Most People Think of Adrenaline — But the Real Work Happens in the Three Zones of the Adrenal Cortex

Added: 2026-06-02

[00:00:00]Adrenals are famous for adrenaline, but that's just the core. The outer cortex has three zones, each making a steroid vital for survival.

[00:00:10]Three zones, three hormones from cholesterol. Glomerulosa, fasciculata, reticularis, all in a thin shell, all within a thin shell.

[00:00:21]Glomerulosa makes aldosterone, controls blood pressure and volume through the kidneys.

[00:00:26]Fasciculata makes cortisol, raises blood sugar, suppresses immunity, mobilizes muscle, shifts fat. Not just stress, total metabolic control.

[00:00:37]Reticularis makes DHEA, converted to androgens and estrogens. In females, the main androgen source. Activates before puberty.

[00:00:47]HPA axis keeps cortisol in check via negative feedback. Chronic stress disrupts it.

[00:00:53]Cortisol peaks before waking, mobilizes glucose, redistributes immune cells, signals your body to shift from sleep to readiness.

[00:01:02]Three zones, pressure, sugar, immunity, sex hormones, daily wakefulness, all run by a tiny shell most people never notice.

[00:01:12]Follow for the next organ. Educational only, not medical advice.