Normal thyroxine (T4) levels vary depending on age, as indicated by reference ranges for total thyroxine (TT4) from emedicine.medscape.com.
Here's a breakdown of normal ranges:
| Age Group | Total Thyroxine (TT4) mcg/dL | Total Thyroxine (TT4) nmol/L |
|---|---|---|
| Newborns (up to 14 days) | 11.8 - 22.6 | 152 - 292 |
| Babies and older children | 6.4 - 13.3 | 83 - 172 |
| Adults | 5.4 - 11.5 | 57 - 148 |
Understanding Thyroxine Levels
- Thyroxine (T4) is a hormone produced by the thyroid gland.
- It plays a crucial role in regulating metabolism, growth, and development.
- Thyroxine levels are measured through blood tests.
- Reference ranges are guidelines, and slight variations can occur. It's always best to consult with a healthcare professional for personalized advice.
Why Different Ranges?
The differences in normal ranges between age groups reflect the varying metabolic needs throughout life. Newborns, with their rapid development, require higher levels compared to adults.
What if my levels are outside the range?
Abnormal thyroxine levels can indicate an underactive (hypothyroidism) or overactive (hyperthyroidism) thyroid. Your healthcare provider can interpret your results in the context of your overall health.
