Does Soy foods Affect Bovine Thyroid Extract?

Amount or timing may matter

The short answer

Soy interferes with thyroid hormone absorption and utilization, reducing the effectiveness of bovine thyroid extract.

How to arrange timing

Separate bovine thyroid supplements from soy products by at least 4 hours.

Reference

Reference noted for this food and supplement combination: Fitzpatrick, Environ Health Perspect 2000

Important context

The effect can also change with food amount, supplement dose, product formulation, health conditions, and medication use. Ask a doctor or pharmacist first if you take medication, are pregnant or breastfeeding, or have a chronic condition.