Brewer's Yeast (Inactive) and breast milk supply

What 3 graded rows on brewer's yeast (inactive) agree on for breast milk supply, and where they differ. Counted side by side, never averaged.

Consensus finder Rows from the Brewer's Yeast (Inactive) page, reviewed Oct 21, 2026 How it decides

What the rows agree on

Each block and row is one graded row from the Brewer's Yeast (Inactive) page, with its PubMed record.

Your question

Breast milk supply3

Supplement

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Brewer's Yeast (Inactive) and breast milk supply

3 rows · 349 people

Mostly no difference: 2 of 3 rows, and most of the people. 1 had mixed results.

No difference or mixed

Improved

Each block is one evidence row, sized by how many people it enrolled, with its grade inside. Outlined: mixed results.

Grade D× 1
No effect× 2

Rows: 3
Trials: 3
People: 349

What the rows share

From the rows

The best-graded row, grade D, is a randomized trial of 68 people (2025) and reported mixed results. 2 rows are graded No effect, our grade for adequately powered trials that found no effect.

The rows run from 68 to 176 people, published from 2023 to 2026: 3 single studies.

The rows

2 no difference · 1 mixed

No effectMilk production rate with lactation cookies · No difference
RCT · n 176 · 2023 · Exclusively lactating US parents of healthy 2-month-old infants
56.5 g of cookies a day · 1 month
Milk production rate rose 5.5 mL/h with lactation cookies and 5.8 mL/h with ordinary cookies (difference P = 0.948); perceived insufficient milk and self-efficacy also did not differ.
Row on the Brewer's Yeast (Inactive) page · PubMed 36921902 (opens PubMed)
No effectExpressed breast milk volume after preterm birth · No difference
RCT · n 105 · 2026 · Mothers in 3 Australian neonatal units who gave birth before 34 weeks (36 on brewer's yeast, 35 beta-glucan, 34 placebo)
Capsules daily (dose not stated in the abstract) · 7 days
Daily expressed milk on day 7 was 94 mL/day higher than placebo, but the 95% CI ran from -51 to 239 mL/day, so there was no clear effect; side effects were similar across groups.
Row on the Brewer's Yeast (Inactive) page · PubMed 42680572 (opens PubMed)
Grade DPerceived milk supply and milk sugars in breastfeeding women · Mixed
RCT · n 68 · 2025 · Breastfeeding women with a healthy infant aged 1 to 7 months (New Zealand)
5 g a day · 4 weeks
Human milk oligosaccharides (the primary outcome) did not change; 65% vs 35% on placebo perceived more milk (p < 0.05), and formula use at 6 months was 4% vs 27% (p < 0.05).
Row on the Brewer's Yeast (Inactive) page · PubMed 40932299 (opens PubMed)

Read onRead the full evidenceThe full evidence chapter on its page, with every outcome and its sources.