Protein Powder: How to Choose the Right Type and Save Money

The main protein powder types are whey concentrate, whey isolate, whey hydrolysate, casein, and plant proteins such as soy, pea, rice and blends. They differ mainly in how much of each scoop is actually protein, how much lactose, fat and fibre comes with it, texture and price. To compare any two tubs fairly, divide protein per serve by serving size to get the protein percentage, check the ingredient list starts with the protein named on the front, then work out the cost per 100 g of protein.

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This guide is about reading the tub. It compares the protein types side by side, explains the label numbers that matter, flags tricks such as amino spiking, and gives a checklist for choosing. It does not tell you how much protein to eat or claim that any powder does anything for your health. For background on protein needs with age, see protein after forty.

At a glance

• Protein percentage beats “grams per serve”: 25 g in a 30 g scoop is about 83 per cent protein; 25 g in a 40 g scoop is about 63 per cent.
• Isolate is more filtered than concentrate: usually 90 per cent protein or more, with little lactose or fat.
• Plant powders vary: soy isolate is comparable to whey isolate on the panel; pea-rice blends are common because the two complement each other’s amino acids.
• Watch for amino spiking: added cheap amino acids can inflate the protein figure.
• Talk to your doctor or pharmacist if you have kidney disease, a milk or soy allergy, or take regular medicines.

Protein powder types compared

Type	Typical labelled protein by weight	Lactose and fat	Texture and taste	Worth knowing
Whey protein concentrate (WPC)	Commonly about 70 to 80%, though products as low as about 35% exist	Contains some lactose and fat	Creamy, mild	Usually the cheapest whey per gram of protein
Whey protein isolate (WPI)	Usually 90% or more	Very little lactose or fat	Thinner, clean taste	Often chosen by people sensitive to lactose; not lactose-free unless stated
Whey protein hydrolysate (WPH)	Similar to its source material	Similar to its source	Noticeably more bitter	Most expensive whey; often blended
Micellar casein	About 75 to 85%	Low	Thickens strongly in liquid	Often marketed for puddings and overnight mixes
Milk protein concentrate	Varies	Varies	Creamy	Roughly the natural milk ratio of about 80 casein to 20 whey
Soy protein isolate	About 90%	Dairy-free	Smooth, slightly beany	Contains all nine essential amino acids
Pea protein	About 75 to 85%	Dairy-free	Earthy, can be gritty	Relatively low in methionine; often blended with rice
Rice protein	About 80%	Dairy-free	Slightly chalky	Relatively low in lysine; usually the partner in pea-rice blends
Hemp and seed powders	Often around 50%	More fibre and fat	Nutty, grainy	Food-first products; look expensive on protein per dollar

These are typical labelled ranges across products on sale, not fixed standards. The arithmetic below lets you check any specific tub yourself.

The number that matters: protein percentage

Every tub carries a nutrition or Supplement Facts panel. Find serving size in grams and protein per serve in grams, and divide the second by the first. That is the protein percentage by weight, and it lets you compare any two tubs.

Scoop sizes vary from about 25 g to over 45 g. A larger scoop is a serving convention, not a quality signal, and it is the easiest way for two products to both say “25 g protein per serve” while being quite different. The rest of the scoop may be carbohydrate, fat, flavouring, thickener, sweetener or moisture.

A useful shortcut: in Australia, New Zealand, the UK and the European Union, food labels generally include a per 100 g column. The protein figure per 100 g is the protein percentage, so you can read it straight off. United States labels usually give per serve only, so you need the division.

Whey in more detail

Whey is the liquid part of milk left after cheese-making. Dried and filtered, it becomes whey protein powder, and the three names on the shelf describe how far the filtering went.

Concentrate

The least processed and usually the cheapest. The remainder is mostly lactose, some fat and minerals. A concentrate at around 3 to 5 g carbohydrate per serve is typical.

Isolate

Further filtered to remove most of the lactose and fat; carbohydrate is often under 1 g per serve. Isolate costs more per tub, but whether it costs more per gram of protein depends on the two tubs in front of you.

