Q. I have hypothyroidism. I read that soy products can make symptoms worse. I’ve seen other reports that soy is beneficial for women with thyroid disorders.
I take my thyroid medicine first thing 30 minutes before I eat or drink anything. Then I have soy milk and fiber with my cereal.
Can I take thyroid medicine several hours after dinner (with no soy or fiber) just before bedtime? Should I avoid soy? I hope you can clear up my confusion.
A. You are not the only one who is confused. Researchers have found that compounds in soy can inactivate an enzyme important for thyroid function (Environmental Health Perspectives, June 2002, Suppl. 3). Ever since then, scientists have been arguing about the practical importance of this discovery. People low in iodine seem especially susceptible.
We are sending you our Guide to Thyroid Hormones covering several controversial issues, including the use of Armour desiccated thyroid, the balance between T3 and T4 hormones and a list of foods that can affect thyroid function.
It’s smart to avoid fiber when you take your pill, as that might reduce its absorption. In fact, taking it in the evening at least a few hours after you finish eating gives the best results (Clinical Endocrinology, Jan. 2007).
