Thyroid Function Blood Test

Thyroid Hormones (3 Biomarkers)

A gland at the front of your neck called the thyroid makes hormones that aid in regulating your metabolism.

Your thyroid may generate too little or too many thyroid hormones, and either situation can cause crippling symptoms. Lethargy, weight gain, dry skin, and hair are typical symptoms of an underactive thyroid, while nervousness and anxiety are typical signs of an overactive thyroid, as well as weight loss.

Once detected, thyroid disorders can be treated, but even then, it's crucial to keep an eye on your thyroid hormone levels to make sure they stay at their ideal levels.

TSH

The thyroid is a gland located near the base of the neck that regulates several metabolic processes, including substrate turnover, heart function, muscle physiology, and energy expenditure.

Thyroid dysfunction can cause either overproduction of hormones (overactive) or underproduction of hormones (underactive), both of which can lower athletic performance. The pituitary gland produces Thyroid Stimulating Hormone (TSH), which stimulates the thyroid gland to create the thyroid hormones thyroxine (T4) and triiodothyronine (T3).

As part of a neuroendocrine cascade, thyroid hormone synthesis occurs. Thyrotropin releasing hormone (TRH) is released first in the hypothalamus, where it causes the pituitary to release thyroid stimulating hormone (TSH).

To release the hormones T3 and T4, this attaches to thyroid gland cells (thyroxine). Additionally, peripheral tissues convert T4 into T3, the thyroid hormone with greater activity.These hormones are essentially what regulate your body's metabolism.

Negative feedback loops typically maintain a tight balance between all of these levels. Thyroid hormone over- or under-secretion can be a sign of abnormal thyroid function. These disorders frequently have an autoimmune component, which can frequently be detected by looking at your thyroid antibodies in more sophisticated thyroid tests.

Free Thyroxine

One of the two hormones that the thyroid gland produces is thyroxine (T4). It accelerates the rate at which your metabolism functions.

The majority of T4 in the blood is bound to carrier proteins, but this test solely measures free, or unbound, T4, which is active in the body.

Free T3

The more active of the two thyroid hormones made by the thyroid gland is triiodothyronine (T3).

In the blood, the majority of T3 is protein-bound. The amount of T3 that is available to control metabolism and is free, or not bound to protein, is measured by free T3.