Thyroid
TSH
Unit: mIU/LID: T001
What This Test Measures
Thyroid-stimulating hormone; pituitary signal to thyroid
Conventional vs. Functional Optimal Range
Conventional "Normal"
0.5-4.5 mIU/LYour doctor says you're "fine" anywhere in this range
Functional Optimal
1.0-2.0 mIU/LThis is where you actually feel great
The gap between these ranges is why you feel terrible with "normal" labs. Conventional medicine waits for disease. Functional medicine optimizes for health.
Gabriel's Take
Your TSH of 3.8 is "normal" by conventional standards, but functionally it suggests your thyroid is working harder than optimal. Most people feel best with TSH 1.0-2.0. Above 2.5 often correlates with fatigue, weight gain, and brain fog even when doctors say you're "fine."
When This Test Is High
Primary hypothyroidism, Hashimoto's, pituitary tumor
When This Test Is Low
Hyperthyroidism, Graves' disease, overmedication
Related Conditions
Fatigue, weight gain, cold intolerance, depression
Recommended Follow-Up
Recheck in 6-8 weeks with full thyroid panel including antibodies