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Protein · Evidence Moderate

Casein Protein

A slow-digesting dairy protein sometimes used before extended fasting windows.

Dosage

30–40 g

Timing

Before sleep or before long gaps between meals

Evidence

Moderate

Overview

Casein is a slow-digesting milk protein. Its unique property is a prolonged amino-acid rise, but the practical advantage over other complete proteins is small when overall daily intake is on track.

Benefits

  • Sustained amino acid release
  • Convenient before overnight fasts

Best for

Muscle preservationOvernight satiety

Stacks with

Side effects

  • GI discomfort in people sensitive to dairy or lactose

Warnings & cautions

  • Contains dairy — avoid if you have a milk-protein allergy.

Drug & condition interactions

  • No significant drug interactions at food-level intakes.

Evidence notes

Casein raises amino acids over a longer window than whey. Practical benefit versus whey is small when total daily protein is adequate.

Research references

  • [1] Res PT et al. Protein ingestion before sleep improves postexercise overnight recovery. Med Sci Sports Exerc, 2012; 44:1560–1569

Medical disclaimer

This page is for general educational purposes only and is not medical advice. Individual response to supplements varies. Consult a licensed healthcare provider before starting any supplement — especially if you are pregnant, breastfeeding, under 18, taking prescription medication, or managing a medical condition.

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