SupplementDuel

Soy Protein Isolate

Protein

Complete plant protein with all 9 EAAs. Equivalent muscle-building to whey in older adults; mild cardio-protective effects from isoflavones.

vegancomplete-proteinheart-healthy
Typical dose
25–40 g per serving
Evidence
Moderate (some RCTs)
Onset time
Acute: 45–75 min
Half-life
—
Forms
Powder
Source
plant
Best taken with
water or plant milk
Best time of day
post-workout
Bioavailability
4/5
Safety rating
4/5
Price per serving
$0.60
Vegan / GF / 3rd-party
✓ / ✓ / ✓
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Vetted brands, third-party testing, ships worldwide.

Common uses

  • • Vegan muscle gain
  • • Heart health
  • • Menopause support

Effect profile

Strength
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Energy
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Mood
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Sleep
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Immunity
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Recovery
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Longevity
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Common side effects

  • • Mild estrogen-mimicking (debated, minor)

Avoid if

  • • Soy allergy
  • • Hormone-sensitive cancers (consult MD)

Drug interactions

  • • Thyroid meds (levothyroxine)

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Medical disclaimer

SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements.