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Compound

Casein Protein

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Casein Protein. Slow-digesting milk protein providing sustained amino acid release, popular pre-sleep.

How it works. Forms clot in stomach producing sustained 6–8h amino acid release.

What the research supports. 1 graded claims. Strongest: Pre-sleep casein increases overnight MPS and morning recovery (moderate).

How much to take. Typical dose: 30–40 g pre-sleep.

Side effects and interactions. 1 medication interaction listed. No serious side effects listed at normal doses.

Stacking. Pairs well with Creatine monohydrate, Whey or EAAs.

Common forms. Available as Micellar casein, Calcium caseinate.

Key studies. 8 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried Casein Protein. Anecdotes are not medical advice.

Casein Protein. Slow-digesting milk protein providing sustained amino acid release, popular pre-sleep.

Key compound: L-leucineC6H13NO2 · 131.17 g/mol

What it is

Slow-digesting milk protein providing sustained amino acid release, popular pre-sleep.

Food sources

Dairy

Goals

Muscle GrowthRecovery Optimization

How it works

Forms clot in stomach producing sustained 6–8h amino acid release.

Pathways

  • Sustained MPS substrate

Effects

  • +Overnight muscle protein synthesis supports

What the research supports

Pre-sleep casein increases overnight MPS and morning recoverymoderate

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
30–40 g pre-sleep
TimingConsistent daily timing recommended; split larger doses if GI tolerance is a concern.
With foodWith a meal containing fat for fat-soluble compounds; otherwise either.
Best formMost evidence is based on the micellar casein form.
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Side effects & interactions

Common side effects

  • Bloating

Medication interactions

Prescription medications (general)minor

Always disclose Casein Protein use to your prescriber — additive, antagonistic, or pharmacokinetic interactions are possible.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

  • Creatine monohydrateFoundational support for strength, power, and lean mass.
  • Whey or EAAsProvides amino acid substrate for muscle protein synthesis.

Common forms

  • Micellar casein
  • Calcium caseinate

Key studies

8 studies cited in total.

PubMed: Casein Protein — Pre-sleep casein increases overnight MPS and morning recovery ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Casein Protein and "Pre-sleep casein increases overnight MPS and morning recovery". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Casein Protein — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Casein Protein and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Casein Protein — meta-analysis ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Casein Protein and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

Discussion

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