Stress and Blood Sugar

Elevated cortisol reduces TSH release and lowers T4-to-T3 conversion. The liver normally converts about 60% of the body’s thyroid hormone, and insulin resistance can impair that conversion. Chronic stress impairs thyroid function through cortisol and resource-conservation mechanisms. Blood sugar crashes can trigger cortisol spikes that reduce TSH, increase reverse T3, and reduce T4-to-T3 conversion. Chronic stress can increase thyroid-binding globulin and reduce free active hormone availability. Stress increases deiodinase type 3 activity and promotes reverse T3 production. Insulin resistance is presented as the most important habit-related blocker of thyroid healing because it reduces T4-to-T3 conversion.