According to Gram Research analysis, brewer’s yeast and beta-glucan supplements do not significantly increase breast milk production in mothers of premature babies. A 2026 randomized controlled trial of 105 mothers found that those taking brewer’s yeast produced only 94 milliliters more milk per day than placebo, a difference that wasn’t statistically meaningful, while beta-glucan showed no benefit at all. Both supplements were safe and well-tolerated, but evidence-based strategies like frequent milk expression remain the most reliable approach.
When babies are born very early, mothers often struggle to produce enough breast milk. Researchers tested whether taking brewer’s yeast or beta-glucan supplements could help increase milk production in mothers of preterm babies. In a study of 105 mothers at Australian hospitals, those taking either supplement for one week produced about the same amount of milk as mothers taking a placebo. While the supplements were safe and well-tolerated, they didn’t show a meaningful benefit for boosting milk supply in the short term.
Key Statistics
A 2026 randomized controlled trial published in Archives of Disease in Childhood involving 105 mothers of premature babies found that brewer’s yeast increased daily breast milk production by only 94 milliliters compared to placebo, a difference that was not statistically significant.
In the same 2026 trial of 105 mothers, beta-glucan supplementation actually resulted in 25 milliliters less milk per day than placebo, with no statistical significance, suggesting no benefit for milk production.
The 2026 BLOOM trial found that both brewer’s yeast and beta-glucan supplements were well-tolerated with similar side effect rates across all groups, indicating safety but not efficacy for boosting breast milk supply in premature births.
The Quick Take
- What they studied: Whether brewer’s yeast or beta-glucan supplements could help mothers of premature babies produce more breast milk
- Who participated: 105 mothers from three Australian hospitals who gave birth before 34 weeks of pregnancy between August 2022 and April 2024. Mothers were divided into three equal groups: one taking brewer’s yeast, one taking beta-glucan, and one taking placebo pills
- Key finding: After 7 days of taking supplements, mothers taking brewer’s yeast produced about 94 milliliters more milk per day than the placebo group, but this difference wasn’t statistically significant. The beta-glucan group actually produced slightly less milk than placebo
- What it means for you: If you’re a mother of a premature baby, brewer’s yeast and beta-glucan supplements don’t appear to be reliable ways to boost milk production based on current evidence. Talk with your healthcare team about proven strategies for increasing milk supply
The Research Details
This was a randomized controlled trial, which is considered one of the strongest types of medical research. Researchers randomly assigned 105 mothers into three equal groups within 72 hours of giving birth to premature babies. One group received brewer’s yeast capsules, another received beta-glucan capsules, and the third received placebo (fake) capsules. Neither the mothers nor the researchers knew which group was receiving which treatment, making it a “blinded” study that reduces bias.
All mothers took their assigned capsules for 7 days. On day 7, researchers measured how much breast milk each mother expressed in a 24-hour period. This was the main outcome they were looking for. The researchers also tracked any side effects mothers experienced to make sure the supplements were safe.
This design is strong because random assignment helps ensure the groups were similar at the start, and the blinding prevents expectations from influencing results. However, the study only lasted one week, so it only measured short-term effects.
This research approach matters because mothers of premature babies face real challenges with milk production, and they need evidence-based solutions. A randomized controlled trial provides stronger evidence than simply asking mothers about their experiences. By comparing supplements to placebo rather than to nothing, researchers could see if any benefits were real or just due to placebo effect. Testing in real hospital settings with actual premature births makes the results more relevant to real-world situations.
This study has several strengths: it was randomized, blinded, and placebo-controlled, which are gold-standard features. It was conducted at reputable tertiary hospitals and published in a peer-reviewed medical journal. However, the sample size of 105 mothers is relatively small, which means the study had limited statistical power to detect smaller effects. The researchers themselves noted this limitation. The study only measured effects over 7 days, so we don’t know if longer use might show different results. Additionally, the confidence intervals around the main findings were wide, meaning there’s considerable uncertainty about the true effect size.
What the Results Show
The main finding was that brewer’s yeast and beta-glucan supplements did not significantly increase breast milk production compared to placebo. Mothers taking brewer’s yeast produced an average of 94 milliliters more milk per day than the placebo group, but this difference had a wide confidence interval (-51 to 239 mL/day), meaning the true effect could be anywhere in that range, including zero or even negative.
The beta-glucan group actually produced 25 milliliters less milk per day than placebo on average, though again this difference was not statistically significant (confidence interval: -173 to 123 mL/day). To put these numbers in perspective, a typical breastfeeding session produces 30-150 milliliters, so even the largest observed difference was relatively modest.
Both supplements were well-tolerated, with similar rates of side effects across all three groups. No serious adverse events were reported. This means that while the supplements didn’t help with milk production, they also didn’t cause harm during the one-week treatment period.
