10 min - BioSense Team - 2025-01-28
- thyroid
- TSH
- hormones
- endocrinology
Complete Thyroid Panel: Understanding Your Tests
Note: This guide is for educational purposes only and does not replace professional medical advice.
The thyroid regulates metabolism. Dysfunction affects the entire body.
Thyroid Hormones
### TSH (Thyroid Stimulating Hormone) - Normal: 0.4-4.0 mIU/L - Hyperthyroidism: TSH < 0.4 mIU/L - Hypothyroidism: TSH > 4.0 mIU/L - Role: Stimulates T3 and T4 production
### Free T4 (Thyroxine) - Normal: 0.8-1.8 ng/dL (10-23 pmol/L) - Active form: Converted to T3 in tissues - Storage: Hormone reservoir
### Free T3 (Triiodothyronine) - Normal: 2.3-4.2 pg/mL (3.5-6.5 pmol/L) - Active hormone: 3-4 times more potent than T4 - Production: 80% by peripheral conversion
Thyroid Antibodies
### Anti-TPO (Anti-peroxidase) - Normal: < 35 IU/mL - Elevation: Hashimoto's thyroiditis - Monitoring: Evolution to hypothyroidism
### Anti-thyroglobulin - Normal: < 40 IU/mL - Association: Often with anti-TPO - Surveillance: Thyroid cancer (post-surgery)
### TSHR Antibodies (TRAb) - Normal: < 1.5 IU/L - Elevation: Graves' disease - Prognosis: Hyperthyroidism evolution
Symptoms by Dysfunction
### Hypothyroidism - Fatigue, weight gain - Cold intolerance, constipation - Dry skin, hair loss - Bradycardia, depression
### Hyperthyroidism - Weight loss, nervousness - Tachycardia, sweating - Tremors, insomnia - Diarrhea, irritability
Nutritional Factors
### Iodine - Requirements: 150 μg/day - Sources: Iodized salt, seafood - Excess/deficiency: Possible dysfunctions
### Selenium - T4→T3 conversion: Selenium-dependent enzyme - Sources: Brazil nuts, fish - Deficiency: Common in Europe
### Tyrosine - Precursor: Amino acid of thyroid hormones - Sources: Animal proteins, legumes
Related Articles
See also: TSH: Understanding Thresholds, Ferritin, Sleep and Inflammation.
*Information based on Cleveland Clinic and EMA recommendations*