This study provides updated, precise measurements using modern laboratory technology that’s much more accurate than older methods.

This study has several strengths: it included mothers from four different countries (making results more broadly applicable), used advanced laboratory techniques for accurate measurements, and focused on well-nourished mothers (providing a good baseline). However, the study only included healthy, well-nourished mothers, so results might be different for mothers with poor nutrition. The sample size wasn’t specified in the abstract, which makes it harder to assess how many mothers were studied. The research was published in a peer-reviewed journal, meaning other experts reviewed it before publication.

What the Results Show

The study found important differences between what’s actually in breast milk and what experts previously thought. For vitamins B1, B2, and B6, the amounts in breast milk were much lower than the old estimates—less than 60% of what the Institute of Medicine had been using. This is significant because it means babies may be getting less of these vitamins from breast milk alone than previously believed.

For vitamins B3, B12, and choline, the amounts were closer to the old estimates, ranging from 60% to 100% of what experts had been using. This means these vitamins were roughly in line with previous understanding.

Interestingly, for pantothenic acid and biotin, the amounts in breast milk were actually slightly higher than the old estimates—between 100% and 125%. This suggests babies may be getting more of these vitamins from breast milk than doctors thought.

When researchers calculated how much of each B vitamin babies actually get from breast milk during the first six months, they found that babies get only 29-45% of the recommended amount for vitamins B1 and B2, suggesting these might need supplementation.

The study provided percentile curves for all B vitamins, which is a way of showing the range of normal values. This allows other researchers to compare their own measurements and see if they’re in the expected range. The research also showed that B vitamin levels in breast milk can vary between mothers, which is important information for understanding individual differences.

This study updates reference values that had been in place for many years. The previous estimates came from older studies using less precise laboratory methods. By using modern technology and studying mothers from multiple countries, this research provides more accurate baseline values. The findings suggest that some previous recommendations for infant B vitamin intake may need to be reconsidered, particularly for vitamins B1 and B2.

The study only included well-nourished mothers, so the results may not apply to mothers with poor nutrition or vitamin deficiencies. The specific number of mothers studied wasn’t mentioned in the abstract, making it unclear how large the study was. The study was conducted in specific countries, and while this provides international perspective, results might vary in other populations. Additionally, this is one study providing reference values; more research may be needed to fully understand how these findings should change infant nutrition recommendations.

The Bottom Line

Based on this research, pediatricians may need to reconsider B vitamin supplementation recommendations for breastfed babies, particularly for vitamins B1 and B2 (moderate confidence). Parents should not make changes to their baby’s nutrition based on this study alone—instead, discuss these findings with your pediatrician, who can assess your baby’s individual needs. For breastfeeding mothers, maintaining good nutrition remains important for milk quality (high confidence).

Pediatricians and lactation specialists should pay attention to these findings when making recommendations about infant nutrition and supplementation. Parents of breastfed babies should be aware that their pediatrician may have updated recommendations based on this research. Healthcare systems developing infant nutrition guidelines should consider updating their recommendations. Mothers with poor nutrition or vitamin deficiencies should discuss supplementation with their doctor, as this study focused on well-nourished mothers.

If a baby needs B vitamin supplementation based on these findings, benefits would typically be seen over weeks to months as the vitamin levels build up in the baby’s body. This isn’t something with immediate visible changes, but rather supports normal growth and development over time.

Want to Apply This Research?

  • If your pediatrician recommends B vitamin supplementation for your breastfed baby, track the supplement doses given (date, time, and which B vitamins) and note any changes in your baby’s energy level, feeding patterns, or overall development.
  • If you’re breastfeeding, use the app to track your own B vitamin intake through food (eggs, dairy, meat, whole grains, nuts) to support healthy milk production. If your doctor recommends baby supplements, set reminders in the app to give them consistently.
  • Track your baby’s growth measurements (weight, length) at regular pediatric visits to ensure healthy development. If supplementation is recommended, monitor for any changes in feeding behavior or energy level. Keep notes on any questions to ask your pediatrician at the next visit.

This research provides updated information about B vitamin levels in breast milk but should not be used to make decisions about your baby’s nutrition without consulting your pediatrician. Every baby’s nutritional needs are different based on their health status, growth, and individual circumstances. If you’re concerned about your baby’s B vitamin intake or considering supplements, speak with your healthcare provider before making any changes. This study focused on well-nourished mothers, so results may not apply to all populations. Always follow your pediatrician’s recommendations for your child’s specific situation.