Casein Protein
Casein protein is a milk-derived protein characterized by slow digestion and absorption over 6 to 8 hours. Research suggests that pre-sleep casein intake may enhance muscle protein synthesis overnight. Combining casein with whey protein is thought to optimize both immediate and prolonged amino acid delivery.
A well-studied, foundational ingredient

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Effects reported in research
Enhanced overnight muscle protein synthesis (studies report increased synthesis rates with 40g pre-sleep intake)
Sustained amino acid release over several hours (slow absorption may help attenuate muscle breakdown during fasting periods)
Muscle mass preservation during caloric restriction (research indicates contribution to lean mass retention in trained individuals during dieting)
Prolonged satiety (slow digestion characteristics have been associated with appetite suppression in research)
Dosage & timing
- Typically 20 to 40g taken 30 to 60 minutes before sleep.
- Can also be used at other times for post-training recovery.
- Adjust within daily protein intake targets of 1.6 to 2.2g per kilogram of body weight.
Cautions
- •Individuals with milk allergies or lactose intolerance should avoid or consult a doctor before use.
- •Those with kidney conditions should consult a doctor, as high protein intake may place additional strain on the kidneys.
- •Excessive intake may cause gastrointestinal discomfort such as bloating or diarrhea.
- •Pregnant or breastfeeding individuals should consult a doctor before use.
- •Anyone taking medications should check with a doctor or pharmacist prior to use.
Supporting research
Similar supplements
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