Figure 3.

Illustration of the predicted (and non-linear) TSH, T4, and T3 levels prior to initiating any therapy for hypothyroidism in individuals with RTFs varying between 0% (athyreotic) up to 50% RTF (hemi-thyroidectomized). Notably, as RTF increases from about 1–10%, TSH levels fall by ~80%, while T4 levels increase by ~163% and T3 levels increase by ~79%. Similarly, T4 increases by ~30%, T3 by 20% and TSH falls about 58% as RTF increases from 10 to 30%. TSH levels shown in green, T4 levels shown in red, and T3 levels shown in blue.