Your immune system normally protects your body from harmful substances. Sometimes, however, it mistakenly reacts against healthy tissue. This is what happens in autoimmune thyroid disease.

TPO antibodies are one sign of this immune response.

Hashimoto’s Is a Major Cause

Hashimoto’s thyroiditis is a common autoimmune thyroid condition associated with elevated TPO antibodies. The immune system gradually targets the thyroid, which may eventually interfere with thyroid hormone production.

Graves’ Can Also Produce TPO Antibodies

Graves’ disease is another autoimmune thyroid disorder. Although different antibodies are particularly important in Graves’ disease, TPO antibodies can also be elevated.

Thyroiditis Can Affect Antibody Results

Inflammatory thyroid conditions can temporarily disrupt thyroid function. Postpartum thyroiditis is one example. It can develop after pregnancy and may involve changing thyroid hormone levels.

Positive Does Not Always Mean Abnormal Thyroid Hormones

One important point is that antibody status and thyroid function are not the same thing. A person can have elevated TPO antibodies while thyroid hormone levels remain normal.

This is why healthcare professionals may order TSH and free T4 tests and interpret them together with symptoms and medical history.

There is no single food, supplement, or lifestyle change that can be assumed to be the cause of every elevated TPO result. Autoimmune thyroid conditions are complex and can involve genetic and environmental influences.

If your TPO antibodies are high, use the result as a reason to understand your thyroid health rather than as a diagnosis by itself.