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Moderate evidenceSleep & relaxation

Milk Peptides (Lactium)

Lactium is a tryptic hydrolysate of bovine alpha-s1 casein containing alpha-casozepine, a peptide that binds GABA-A benzodiazepine sites without benzodiazepine dependence. Several small randomized trials show modest reductions in stress symptoms and sleep disturbance — real but small effects, from a research base that is largely manufacturer-linked.

What the science says

  • Reduces stress-related symptoms in small randomized trials Moderate evidence

    A double-blind placebo-controlled trial in women with stress-related symptoms gave 150 mg/day alpha-s1 casein hydrolysate for 30 days and found significant improvement in digestive, cardiovascular, emotional and social domains of a stress symptom scale versus placebo. An earlier crossover study in healthy men showed 400 mg blunted systolic blood pressure and cortisol responses to a standardized mental and physical stress challenge.

  • Improves subjective sleep quality in people with disturbed sleep Moderate evidence

    A double-blind randomized placebo-controlled crossover study of alpha-s1 casein hydrolysate in adults with sleep disturbance reported improvements in sleep quality measures over placebo. Effects were modest and largely subjective (questionnaire-based) rather than polysomnographic, and sample sizes across the Lactium literature are in the tens, not hundreds.

  • Binds benzodiazepine sites without benzodiazepine liabilities Moderate evidence

    Mechanistic work shows alpha-casozepine's anxiolytic-like effect in animals depends on GABA-A receptor benzodiazepine binding sites — the effect is abolished by flumazenil-sensitive manipulations — yet unlike benzodiazepines it does not produce sedation, tolerance, amnesia or dependence in animal models. This makes it pharmacologically interesting, though animal receptor mechanism does not by itself predict clinical magnitude in humans.

  • The research base is small and heavily industry-linked Limited evidence

    Most human Lactium trials involve the ingredient manufacturer, use fewer than 60 participants, run 2-4 weeks, and rely on self-report scales. No large independent replication or meta-analysis exists. The honest read: plausible mechanism, consistent small positive results, weak independence — treat it as promising rather than established.

Dosage & safety

Studied doseHuman trials used 150 mg/day for 30 days (stress symptoms) or 200-400 mg as a single dose before a stressor. Sleep studies used similar daily doses in the evening. Commercial products generally supply 150-300 mg of Lactium per serving, which matches the studied range — unusual among supplements. Allow 2-4 weeks for daily-use effects.
SafetyWell tolerated in trials, with no notable adverse events at 150-400 mg/day; it is a food-derived milk protein hydrolysate. It contains milk protein, so it is unsuitable for people with cow's milk protein allergy — lactose-intolerant people are generally fine, as the product is peptide, not lactose. Theoretical additive sedation with benzodiazepines, alcohol, or other CNS depressants; caution if you drive shortly after an evening dose. No pregnancy or breastfeeding data. Not banned in sport. Do not use as a substitute for treatment of clinical anxiety or insomnia.

Scientific references

Where to buy

Protocol for Life Balance, Clinical Stress Relief , 60 Veg Capsules

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