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Reviewed by the Scan Dose Research Team and Clinical Advisory Board

Soy Protein

MODERATE EVIDENCEAmino AcidLast updated

SCAN DOSE SUMMARY

Soy protein is the only plant protein with a PDCAAS of 1.0 (matching whey and casein for amino acid quality). Contains isoflavones (see isoflavones.md). A 2010 meta-analysis of 15 studies found soy protein does NOT reduce testosterone or increase estrogen in men — the 'feminization' fear is unfounded. 20-40g/day for muscle protein synthesis. Inferior to whey for acute MPS due to lower leucine content (6.7% vs 11%) but equivalent for long-term muscle building when total protein is adequate. --- *Reviewed by the Dose AI Research Team and Clinical Advisory Board* *Last updated: 2026-04-06*

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BCAAs / EAAs

Quality Testing Intelligence

Based on independent third-party laboratory analysis

Category pass rate: ~75% pass rate for protein content. Heavy metal contamination is the bigger concern — 84% contain detectable arsenic, lead, or cadmium.

Common failures:
Heavy metals (84% of products): Lead, arsenic, cadmium detectable
Amino spiking: Adding cheap amino acids to inflate protein count
Chocolate vs vanilla: Chocolate has 110x more cadmium
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Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:

Not medical advice. Based on published clinical research and systematic reviews.

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