The researchers emphasized that the small sample size means they cannot completely rule out the possibility that a larger study might find a clinically meaningful benefit, particularly for brewer’s yeast. However, based on this evidence, there’s no clear reason to recommend these supplements for boosting milk supply in the immediate postpartum period.
The study tracked maternal side effects as a secondary outcome. Across all three groups, mothers reported similar types and frequencies of side effects, suggesting both supplements were as safe as placebo. This is important because it means any future research wouldn’t need to worry about safety concerns with these supplements in this population.
This is one of the first rigorous randomized controlled trials examining brewer’s yeast and beta-glucan for breast milk production in mothers of premature babies. Previous research on these supplements for milk supply has been limited and often of lower quality. Some smaller studies and anecdotal reports suggested potential benefits, but those studies lacked the rigorous design of this trial. This research provides stronger evidence that contradicts some earlier, less rigorous claims about these supplements’ effectiveness.
The main limitation is the small sample size of 105 mothers, which reduces the study’s ability to detect smaller but potentially meaningful effects. The study only lasted 7 days, so it only shows short-term effects, longer-term use might produce different results. The study included only mothers at Australian tertiary hospitals, so results may not apply to all populations or healthcare settings. Additionally, the study didn’t measure long-term milk production or infant outcomes, only the volume of expressed milk on day 7. Finally, the confidence intervals were quite wide, indicating substantial uncertainty around the true effect sizes.
The Bottom Line
Based on this research, brewer’s yeast and beta-glucan supplements are not recommended as primary strategies for increasing breast milk production after premature birth. Instead, mothers should focus on evidence-based approaches like frequent milk expression (every 2-3 hours), skin-to-skin contact with their baby, adequate hydration and nutrition, and working with lactation consultants. If milk supply remains low, discuss other proven interventions with your healthcare team. These supplements may be safe to use, but they shouldn’t replace established milk-boosting strategies. Confidence level: Moderate (based on one well-designed but small trial).
This research is most relevant to mothers who have given birth prematurely and are struggling with milk production. Healthcare providers caring for these mothers should be aware that these supplements lack strong evidence of benefit. Lactation consultants should know this information when counseling mothers. However, this research doesn’t apply to mothers of full-term babies or those without milk supply concerns. Mothers considering these supplements should discuss them with their healthcare team rather than self-treating.
This study measured effects over just 7 days, so we don’t know how long it would take to see benefits if they existed. Based on the results, mothers shouldn’t expect these supplements to noticeably increase milk production in the first week postpartum. If milk supply is a concern, improvements from evidence-based strategies typically appear within 1-2 weeks of consistent milk expression.
Frequently Asked Questions
Does brewer’s yeast actually help increase breast milk supply after premature birth?
A 2026 trial of 105 mothers found brewer’s yeast increased milk by only 94 mL/day compared to placebo, not a meaningful difference. While safe, it’s not an effective strategy for boosting supply after premature birth.
What supplements can help mothers of premature babies produce more milk?
This research found neither brewer’s yeast nor beta-glucan significantly increased milk production. Evidence-based approaches like frequent milk expression every 2-3 hours, adequate hydration, and working with lactation consultants are more reliable.
Are brewer’s yeast supplements safe for mothers breastfeeding premature babies?
Yes, according to the 2026 BLOOM trial, brewer’s yeast was well-tolerated with side effect rates similar to placebo. However, safety doesn’t mean it’s effective for increasing milk supply.
How long does it take for brewer’s yeast to increase breast milk production?
This study tested brewer’s yeast for only 7 days and found no significant increase in milk production. Longer-term effects are unknown, but evidence-based strategies typically show results within 1-2 weeks.
What’s the best way to increase milk supply when you’ve had a premature baby?
Focus on frequent milk expression every 2-3 hours, skin-to-skin contact with your baby, adequate nutrition and hydration, and working with a lactation consultant. These evidence-based strategies are more effective than supplements.
Want to Apply This Research?
- Track daily expressed breast milk volume in milliliters at the same time each day. Record the total 24-hour output to identify trends over time. Note any supplements or interventions started to correlate with changes in production.
- Instead of relying on supplements, use the app to set reminders for frequent milk expression every 2-3 hours, track hydration intake, and log skin-to-skin contact sessions with your baby. These evidence-based practices are more likely to boost supply.
- Monitor milk production weekly rather than daily to see meaningful trends. Track which milk-boosting strategies correlate with increases in supply. Share this data with your lactation consultant or healthcare provider to adjust your approach based on what’s actually working for you.
This research summary is for educational purposes and should not replace professional medical advice. Mothers of premature babies should consult with their healthcare provider, obstetrician, or lactation consultant before starting any supplements, including brewer’s yeast or beta-glucan. While this study found these supplements safe, they were not shown to effectively increase milk production. Individual circumstances vary, and personalized medical guidance is essential for optimal outcomes for both mother and baby.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.
