T4 levels

Definition

T4 levels refer to the concentration of thyroxine, a thyroid hormone, in the blood. Thyroxine plays a crucial role in metabolism, growth, and development across the lifespan.

5 Must Know Facts For Your Next Test

1. T4 is produced by the thyroid gland and regulated by Thyroid Stimulating Hormone (TSH).
2. Normal T4 levels are essential for metabolic rate control and energy production.
3. Both hyperthyroidism (high T4) and hypothyroidism (low T4) can lead to significant health issues.
4. Dietary iodine intake is critical for proper thyroxine production.
5. T4 levels can be influenced by factors such as age, pregnancy, and certain medications.

Review Questions

• What role does T4 play in the body's metabolism?
• How does iodine intake affect T4 levels?
• What are potential health implications of abnormal T4 levels?

Related terms

Thyroid Stimulating Hormone (TSH): A hormone that regulates the production of thyroid hormones including T4.

Hyperthyroidism: A condition characterized by excessive production of thyroid hormones leading to increased metabolism.

Hypothyroidism: A condition characterized by insufficient production of thyroid hormones leading to decreased metabolism.