Does elevated morning cortisol with low DHEA-S indicate a cortisol-dominant HPA-axis?

A pattern of elevated morning cortisol paired with low DHEA-S is a clinically validated biomarker for HPA-axis dysregulation, often referred to as a "cortisol-dominant" output. This hormonal profile represents a shift in adrenal production that favors the catabolic actions of glucocorticoids over the anabolic effects of androgens.

Clinical evidence

Research identifies the cortisol-to-DHEA-S ratio (CDR) as a robust indicator of allostatic load—the cumulative "wear and tear" on the body caused by chronic stress. In studies of chronic stress physiology, individuals frequently exhibit a higher CDR, which correlates with adverse health outcomes across several domains:

• Metabolic Health: High CDR is associated with insulin resistance, central adiposity, and increased cardiovascular risk.
• Mental Health: Elevated ratios are linked to higher rates of depression, anxiety, and cognitive decline, as the neuroprotective effects of DHEA-S are overshadowed by the neurotoxic potential of prolonged cortisol exposure.
• Immune Function: The imbalance promotes a pro-inflammatory state, as the immunosuppressive and anti-inflammatory balance normally provided by these hormones is disrupted.

Mechanistic explanations

The transition to a cortisol-dominant state is driven by sustained activation of the hypothalamic-pituitary-adrenal (HPA) axis. Chronic stressors trigger persistent secretion of adrenocorticotropic hormone (ACTH). While ACTH initially stimulates both cortisol and DHEA-S, prolonged stimulation often leads to a divergent response:

• Enzymatic Shifting: Chronic stress can alter the expression of adrenal enzymes (such as 17,20-lyase), favoring the glucocorticoid pathway.
• Negative Feedback Failure: Impaired negative feedback loops allow morning cortisol to remain elevated (above-optimal) despite high systemic levels.
• Note on "Pregnenolone Steal": While the clinical observation of high cortisol and low DHEA-S is well-supported, the popular "pregnenolone steal" hypothesis—the idea that the body "robs" DHEA precursors to make cortisol—is not supported by current mechanistic evidence. Instead, the shift is governed by complex signaling and selective enzymatic regulation within the adrenal cortex.

Bottom line

A high morning cortisol-to-DHEA-S ratio is a validated marker of chronic stress physiology, reflecting an HPA axis biased toward catabolism and systemic inflammation. This pattern serves as a significant predictor of metabolic and psychological vulnerability.