Thyroid UK
84,272 members99,292 posts

Have I completely destroyed my thyroid?

For the past week or so, I've been feeling a little more lethargic than usual, really depressed due to unexplained weight gain (a ridiculous 18 lbs. in a week) even though I'm an obsessive fitness nut, and experiencing bad constipation issues. I've scoured the net for information regarding these symptoms and found out about hypothyroidism. I don't experience hair loss at all and I think my sensitivity to the cold is just something in my head because I'm paranoid I have the condition, however.

The kicker, and what I'm most concerned about, is the fact that I consumed tofu almost everyday for the past 2 months as my main protein source. I found out that the isoflavones is soy products can affect thyroid functioning and now I'm beating myself up for possibly afflicting myself with this condition singlehandedly. I've since stopped consuming soy products (almost a week now) so is there a chance my thyroid could heal itself in the absence of the isoflavones or do I have to get checked out? I want to go to my GP just to be sure but my mom just thinks that I'm getting worked up for nothing and refuses to have me get my bloodwork done. I'm a 19 year old guy and at a relatively healthy weight. Thanks in advance guys and I hope you're all doing well.

4 Replies

Hello Bax_glynn,

Welcome to our forum and sorry to hear of your possible thyroid problems.

I would definately recommend seeing your GP for blood work.

Also ask to be tested for Vit D, Vit B12, folate and ferritin as deficiencies in these are common in people with thyroid issues.

If there is a thyroid problem and it did not reverse itself, the sooner you get it checked the better. Low thyroid hormones may not produce classic symptoms straight away as your body will compensate for a long time but issues such as the weight gain and lethargy could be clues.

Tofu is made by coagulating soy milk which is controversial re thyroid issues,

with many saying there is not a problem as there is very little available data. However, what is generally recognised is that soy may inhibit thyroid medication and so I believe thyroid hormone conversion.

There is many articles, papers, and discussion on soya discussing the merits and down falls but I consider soy to have quite a powerful effect on the body. Isoflavones that mimic oestrogen can be helpful in stabilising menopause systems but now we hear can cause possible cancer risks. As all endocrine glands are linked it would make sense that ALL could suffer the positive / negative effects of soy.

If you want to take extra protein you could try whey powder in smoothies. I have this because my body seems to react positively to protein and I am not a huge meat eater. You can also use a pea, hemp, sunflower or brown rice protein powder but whey contains most. Moderation is key in everything.

However if you are going to eat soy ... it is best to limit amounts and only consume organic and fermented soy.

As most soy is genetically modified, I just completely avoid but small amounts of gluten free tamari, miso, natto, tempeh should be fine.

I think the best diet is a balanced diet with fresh carbs, proteins, fats, veg & fruit.

Your weight gain ...[.. a ridiculous 18 lbs. in a week ...] .... will most likely be fluid retention down to a sluggish lymphatic system which should recover quickly when thyroid hormones become balanced ..(. If they are the problem..)..

With regard to reversing your condition... I don't know but would guess that if it has been recently bought on by an excess of soy ... then by removing the soy, it must give it good chances. Woman using Isoflavones for menopause symptoms notice changes when adjusting dosages indicating the endocrine glands will respond negatively or positively to dose change...... but this is a guess.

I hope you feel better soon,


Studies Showing Adverse Effects of Isoflavones, 1950-2013

Link detailing study of soy & thyroid function. . ..fairly inconclusive but evidencing change in those with iodine deficiency.

1 like

Bax, if all your symptoms have come on since you started consuming tofu, then I would say there's a good chance that they are due to the tofu. If you had some of them before, then they aren't. If you see what I mean.

However, I would just like to say that consuming tofu as a source of protein is a non-starter, because unfermented soy contains a substance that prevents you absorbing that protein - can't remember the name right now.

The key word there is : unfermented. Soy is only beneficial - and not dangerous - if it is fermented, and tofu isn't.

Just one of the bad effects of unfermented soy - and there are many, many - is that it stops the uptake of iodine by the thyroid gland - what is called the goitrogenic effect. As thyroid hormone is made from iodine and tyrosine, if the gland can't get enough iodine, it can't make enough hormone. So that would cause the symptoms you're complaining about. But, soy doesn't stop there. It then goes on to impede the up-take of thyroid hormone by the cells, where it is used. So, you get a double effect of hypo.

As you've only been consuming it for two months, you say, I doubt the damage is permenant. But it might be a good idea to wait a while before getting tested, because the results would be skewed. Wait a couple of weeks - you'll probably have to wait that long for an appointment, anyway! - until it's all out of your system and your gland has had a chance to start producing hormone again. Then get a check-up to make sure.

But soy really shouldn't be considered a source of protein - that's just the brilliant marketing stratagies used by the soy-growers marketing team! The same people that convinced us to smoke Tobacco! It should only be consumed in small quantities, as a condiment, not a main meal. :)


Dude, soya based products are oestrogenic which is a BAD idea for us guys as far as I know! (look it up). Sorry Im just goin out to work, havent time to go into more detail - but look at my profile & previous replies for problems I have had. If anything sounds familiar, reply or PM me.

Good luck,



Soya has had a lot of bad press, and it's a food to be avoided because of the Goitregens in Soya, if you are Hypothyroid. Previous posters are right, wait a few days, drink plenty of water to

Flush your liver and kidneys, then ask to be tested for Hypothyroidism.

Other foods that contain Goitregens, include millet, the brassicas vegetables, this includes Broccoli, cauliflower and cabbage. These are fine if you cook them

Well, however steaming veg, is much better. Dependent on the severity of the thyroid issue, not everyone can tolerate soya. I can't have it all, I have no thyroid gland, and the mere taste of soya in my mouth sends me hypo.

Lot of confusion around soya in cancer, it's certain types of estrogen, that increase certain estogenic pathways in cancer. Red clover contains phytoestrogens, as does Dong Quai and soya isoflavones. These are fine, I suggest you research Soya, and it's benefits.

I agree it's not for everyone, however it does help a lot of people.


You may also like...