Soy Protein
A plant-based complete protein containing all nine essential amino acids, studied as a practical option for those with dairy allergies or following a vegan diet. Leucine content is somewhat lower than whey, which may result in a slightly smaller muscle protein synthesis response, but research suggests it is a useful tool for meeting total daily protein targets.
An ingredient with growing research
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Effects reported in research
Helps meet total daily protein intake (research recommends 1.6–2.2 g/kg body weight)
Studies report it may support lean mass maintenance or gains when combined with resistance training
Researched as a means for lactose-intolerant or vegan individuals to reach protein targets
Contains isoflavones; many studies report no adverse effects on male endocrine function at typical intake levels
Dosage & timing
- 20–40 g per serving.
- Combine with dietary protein sources so that total daily protein reaches at least 1.6 g/kg body weight.
- Pairing with other protein sources can complement the amino acid profile.
Cautions
- •Avoid if you have a soy allergy.
- •Isoflavones are phytoestrogens; individuals with hormone-sensitive conditions (e.g., breast cancer, endometriosis) should consult a doctor before use.
- •Those with thyroid disorders or taking thyroid medication should also seek medical advice beforehand.
- •Individuals with impaired kidney function should follow their doctor's guidance on high-protein diets.
- •This supplement is not a medicine and is not intended to diagnose, treat, or prevent any disease.
Supporting research
Last checked: 2026-06-26