Skip to main content
SupplementScience

Types of Protein (Whey & Casein): Forms & Bioavailability

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Forms Comparison

FormBioavailabilityBest For
Whey Protein Concentrate (WPC 80)HighCost-effective — 80% protein; retains some lactose and fat; best flavor
Whey Protein Isolate (WPI 90+)Very HighHigher protein per gram (90%+), lower lactose — ideal for lactose-sensitive individuals
Whey HydrolysateVery High (pre-digested)Fastest absorption — pre-digested peptides; bitter taste; marginally faster than isolate
Micellar CaseinHigh (slow release)Before bed — forms a gel in the stomach for sustained amino acid release over 6-8 hours
Casein HydrolysateHigh (fast for casein)Faster-digesting casein — partially defeats the slow-release purpose; niche use

Whey Protein Concentrate (WPC 80)

Bioavailability: High. Best for: Cost-effective — 80% protein; retains some lactose and fat; best flavor.

Whey Protein Isolate (WPI 90+)

Bioavailability: Very High. Best for: Higher protein per gram (90%+), lower lactose — ideal for lactose-sensitive individuals.

Whey Hydrolysate

Bioavailability: Very High (pre-digested). Best for: Fastest absorption — pre-digested peptides; bitter taste; marginally faster than isolate.

Micellar Casein

Bioavailability: High (slow release). Best for: Before bed — forms a gel in the stomach for sustained amino acid release over 6-8 hours.

Casein Hydrolysate

Bioavailability: High (fast for casein). Best for: Faster-digesting casein — partially defeats the slow-release purpose; niche use.

Full Protein (Whey & Casein) Guide

References

  1. (). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength. British Journal of Sports Medicine. DOI
  2. (). Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise. Journal of Applied Physiology. DOI
  3. (). Protein ingestion before sleep improves postexercise overnight recovery. Medicine & Science in Sports & Exercise. DOI