Flax Seed suppresses thyroid function???

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Flax Seed suppresses thyroid function???

Postby r-marie » Fri Jul 18, 2008 8:49 am

I think nearly everyone on this forum - including most vegetarians in general - regularly consume ground flax seed to get their essential fatty acids (omega 3). The other day a friend said "did you know flaxseed suppresses the thyroid?" I said I didn't and promptly did a google search.
I got conflicting results.

Since we already know of the good benefits of flax seeds, I'm going to list one of the opposing views:

Excerpt:
"Flaxseed is a cyanogenic goitrogen, which means it contains a substance that converts to thiocyanate in the body. Thiocyanate effectively blocks iodine concentration by the thyroid gland and thus causes thyroid dysfunction.
Flax is also a rich source of lignan, a phytochemical which converts after digestion into a phytoestrogen-like substance. Phytoestrogens are known to suppress thyroid function."
http://www.healthboards.com/boards/show ... 26&page=15

I don't know if this is fact or myth. I AM concerned because I am borderline hypothyroid.

I found nothing on MdD's site in reference to this.

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Re: Flax Seed suppresses thyroid function???

Postby dlb » Fri Jul 18, 2008 11:48 am

r-marie wrote:I think nearly everyone on this forum - including most vegetarians in general - regularly consume ground flax seed to get their essential fatty acids (omega 3).


I don't! It would seem to me from Jeff's previous posts that this is not necessary. Eating good whole plant foods should cover the bases.

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Postby CraftyeLadye » Fri Jul 18, 2008 1:57 pm

I don't consume flax seed at all, have never been told it was necessary.
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Flax seed a pretty good idea

Postby SactoBob » Fri Jul 18, 2008 2:03 pm

I am taking a tbsp of ground flaxseed with my oatmeal in the morning on Jeff's recommendations. I have really noticed a difference in my hair, nails, and skin since I did this. It helps maintain a good ration of omega 3 to omega 6. I am not really up on the science of this, but Jeff's recommendation and my experience is enough to think it is a good idea.
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Postby Karen in FL » Sat Jul 19, 2008 12:18 pm

I'm looking forward to Jeff's reply. I also put 1 Tb flax seed in my morning smoothie.

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Postby HealthFreak » Sun Jul 20, 2008 7:34 pm

Karen in FL wrote:I'm looking forward to Jeff's reply. I also put 1 Tb flax seed in my morning smoothie.

Karen


I am very interested in Jeff's opinion on this topic as well. 30 years ago soy was the new super food. Today flax is the new miracle food. I eat flax or take an algae based DHA pill almost every day.
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Postby Karen in FL » Sun Jul 20, 2008 8:58 pm

HealthFreak wrote:
I am very interested in Jeff's opinion on this topic as well. 30 years ago soy was the new super food. Today flax is the new miracle food. I eat flax or take an algae based DHA pill almost every day.


I do the same. I just had blood work done and the first thyroid test - TSH - concerned the doctor (7.19 H possible hypothyroid) so he re-tested. The next two tests (T-4 free, T-4 thyroxine) came out fine. He wants to re-test in 6 months. If flax is affecting this I want to know.



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flax seed and thyroid

Postby finnmiller » Sun Jul 20, 2008 9:37 pm

I am very interested in a response to this question about thyroid function and flax seed. I do have a hypothyroid condition and have been taking levothyroxine for about two years. I also have high cholestrol, which is why I started taking flax seed about two months ago.

Thanks for any infomation you can provide.
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Re: Flax Seed suppresses thyroid function???

Postby JeffN » Sun Jul 20, 2008 10:07 pm

Many plants contain naturally occurring toxins and while it is true that flaxseeds contain tiny amounts of cyanide-containing substances, this has not been shown to be a problem. The concern arises from the writings in a popular book or two and has not been confirmed in any published studies that I know of.

If you think it is a concern, heating the flaxseeds has been shown to eliminate any detectable amounts of this chemical

So, while it may be theoretically possible that eating huge amounts of raw or unprocessed flaxseeds or flaxseed meal could potentially pose a problem, I am not recommending anyone consume anywhere near that amount and I know of no evidence supporting the concern.

If someone knows of any published peer reviewed data on this, I would be glad to review it.

Enjoy your TB of flaxseeds.

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Postby r-marie » Mon Jul 21, 2008 5:50 am

Jeff, thank you very much for this additional info.

When I did my searches I came across an Indian site (I didn't save the link). It said that in India most flax seed is roasted before grinding. If heat deactivates the toxin, then I would think that's the way to go....unless roasting it also diminishes the good benefits. What do you think?

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Postby JeffN » Mon Jul 21, 2008 5:57 am

r-marie wrote:Jeff, thank you very much for this additional info.

When I did my searches I came across an Indian site (I didn't save the link). It said that in India most flax seed is roasted before grinding. If heat deactivates the toxin, then I would think that's the way to go....unless roasting it also diminishes the good benefits. What do you think?

r-marie


Unless you can show me some reliable information that this is an issue or a serious concern for the amount I recommend, then I think it is not an issue at all or something to worry about.

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Postby bob2200 » Wed Jul 22, 2009 11:38 am

I have replied to this thread because Dr. William Harris of Hawaii, in the July 2009 monthly Vegetarian Society of Hawaii presentation ( http://www.vsh.org/videos.htm ), claims that less than a tablespoon/day of ground flaxseed caused him harm. Dr. McDougall has said he doesn't recommend flaxseed for most people. I use about a tablespoon/day of ground flaxseed with my cereal in the morning and now have a concern.
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Postby Clary » Wed Jul 22, 2009 12:03 pm

bob2200 wrote: Dr. McDougall has said he doesn't recommend flaxseed for most people.
Will you reference where he says that, please?

I remember someone posting here on the board that flaxseed is served daily at the meals at the live-in programs. I wonder if they are suggested only for certain people who are attending, or ????

Thanks, Clary
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Postby JeffN » Wed Jul 22, 2009 12:31 pm

Clary wrote:
bob2200 wrote: Dr. McDougall has said he doesn't recommend flaxseed for most people.
Will you reference where he says that, please?

I remember someone posting here on the board that flaxseed is served daily at the meals at the live-in programs. I wonder if they are suggested only for certain people who are attending, or ????

Thanks, Clary


Flaxseeds are available at the program and are usually out every morning at the breakfast buffet.

Some people are specifically instructed to include them and some are specifically told to avoid them. Every one is there for different reasons.

Remember, omega 3s exist in all plant food and flax seeds are not required if someone wanted to avoid them and in the amounts allowed, would not cause any problem for most anyone. This is covered in a few other threads.

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Postby bob2200 » Wed Jul 22, 2009 2:13 pm

Clary wrote:
bob2200 wrote: Dr. McDougall has said he doesn't recommend flaxseed for most people.
Will you reference where he says that, please?
It was in an e-mail in response to my e-mail today. I too remember the flax seeds on the breakfast food table at the live-in program. As I recall, they were not ground up (but it was 2 years ago).
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