Myths vs facts: Cortisol and stress

Cortisol is often demonized as the 'stress hormone,' but the reality is more nuanced. Fact: Cortisol is essential for energy metabolism, blood pressure regulation, and immune function. A common myth is that stress always elevates cortisol. In truth, chronic stress often leads to a flattened diurnal rhythm or even hypocortisolism. Another myth: a single saliva test can assess your cortisol status. The truth is that cortisol follows a strong circadian rhythm, requiring multiple time-point measurements (morning, noon, evening) and possibly a dexamethasone suppression test for accurate assessment. Direct-to-consumer (DTC) tests like Hormon VitalCheck claim comprehensive hormone analysis but lack published clinical validation. The genetic contribution to cortisol regulation is polygenic and overshadowed by lifestyle factors (sleep, diet, exercise). Without medical interpretation, DTC results can lead to misinterpretation and unnecessary worry. Bottom line: Cortisol is not an enemy but a finely tuned system. Myths arise from oversimplification and marketing. Evidence-based assessment requires repeated measurements and clinical context.