Thyroid hormones

Definition

Thyroid hormones are chemical substances produced by the thyroid gland that regulate metabolism, energy generation, and overall growth and development. The primary thyroid hormones are thyroxine (T4) and triiodothyronine (T3).

5 Must Know Facts For Your Next Test

1. Thyroid hormones influence the basal metabolic rate, affecting how quickly the body uses energy.
2. Iodine is essential for the production of thyroid hormones; a deficiency can lead to hypothyroidism.
3. Hyperthyroidism and hypothyroidism are conditions resulting from an imbalance of thyroid hormones.
4. Dietary selenium supports the conversion of T4 to the more active T3 hormone.
5. Protein intake is crucial for maintaining healthy levels of thyroid hormones.

Review Questions

• What role does iodine play in thyroid hormone production?
• How do thyroid hormones affect basal metabolic rate?
• Name one nutrient besides iodine that supports thyroid hormone function.

Related terms

Hypothyroidism:

a condition where the thyroid gland is underactive and produces insufficient amounts of thyroid hormones

Hyperthyroidism:

a condition where the thyroid gland is overactive and produces excessive amounts of thyroid hormones

Basal Metabolic Rate (BMR): the rate at which your body uses energy while at rest to maintain vital functions such as breathing and keeping warm