Hydrolysate

Whey that has been treated with enzymes to break some protein chains into shorter fragments. The panel rarely states the degree of hydrolysis; if it is mentioned, it is usually in the marketing copy.

Label check for whey: the first ingredient should match the whey type advertised. If “whey protein concentrate” appears first in a tub marketed as isolate, the product is a blend.

Plant proteins in more detail

Plant powders are extracted from legumes, grains or seeds. Soy is a complete protein and has long been the plant reference point. Pea and rice are often blended because pea is relatively low in methionine and rice relatively low in lysine, so together they balance each other. A single-source pea powder is not “incomplete” in any dramatic sense, but an amino acid panel, where printed, shows the pattern.

Plant labels are also worth checking for fibre, which can be substantial, and sodium, which is often higher than in dairy powders because of processing. Because plants take up minerals from soil, independent batch testing for contaminants such as heavy metals is worth looking for in any powder you use regularly.

Amino acid panels and amino spiking

Some tubs print a full amino acid profile. It is optional on most labels and its absence does not mean anything is hidden. When present, people often look at the essential amino acids and leucine. The NIH Office of Dietary Supplements notes that whey contains more leucine than casein or soy, which is why some products add free leucine or a “BCAA blend”.

When free amino acids are added, some panels count them toward the protein figure. If protein per serve looks unusually high for the stated source, check the ingredient list for added glycine, taurine, creatine or free-form amino acids. This practice, sometimes called amino spiking, works because the standard protein test measures nitrogen, and these cheap additions register as protein without being intact protein. Rules on what can be counted differ by country.

Everything else in the scoop

• Carbohydrate and sugars: mostly lactose in whey concentrate; low in isolate; varies with fibre in plant powders.
• Sweeteners: sucralose, acesulfame potassium and stevia are common. “Natural” or “unflavoured” tubs may still contain one; the ingredient list settles it.
• Thickeners and emulsifiers: xanthan gum, guar gum, soy or sunflower lecithin. They give texture and add non-protein weight.
• Added enzymes: lactase or protease are a formulation choice, not a quality grade.
• Added extras: creatine, caffeine, vitamins or collagen are separate decisions and change the value maths. For creatine specifically, see this guide to reading a creatine monohydrate label.
• Allergen statement: dairy powders declare milk; many are made on lines that also handle soy, egg, nuts or gluten.

Working out value: cost per 100 g of protein

1. Find the tub weight in grams and its price.
2. Divide protein per serve by serving size to get the protein fraction (for example, 25 ÷ 30 = 0.83).
3. Multiply the tub weight by that fraction to get total protein (2,000 g × 0.83 = 1,660 g).
4. Divide the price by total protein and multiply by 100 to get the cost per 100 g of protein.

A worked example with made-up numbers, not real prices at the time of writing (October 2026); prices change and differ by country, so use the figures on the tubs in front of you.

Hypothetical tub	Weight	Price	Protein per serve ÷ serve	Protein in tub	Cost per 100 g protein
A: whey concentrate	2,000 g	$69	24 g ÷ 32 g = 0.75	1,500 g	$4.60
B: whey isolate	1,000 g	$59	27 g ÷ 30 g = 0.90	900 g	$6.56
C: pea-rice blend	1,000 g	$45	21 g ÷ 28 g = 0.75	750 g	$6.00
D: “lean” flavoured blend	1,500 g	$79	20 g ÷ 40 g = 0.50	750 g	$10.53

Tub D is the point of the exercise: a big tub at a mid-range price, and the most expensive protein in the table by far, because half of every scoop is something else. Nothing on its front label needs to be false for that to happen.

