Types of protein powder
Concentrate, isolate, hydrolysate, casein, plant blends and collagen: how they actually differ, which to pick, and when the powder adds nothing over food.
Protein powder is dehydrated food, not an ergogenic aid. It does one specific job: getting you to your daily protein total when eating does not, with fewer calories and less logistical effort than the alternative. Everything else attributed to it — exact timing, form, absorption speed — moves far less than it occupies in the advertising.
Supplemental protein helps, and stops helping once the total is covered
Morton’s meta-analysis, over 49 studies and almost 2,000 participants, found a small but real benefit of protein supplementation on lean mass and strength in people doing resistance training. The same work sets the plateau: above roughly 1.6 g/kg/day of total protein, adding more adds nothing. In other words, the tub’s effect is the effect of hitting the total, not of the brand.
The theory of how much protein is in the other guide
How many grams a day by goal, how to split it and why it goes up in a deficit, in planning your calories and recovery. This chapter starts where that one ends: you know your number and you are 40 g short.
How one protein compares to another
Three things separate one protein source from another, and only three. The rest are adjectives.
- Essential amino acid profile
- If one is missing, the protein is limited by it
- Leucine content
- 2-3 g per serving is the usual threshold
- Digestibility (DIAAS)
- How much of what you eat actually arrives
Cereals are short on lysine; legumes on methionine. Mixing them fixes it.
It is the amino acid that triggers the protein synthesis signal. Whey is ~11%; soy ~8%; wheat, less.
The FAO’s DIAAS scale replaced the old PDCAAS. Dairy and egg above 1.0; plant sources below.
Differences between sources are offset by raising the dose
Tang’s classic trial compared whey, casein and soy and found a larger acute protein synthesis response with whey. But Pinckaers’ review of plant protein shows that disadvantage is corrected with a slightly larger dose or by blending sources, and Hevia-Larraín’s trial, which matched total protein between vegans and omnivores over twelve weeks of training, found no differences in mass or strength gains. Source matters per serving; the total matters for the result.
The dairy ones: whey and casein
Milk is 80% casein and 20% whey. Both are complete, highly digestible proteins; they differ in how fast they reach the blood, which is a minor detail with even more minor practical implications.
| Type | Protein per 100 g | What sets it apart | Who for |
|---|---|---|---|
| Whey concentrate (WPC) | 70-80% | The least processed and cheapest per gram. Retains some lactose and fat | The default choice for almost everyone |
| Whey isolate (WPI) | 85-90% | Filtered: almost no lactose or fat. Costs 30-50% more | Lactose intolerance or a very tight calorie deficit |
| Whey hydrolysate (WPH) | 80-90% | Pre-digested. Slightly faster absorption, worse taste, high price | Almost nobody. No demonstrated advantage in body composition |
| Casein (micellar) | 75-85% | Clots in the stomach: slow release over hours. Very thick | A night-time serving or widely spaced meals |
| Milk blend / MPC | 70-85% | Whey and casein in milk proportions | A reasonable and often cheaper alternative |
Isolate: when it is worth paying for
The real difference between concentrate and isolate is lactose, fat and a few grams of protein per 100. If concentrate sits well with you, isolate is money for a difference you will not see in the mirror. If it bloats you, isolate solves the problem and is worth it.
The plant ones
They have stopped being plan B. The key is not buying a single isolated source: blends cover the amino acid profile each one lacks on its own.
- Soy: the only plant source with a complete profile on its own and good digestibility. The concern about isoflavones and testosterone is not supported at dietary doses.
- Pea: rich in lysine and branched-chain amino acids, low in methionine. It is the base of almost every commercial blend.
- Rice: the natural complement to pea — high in methionine, low in lysine. Pea + rice comes close to whey’s profile.
- Hemp, pumpkin, sunflower: worse profile and less protein per 100 g. Fine as part of a blend, not as the only source.
The practical rule for plant protein
Blend at least two sources and take a serving 20-30% larger than you would with whey: about 30-40 g instead of 25. With that, the available evidence cannot tell the twelve-week outcomes apart.
