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Difference between Thyroglobulin Antibody and Thyroid Peroxidase Antibodies

I have Hashimotos and have gone gluten free to see if it makes any difference to my antibody levels but I still don't understand the difference between TPO Ab and TG Ab. Previous results:

TG Ab 589.200 IU/mL Range (0 -115)

TPO Ab 295.7 IU/mL Range (0.00 -34)

Latest results:

TG Ab 590.0 IU/mL Range (0-115)

TPO Ab 61.2 IU/mL Range (0-34)

So my TPO Ab is way down but my TG Ab is still very high.

I have looked everywhere on line to try and find out what this means. I have been told that it is the TPO Ab which is significant (in which case it seems that my going gluten free has helped) but surely the TG Ab level must mean something.

I have been gluten free for 4 months and don't feel any better and neither have I lost any weight. I should add that I don't eat processed food so I don't buy gluten free products unless they are naturally gluten free.

If anyone can explain the difference between these two antibodies and what these results might mean, I would be very grateful. Thanks.

On 125 mcg of Thyroxine my other levels are all within range and have not really changed.

7 Replies


If you have TPOab and/or TGab positive antibodies you are positive for autoimmune thyroiditis (Hashimoto's). It can take years of being gluten-free to help reduce thyroid antibodies.

If you Google "Thyroid peroxidase antibodies" and "Thyroglobulin antibodies" there should be explanations of the differences.


Many thanks for this. I have googled and googled though and cannot come up with clear distinctions. I do know that I have Hashimoto's. I'm trying to monitor the level of antibodies and have got the impression that TG Ab level doesn't matter, whereas the TPO does



Some people are positive for TgAb and negative for TPOab so TgAb does matter.

I don't have a thyroid but I'm still tested for Thyrogobulin and TgAb annually as thyroglobulin in my blood will indicate the presence of thyroid cells in my body which might be cancerous.


It's the TPO antibodies that react to gluten. Yours show a seriously impressive drop in just 4 months

TG antibodies seem to respond to how low TSH is generally

They can also be high for other reasons


What were you actual TSH, FT4 and FT3 results?

What about vitamin D, folate, B12 and ferritin levels


Thanks both. My TSH (0.01 ref 0.27-4.2) is always very low and is not relevant in my case as the pituitary gland never sends signals to stimulate the TSH regardless of the levels in the body, which was why it took so long for me to get a diagnosis in the first place.

Free thyroxine 20.2 pmo/L Ref range: 12.0 -22.0

Total T4 89 nmol/L Ref range 59-154

Free T3 4.3 pmol/L Ref range 3.1-6.8

I was tested not long ago for Vit D, B vits, ferratin etc and all seemed ok. I take supplements which cover Vitamins D and various B vits.

Still confused about the difference in these antibodies though. I had already looked at the article you mentioned Clutter but it doesn't explain the difference between TG Ab and TPO Ab.

The TG abs only seem to be mentioned in relation to cancer.

Anyway it looks as thought I will have to continue with the gluten free approach as there is such an amazing drop in the TPO abs. Was rather hoping that I could go back to having gluten. What a shame it has to be all or nothing!


Dr Brad Shook has created a great video explaining what Thyroglobulin and Thyroid Peroxidase are and their antibodies. Thyroglobulin is like a taxi cab which transports thyroid hormone around your body and thyroid peroxidase helps produce thyroid hormone.


Thanks so much. This is really helpful. Wish this guy was my doctor!


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