Soy Interactions

1 documented interaction — 1 warning, 0 beneficial pairs.

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Interaction warnings

Soy + levothyroxine

moderate

Soy protein and isoflavones can bind to levothyroxine in the gut and reduce its absorption, sometimes increasing dose requirements in hypothyroid patients. Case reports and systematic reviews describe rising TSH and unstable thyroid levels in patients consuming soy products close to their dose.

Related ingredients

Ingredients commonly checked alongside Soy.

Levothyroxine(1)
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