Alpha-Lactalbumin
Also known as: α-lactalbumin, ALAC, alpha-lac, α-lac
Effective Dosage
No established dose from provided studies for most uses; 40 g used in sleep studies
What the Science Says
Alpha-lactalbumin is a protein naturally found in breast milk and cow's milk. It is rich in the amino acid tryptophan, which the body uses to make serotonin and melatonin — chemicals involved in sleep and mood. Clinical trials suggest that taking 40 grams before bed may alter sleep architecture and improve next-morning reaction time in trained individuals who have trouble sleeping, though one study found no benefit in a habitual home environment. It is also widely used in infant formula to better mimic the protein composition of breast milk.
What It Doesn't Do
Won't cure insomnia or replace good sleep hygiene. No strong evidence it boosts immunity in formula-fed infants compared to breastfeeding. The bone health data comes from a tiny 6-person case series — not proof it strengthens bones. Lab studies on bioactive peptides and drug delivery are not evidence it works that way in supplements you swallow. No evidence it treats PCOS, diabetes, or heart disease on its own.
Evidence-Based Benefits
Alpha-lactalbumin is a protein naturally found in breast milk and cow's milk. It is rich in the amino acid tryptophan, which the body uses to make serotonin and melatonin — chemicals involved in sleep and mood. Clinical trials suggest that taking 40 grams before bed may alter sleep architecture and improve next-morning reaction time in trained individuals who have trouble sleeping, though one study found no benefit in a habitual home environment. It is also widely used in infant formula to better mimic the protein composition of breast milk.
Weak EvidenceEffective at: No established dose from provided studies for most uses; 40 g used in sleep studies
Source: auto-research
Absorption & Bioavailability
Unknown from provided studies for supplemental use; as a whey protein fraction it is generally considered well-digested, but no direct bioavailability data was reported in the provided papers
Red Flags to Watch For
- People with cow's milk allergy should avoid it — one MMR vaccine study confirmed allergic reactions, including anaphylaxis, are possible with alpha-lactalbumin-containing products
- The 40 g dose used in sleep studies is a very large protein load — far higher than what most supplements provide, making label doses potentially ineffective
- Bone health and PCOS claims are based on very small pilot studies (6 patients and 24 patients respectively) with no control groups for alpha-lactalbumin specifically
- Most exciting research (drug delivery nanoparticles, DPP-4 inhibitory peptides, fat-reducing microneedles) is pre-clinical lab work — not evidence for oral supplements
Products Containing Alpha-Lactalbumin
See how Alpha-Lactalbumin is used in these analyzed products:
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-09