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[C] The following conclusions are supported by limited evidence or expert opinion:
Results from a systematic literature review and two randomized controlled trials have found that in euthyroid, iodine-repleted healthy adults, isoflavones (from isolated soy protein or pure isoflavones) do not appear to have adverse effects on thyroid function.
In individuals with hypothyroidism, thyroid function should be reassessed when there is a substantial increase or decrease in soy intake.
Two