Casein
Also known as: micellar casein, casein protein, casein phosphopeptide, CPP-ACP, CPP-ACPF, slow-release protein, milk protein
Effective Dosage
0.4 g/kg body weight per dose based on available study data
What the Science Says
Casein is the primary protein found in cow's milk, making up about 80% of its protein content. It digests slowly, releasing amino acids gradually over several hours, which is why it's often marketed as a 'nighttime' or 'sustained-release' protein. One clinical trial found that micellar casein consumed before a long fasting period (as in Ramadan) helped partially preserve anaerobic power and upper-body strength compared to fasting without protein supplementation. A derivative called casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is also used in dental products to help remineralize early tooth enamel lesions, with clinical trials showing meaningful improvements over 9–12 months.
What It Doesn't Do
Won't fully replace a normal meal or restore athletic performance to non-fasting levels. The dental form (CPP-ACP) is not the same as protein powder — don't confuse them. No evidence from these studies that casein builds more muscle than other proteins in normal training conditions. No proof it burns fat or boosts metabolism. Newer dental scaffolds like phosphorylated nano chitosan outperformed CPP-ACP in remineralization trials — it's not the best option for tooth repair.
Evidence-Based Benefits
Casein is a slow-digesting dairy protein that provides a sustained release of amino acids, making it beneficial for muscle repair and growth, particularly when consumed before sleep. It has been shown to improve muscle mass and strength gains when combined with resistance training.
Strong EvidenceEffective at: 20-40 g daily
Source: auto-research
Absorption & Bioavailability
Moderate — casein forms a gel in the stomach, slowing digestion and amino acid release. This is a feature for sustained delivery but means it absorbs more slowly than whey. Dental CPP-ACP bioavailability is topical and locally acting.
Red Flags to Watch For
- Not suitable for people with milk protein allergies or lactose intolerance — casein is a dairy-derived protein and a common allergen
- Dental CPP-ACP products are a completely different application from protein supplements — marketing may blur these distinct uses
- The athletic performance benefit in the provided study was only partial and tested under Ramadan fasting conditions — results may not generalize to typical training
- Some reviews note mixed signals around dairy protein consumption and breast cancer risk, though causality is not established
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: 2026-04-06