Thyroid patients are very focused on anti-TPO, but anti-TG is also important. If we have high levels, it can mean, that there is some damage to our thyroid. And did you know that 10% of Hashimotos patients don’t even have anti-TPO, only anti-TG?
Thyroglobulin is a large molecule. It’s involved in the manufacturing and storage of thyroid hormones. It’s supposed to stay primarily INSIDE the thyroid. But it’s normal to have tiny amounts floating around in the circulation. We can get anti bodies to the thyro-globulin when levels become high, anti-TG.
Thyroglobulin can release into the circulation in various ways:
When the thyroid is being destroyed.
When the thyroglobulin contains very little iodine.
When they suddenly contain much more iodine (when one has been iodine deficient and suddenly increase iodine intake by a lot).
And lastly, in thyroid cancer, TG can get released in connection with the synthetization of hormone.
One did think, that anti-TG was pretty harmless in terms of damage to the thyroid. But this is changing. It looks to be potentially more harmful than anti-TPO.
It’s important to test anti-TG when one suspects AITD, because some people have only elevated levels of anti-TG, and not anti-TPO. I don’t think many doctors are aware of that fact.