An autoimmune form of hypothyroidism, and the most common cause of low thyroid function in the U.S. — often under-treated by conventional medication alone.
In Hashimoto's, the immune system produces antibodies that attack the thyroid gland, gradually impairing its ability to produce hormone. It is estimated that the large majority of hypothyroidism cases trace back to this autoimmune process.
Symptoms overlap with other forms of thyroid dysfunction: fatigue, weight gain that resists diet and exercise, brain fog, hair thinning, and a persistent sense of being "off."