Foods that reduce metabolic rate ?!?

Being a general fan of cole vegetables like cabbage and broccoli, I was surprised at what I read in this article on hypothyroidism.

http://www.drhoffman.com/page.cfm/607

Eating uncooked broccoli and cabbage apparently can block thyroid activity by inhibiting iodine uptake, and as a result depress metabolic rate.  The author contends that certain vegetables should be eaten cooked.

Goodbye cole slaw and broccoli salad?

interesting someone last week just told me that his doctor said bananas slow down your metabolism....I had never heard that before!

It's like everything else.  Moderate amounts of any given food is not going to do any damage.   Excessive amounts of one food to the exclusion of others and you're going to hit problems.   Enjoy your colelslaw etc., but enjoy steamed broccoli another day.

I can almost guarantee you that if I search the web enough, I can find another doctor's or research article that says the opposite.

There doesn't seem to be much debate about whether raw cruciferous vegetables induce hypothyroidism, but to what degree they do it is not made clear.  Here's another quote, taken from nahanniriverherbs.com:

"...all the foods that contain substances called goitrogens (raw cruciferous vegetables like cauliflower, broccoli, cabbage, and brussels sprouts) as they can interfere with thyroid function and cause a thyroid problem. Cooking inactivates the thyroid-blocking components. The anti-thyroid components contained in these foods are enhanced by juicing and can induce a mild hypothyroid state when used in this manner."

What I'd like to see is some comment on the size of the effect in calories per day from the nutrition literature.  The authors of what I've read so far do not seem to have any axes to grind. They're not doing this to sell supplements or colon cleansers.  Judging from the language they use there is a real physiological effect, which could measurably increase the thyroid inhibition caused by dieting.  But so far all I've found are broad generalities.

Last night I did the healthy thing and braised my cabbage....

Edit: here's a more legitimate link.  http://www.whfoods.com/genpage.php?tname=geor ge&dbid=47

In summary: limit the intake of raw goitrogenics (the cruciferous vegetables AND soy (including tofu)) to 3-4 cups per week.

Original Post by coach_k:

I can almost guarantee you that if I search the web enough, I can find another doctor's or research article that says the opposite.

This is generally true but science works on "balance of the evidence to support a theory" rather than one or two unreplicatable studies. The real question is whether the affect, if true, is substantial or not. I am guessing that it isn't that serious unless maybe you eat a ton of raw cruciferous vegitables each day. Generally, we tend to find these hormonal effects of foods to be rather self-limiting and not something you should worry to much about if you have a good diet.