Glossary · Protein Powders
Amino Spiking
Amino (or protein) spiking is adding free amino acids like glycine and taurine, or non-protein nitrogen, so a label's protein figure reads higher than the intact, complete protein actually justifies — standard nitrogen tests count them all as "protein." It was a documented industry problem, and the defenses are practical: prefer brands that publish a full amino-acid profile or third-party testing, and be skeptical of a suspiciously cheap powder claiming top-tier protein per serving. Where a brand publishes the breakdown, we read it; where it does not, the review says so.
Related terms
Reader favorites
The short list — full rankings live on the rankings page.
Transparent Labs — 100% Grass-Fed Whey Isolate (2 lb / 30 servings)
4.5/5
$59.99
Check priceLMNT — Electrolyte Drink Mix (30-Stick Box)
4.4/5
$45.00
Check priceLegion — Whey+ Isolate (2 lb / 30 servings)
4.4/5
$59.99
Check price
Straight disclosure —Some links on this page are affiliate links — we may earn a commission when you buy through them, at no extra cost to you. It never changes the price you pay, and it never changes a verdict.
4.4/5 average across vetted picks
60 guides published
4 offers vetted
2 reader price checks