Re: thyroid - and soy

[Guest guest]

>> read an article that soy interferes with thyroid medicines.

Anyone else heard this. I found an article but that is all it said,

soy interferes with thyroid. Help?<<<

Haven't heard of this specifically, but my gynocologist told me (pre

op) not to use lots of soy products (soy nuts, soy milk, soy

proteins) because it would mess with my estrogen level. So it seems

highly possible that it would impact thyroid medication.

Here is what Dr. Weil wrote (02/2002) in response to a similar

question:

Some foods, especially cruciferous vegetables (cabbage, kale,

Brussels sprouts, broccoli, and cauliflower), contain natural

goitrogens, chemicals that cause the thyroid gland to enlarge by

interfering with thyroid hormone synthesis. Cooking has been reported

to inactivate this effect in Brussels sprouts. Cassava, a starchy

root that is the source of tapioca, can also have this effect. Other

goitrogens include corn, sweet potatoes, lima beans, and soy. Some

practitioners recommend that people with hypothyroidism (an

underactive thyroid gland) avoid these foods, even though most have

not been proved to cause hypothyroidism in humans.

The only food I would caution you about is soy. Excess consumption of

soy can affect thyroid function, but is usually only a problem in

those taking synthroid or other thyroid replacement medication. If

you are on such medication, tell your doctor how much soy you consume

so your dosage can be adjusted, if necessary. You should also know

that if you eat soy foods at the same time that you take thyroid

hormone, they may interfere with its absorption. To be safe, do not

eat soy within three hours of taking your medication. Moderate soy

consumption should not be a problem – that means one serving a day of

whole soy products, such as one cup of soy milk or one half cup of

tofu, soy protein (tempeh), or crispy soy nuts.

Dr. Weil