Actually, the difference is vast!
What is Whey Protein?
Whey is a complete protein derived from milk during the cheesemaking process. Being “complete” means it contains all nine essential amino acids your body can’t make on its own. It’s especially rich in leucine, a branched-chain amino acid (BCAA) that plays a key role in stimulating muscle protein synthesis (MPS) — the process your body uses to repair and build muscle.
Best for: Muscle growth, recovery after exercise, supporting overall protein intake
Absorption: Rapidly digested and absorbed – helps meet meal and post-workout targets quickly (exactly what you want!)
Forms available:
- Whey isolate (purest form and lactose free)
- Whey concentrate
- Hydrolysed whey
What is Collagen Protein?
Collagen is the most abundant protein in the human body, found in skin, hair, nails, joints, tendons, and ligaments.
It is a structural protein providing both strength and structure – via joints, cartilage, and tendons, as well as elasticity for skin and strength for hair and nails.
Collagen supplements (usually labelled as “collagen peptides” or “hydrolysed collagen”) are made from animal connective tissue, such as bovine hide or fish skin.
Unlike whey, collagen is not a complete protein — it lacks tryptophan and has lower levels of certain essential amino acids. However, it’s uniquely rich in glycine, proline, and hydroxyproline, which are the key building blocks your body uses to produce collagen.
Best for:
- Skin elasticity
- Joint health
- Reducing signs of aging
- Supporting tendons and ligaments
Absorption: Easily digested and dissolves well in hot or cold liquids
Forms available:
- Bovine
- Marine
- Chicken collagen
- Types I and III – best for hair, skin, and nails
- Type II – for joints and tendons
How to Best Use
Whey is a little more difficult to use – it really is best in cold foods like yoghurt, cold milk drinks, iced latte, smoothies, or even whizzed into cold water.
I like to add it to protein yoghurt (it actually thins the yoghurt down), then add berries and a seed mix for a delicious high-protein breakfast.
Collagen, on the other hand, dissolves in either hot or cold liquids and may be added to drinks or foods. It’s easy to add to your morning coffee or tea, or your drink bottle throughout the day.
Need help planning protein-rich meals after surgery? Check out our New Beginnings Program for ongoing post-op nutrition support.
Supporting Recovery After Bariatric Surgery
Following bariatric surgery, your protein needs increase significantly to support wound healing, muscle preservation, immune function, and overall recovery. Because your stomach capacity is reduced, it’s often difficult to meet these needs through food alone — especially in the early months after surgery. That’s where supplements like whey and collagen become essential tools. They’re convenient, well-tolerated, and easy to incorporate into your daily routine. Understanding the difference between them helps you make informed choices and stay on track with your recovery, strength goals, and long-term weight management success.
The Bottom Line
Choose whey protein if your priority is building or maintaining muscle, supporting sports performance, or boosting daily protein intake.
Choose collagen protein if your focus is joint support, skin health, or healthy aging.
Whey should provide at least 80% and collagen 20% of your total daily protein target.
It is very difficult to meet ideal protein targets after bariatric surgery — especially in the first 3–4 months.
Whey protein is a valuable addition to your meal plan at these times and can quite easily help you meet your protein target.
The ideal time to use WPI is early in the day, as this is when we need it most for muscle maintenance.
Example: a pre-breakfast drink and then added to your breakfast meal (see above).