Almost everyone chooses their protein by the price on the tub, and the price on the tub is the least informative figure on the label. Here are the four real decisions, in the order in which they matter.
1. Cost per gram of protein, not per tub
It is the only honest comparison and it takes ten seconds: divide the price by the total grams of protein in the container. The total is servings per container × grams of protein per serving, and both figures are on the panel.
Two tubs at the same price can hold twice as much protein one as the other, because the weight of the container includes cocoa, flavourings, thickeners and sugar. The scale weighs the powder; you are paying for the protein.
2. Concentrate, isolate or plant
The difference between the first two is how far the whey has been filtered:
- Concentrate. Less filtered, so it carries a little more fat and lactose and a little less protein per gram of powder. It is the cheapest and, if lactose gives you no trouble, a perfectly reasonable choice.
- Isolate. More filtered: more protein per gram and very little lactose. It costs more. It makes sense if concentrate does not sit well with you, or if you count macros precisely.
- Plant. Pea, fava, rice or blends. The reason to choose it is not that it is «better»: it is that it carries no dairy. The essential amino acid profile should be complete, and blends manage that better than a single source.
For almost everyone, the practical difference between the three is small next to reaching the day's total protein, which is what actually moves the needle.
3. The two label tricks
The blend with no amounts
If the label lists a «proprietary blend» of eight ingredients with a single figure at the end, you cannot know how much of each there is. That is exactly why it is presented that way. The rule is simple: if you cannot compare two products with what the label says, the label is doing its job and you cannot do yours.
Padding with free amino acids
The declared protein content is, in practice, calculated from nitrogen. Cheap amino acids such as glycine or taurine contribute nitrogen without contributing a complete protein, so adding them raises the figure on the panel without raising what is useful to the muscle.
How to spot it: read the ingredient list. If free amino acids appear before or just after the protein source, and the product is conspicuously cheap per gram, be suspicious. An honest protein starts its list with the protein.
4. What should not weigh on the decision
- The flavour in the photo. It changes between batches and says nothing about the contents.
- «Sugar free». It usually means sweetened with something else. Legitimate, but not a quality signal.
- The promises on the tub. A food supplement goes through no prior authorisation before being sold, so what the tub promises has been validated by nobody. It is worked through in which supplements have evidence and which do not.
The thirty-second check
- Grams of protein per serving ÷ grams of powder per serving. Above 0.7 is a dense product; below 0.6, you are buying a fair amount of filler.
- Price ÷ grams of protein in the container. That is the number that compares.
- First line of the ingredient list: is it the protein?
- Is there a «proprietary blend» with no amounts? If there is, next product.
That rules out most of the market without reading a single review. The ones in this shop declare grams per serving and the full ingredient list on the product page, which is what you need to do this arithmetic.
Where each figure comes from
- The rules for the nutrition facts panel, the ingredient list in order of weight and the regime for food supplements —with no authorisation prior to sale— are published by the federal food and drug authority.
- Calculating protein from nitrogen is the analytical method set out in the labelling regulation itself.
United States Government agencies publish in the open and their works are not subject to copyright under 17 U.S.C. § 105. Every figure can be checked one by one; the writing of this article is our own work.
This is a summary. The split of protein across meals, the tables of content by food and how it fits into the rest of the day are worked through in full. It is in the Codex of the Table, a 78-page PDF in Spanish, English and French.
Published by VILLUMINATIONS. This text is informational and does not replace the care of a licensed health professional.