What is TSH?

Most physicians measure thyroid function by testing levels of TSH. TSH stands for Thyroid Stimulating Hormone.

Thyroid Stimulating Hormone is produced by the pituitary gland and stimulates the thyroid gland to produce thyroid hormones. TSH levels are supposed to automatically increase to compensate for low thyroid hormone production. When this happens, TSH levels become abnormally high and indicate a hypothyroid condition.

Unfortunately, most physicians are using an outdated and unnecessarily wide reference range when determining normal TSH levels. You may actually be hypothyroid, but have been told by your physician that your thyroid level is normal.

A normal TSH level is between 0.3 and 2.5 as determined by the American Association of Clinical Endocrinologists. However, most physicians and labs are using a range of 0.30 to 5.00. Therefore your TSH level may increase to what appears to be a very normal looking 3.00, when you may in fact be quite hypothyroid.

Thyroid Antibodies/Hashimotos Thyroiditis

Many hypothyroid conditions are caused by an autoimmune condition that attacks the thyroid gland. There are two major thyroid antibodies, called thyroid peroxidase antibody and anti-thyroglobulin antibody. The presence of these antibodies can indicate an autoimmune condition called Hashimotos Thyroiditis. This condition can be present even if your TSH is normal, and it may affect your need for thyroid hormone.

Image thanks to merck