Checklist before you buy

1. Work out the protein percentage. Anything under about 70 per cent is carrying a lot of non-protein weight.
2. Check the first ingredient matches the protein type on the front.
3. Scan for added free amino acids that may inflate the protein figure.
4. Work out cost per 100 g of protein for every tub you are comparing.
5. Read the allergen statement, sweeteners and any added extras.
6. Look for a batch number, a best-before date comfortably beyond when you will finish the tub, and an independent testing seal if it matters to you. This guide to supplement certification seals explains what each programme checks.
7. If you have a health condition or take medicines, talk to your doctor, pharmacist or an accredited dietitian first.

Who each type tends to suit

• Lowest cost per gram of protein, no dairy concerns: whey concentrate is often the starting point.
• Bothered by lactose: isolate is usually lower in lactose than concentrate, though not necessarily lactose-free; plant powders contain none.
• Dairy-free or vegan: soy isolate or a pea-rice blend.
• Want a thick texture: casein or milk protein.
• Want food rather than protein alone: hemp and seed powders bring fibre and fat.

Protein powder is not the only option. Some people prefer protein from everyday foods, or a bar; this guide to reading protein bar labels uses similar checks. Nutritionally complete drinks are a different product again, covered in this guide to supplement drinks.

Common mistakes

• Comparing grams per serve across different scoop sizes. Always compare protein percentage.
• Judging value by tub price. Cost per 100 g of protein is the fair measure.
• Assuming “isolate” on the front means isolate in the tub. The ingredient order tells you.
• Missing amino spiking. Added glycine or taurine can make the protein figure look better than it is.
• Taking a seal as proof of benefit. Testing programmes check contamination and label accuracy, not effects.
• Using powder without asking, if you have kidney disease. Protein intake is something to plan with your doctor or dietitian.
• Buying overseas without checking local rules. Labelling differs by country; this guide to buying supplements internationally explains what to look for.

Related guide: Lactose-Free Protein Powder: How to Buy Smart and Stay Safe.

Related guide: Does Protein Powder Expire? The Simple, Safe Storage Guide.

Related guide: Clear Protein Powder: How to Choose It Without Wasting Money.

Sources this guide draws on: National Institutes of Health Office of Dietary Supplements, Dietary Supplements for Exercise and Athletic Performance fact sheet for health professionals; U.S. Food and Drug Administration Dietary Supplement Labeling Guide; Food Standards Australia New Zealand Food Standards Code nutrition information requirements. Protein percentages by type are typical labelled ranges observed across products on sale.

Frequently asked questions

What is the difference between whey isolate and whey concentrate?

Isolate is filtered further to remove most of the lactose and fat, so it is usually 90 per cent protein or more. Concentrate is less processed, contains more lactose and fat, and is usually cheaper per gram of protein.

Is plant protein as good as whey on the label?

Soy isolate is comparable to whey isolate in protein percentage, and pea-rice blends combine two proteins that complement each other’s amino acids. Whey is higher in leucine. Compare protein percentage and cost per 100 g, and check fibre and sodium.

How do I know if a protein powder is amino spiked?

Check the ingredient list for added glycine, taurine, creatine or free-form amino acids, especially if the protein figure looks high for the source. Independent testing seals that check label accuracy add confidence.

Is whey isolate lactose-free?

Not necessarily. It is usually very low in lactose, which many people with lactose sensitivity find easier, but only products labelled lactose-free meet that standard. People with a milk allergy should avoid dairy proteins altogether and talk to their doctor.

What is a good protein percentage for a powder?

Whey isolate and soy isolate usually reach about 90 per cent, and most good concentrates and plant blends sit around 70 to 85 per cent. Much lower than about 70 per cent means a large share of each scoop is something other than protein.

The bottom line

The front of a protein tub tells you what the brand wants you to notice; the panel tells you what you are buying. Work out the protein percentage, check the ingredient order, look for spiking, and compare cost per 100 g of protein. For the wider picture on choosing supplements, see the supplements evidence and label guide, and for label basics, how to read a supplement label.

This article is a guide to reading packaging and comparing products. It is general information only and is not medical advice. It makes no claim that protein powder benefits any condition and it recommends no dose. Speak with a qualified healthcare professional before starting any supplement.