Table 1. Thyroid profile before (Day 1) and after (Day 4) 3 days of T4 supplementation (mean ± SD).

	Day 1	Day 4	P value
T3 (ng/dl)	111±15	109±12	0.68
TSH (µU/ml)	1.82±0.95	0.87±0.35	0.005
T4 (µg/dl)	7.1±1.0	10.0±0.7	0.003
Free T4 (ng/dl)	1.18±0.13	1.56±0.13	<0.001
Thyroid binding capacity (µg/dl)	17.0±3.8	17.2±3.7	0.57