Protein

Protein Spiking.

Protein spiking is the label risk that a nitrogen-based protein number looks stronger than the intact protein source behind it.

See it in the glossary ->
CleanLabel verdict

A high protein number still needs a source check.

Protein testing often starts with nitrogen. That is useful, but it can miss the difference between intact protein and added nitrogen-rich compounds unless the formula and amino acid profile are read together.

What it does

Spiking can happen when amino acids or other nitrogen-containing ingredients lift the measured protein result without supplying the same full protein quality as a complete source.

Where it shows up

  • Protein powders and mass gainers
  • Bars and shakes with amino blends
  • Supplements with proprietary blends
  • Products listing glycine, taurine, creatine, or glutamine near protein claims

Label cue

Look for a named protein source first, then scan for free amino acids, creatine, taurine, glycine, and proprietary blends. A transparent amino acid profile is stronger than a loud grams claim.

The catch

Added amino acids are not automatically suspicious. The issue is disclosure and context. A sports formula can include them honestly, but the headline protein number should not do all the trust work.

Source notes

Where the definition comes from.

  • eCFR describes US nutrition labelling rules, including protein calculation from nitrogen in 21 CFR 101.9.
  • FAO explains why protein quality depends on digestible indispensable amino acids, not grams alone.

Back-panel action

If a protein product lists amino acids or a proprietary blend, look for a full amino acid profile and a named primary protein source. If neither is present, treat the front number as incomplete.