Collagen: a different thing, a different use
Collagen is no good for building muscle, and may be good for connective tissue
Collagen is an incomplete protein: it lacks tryptophan and is very low in leucine, so as a protein for hypertrophy it is one of the worst things you can buy. The interesting line is different: Shaw’s work found that 15 g of gelatin with vitamin C, taken an hour before a short mechanical stimulus, increased markers of collagen synthesis. Evidence on clinical outcomes — tendinopathy, joint pain — remains limited and the AIS keeps it in group B.
Do not count collagen inside your daily protein
Many products add the grams of collagen to the protein total on the label. For muscle purposes those grams do not count. If you take 20 g of collagen, your useful protein for the day is still what it was before.
When and how much to take
The area with the most noise and the least measured effect. The honest summary: split the day sensibly and forget the clock.
- Per serving
- 0.4-0.55 g/kg
- Servings a day
- 3-5, spread out
- Around training
- Within a window of hours
- Before bed
- 30-40 g if dinner was early
About 25-40 g for most people. More in one sitting is not wasted, but returns less.
Every 3-4 hours is what works most often in distribution studies.
The 30-minute "anabolic window" does not survive the timing meta-analysis once total protein is matched.
The one slot where casein has an argument of its own.
Timing matters little once the total is covered
Schoenfeld, Aragon and Krieger’s meta-analysis on protein timing found that the apparent effect of taking protein near training disappears once total daily intake is adjusted for. The later review on how much protein can be used in a single meal reaches the same place from the other side: sensible distribution matters, the stopwatch does not.
What to check when buying protein
These five points rule out almost everything that does not belong on a shop shelf.
- Grams of protein per 100 gBelow 70% you are paying filler prices for protein.
- Price per 100 g of protein, not per kilo of tubIt is the only honest comparison between brands and formats.
- No free amino acids high in the ingredient listGlycine or taurine near the top usually means amino spiking.
- A blend of sources if it is plant-basedPea + rice, or any combination that closes the profile.
- A batch-tested mark if you competeInformed Sport or NSF Certified for Sport (why).
Takeaways
- Powder is for hitting the daily total; above ~1.6 g/kg there is nothing more to gain.
- Whey concentrate by default; isolate only for lactose or very tight calories; hydrolysate, almost never.
- Plant proteins work just as well by blending sources and raising the serving 20-30%.
- Collagen is a different thing: it does not count as muscle protein and its use is connective tissue.
- Split 3-5 servings of 25-40 g; the stopwatch around training does not change the outcome.
Sources for this chapter
- [1]Morton RW, Murphy KT, McKellar SR, et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine. meta-analysis
- [2]Jäger R, Kerksick CM, Campbell BI, et al. (2017). International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition. position stand
- [3]Tang JE, Moore DR, Kujbida GW, Tarnopolsky MA, Phillips SM (2009). Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men. Journal of Applied Physiology. trial
- [4]Pinckaers PJM, Trommelen J, Snijders T, van Loon LJC (2021). The Anabolic Response to Plant-Based Protein Ingestion. Sports Medicine. review
- [5]Hevia-Larraín V, Gualano B, Longobardi I, et al. (2021). High-Protein Plant-Based Diet Versus a Protein-Matched Omnivorous Diet to Support Resistance Training Adaptations: A Comparison Between Habitual Vegans and Omnivores. Sports Medicine. trial
- [6]Devries MC, Phillips SM (2015). Supplemental protein in support of muscle mass and health: advantage whey. Journal of Food Science. review
- [7]FAO (2013). Dietary protein quality evaluation in human nutrition: report of an FAO expert consultation (DIAAS). FAO. official guideline
- [8]Schoenfeld BJ, Aragon AA, Krieger JW (2013). The effect of protein timing on muscle strength and hypertrophy: a meta-analysis. Journal of the International Society of Sports Nutrition. meta-analysis
- [9]Schoenfeld BJ, Aragon AA (2018). How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. Journal of the International Society of Sports Nutrition. review
- [10]Kerksick CM, Arent S, Schoenfeld BJ, et al. (2017). International society of sports nutrition position stand: nutrient timing. Journal of the International Society of Sports Nutrition. position stand
- [11]Shaw G, Lee-Barthel A, Ross ML, Wang B, Baar K (2017). Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. American Journal of Clinical Nutrition. trial
- [12]Australian Institute of Sport (2025). AIS Sports Supplement Framework: clasificación ABCD de suplementos. Australian Institute of Sport. official guideline