During first visits, I often review a lab and hear, "Low cortisol is good, right?" or "High cortisol is bad, isn't it?" Not exactly. Cortisol is not the villain. The problem is chronic activation.
Cortisol is made by your adrenal glands and it is part of a beautifully designed survival system. When a threat appears, adrenaline surges first, then the hypothalamic-pituitary-adrenal axis engages and cortisol takes over the longer phase, maintaining blood pressure, regulating metabolism, and keeping energy available. A short-term spike is protective and can save your life. The catch is that most of us are not running from predators, yet our bodies respond to work demands, financial pressure, poor sleep, inflammation, and emotional strain as if we are. Repeated activation changes the story.
When protective becomes disruptive
When cortisol stays elevated over time, it raises glucose and reduces insulin sensitivity, breaks down muscle, drives visceral fat storage around the abdomen, and increases appetite. The more stress you carry, the hungrier you feel, and the cycle continues. Over time this contributes to high blood pressure, insulin resistance, weight gain, and immune suppression, and it reaches the brain too, impairing the hippocampus and, with it, memory and focus. A great deal of disease is either caused or worsened by stress.
Here is the key. Cortisol is a hormone you want balanced, not chronically high and not inadequately low. Conventional testing tends to catch only the extremes, Cushing's at the high end and Addison's at the low. The subtle, stress-driven dysregulation in between is where most women actually live, and it is where a functional look at cortisol rhythm becomes so useful.
Your energy roller coaster has a cause
Cortisol follows a daily rhythm. In a healthy system it is highest in the early morning to move you from rest into activity, and lowest at night so your body can rest and repair. When it stays elevated at night, recovery suffers, which is why some high performers stall despite more training. The body cannot repair what it never rests. That late-evening second wind that feels productive is often a stress-driven surge, not real energy.
Under chronic stress the rhythm becomes disrupted. Cortisol may run high at night and low in the morning, or swing unpredictably through the day, which is why so many women feel symptoms of both high and low cortisol and describe their energy as a roller coaster. Left uncorrected, the curve can flatten entirely, leaving persistent fatigue, low resilience, and poor recovery. Many women have quietly normalized this. The one who insists she is "fine" while her labs say otherwise is usually not in denial. She has simply adapted to a baseline that was never sustainable.
Women were built with a buffer
The old fight-or-flight model does not fully capture how women respond to stress. Research describes a tend-and-befriend pattern, where women more often reach for connection and verbal processing under stress. That is not weakness. It is regulation. There is real biology behind it. Women produce more oxytocin, the bonding hormone, which buffers the stress response and helps modulate cortisol, and estrogen enhances that signaling. Connection protects us and isolation amplifies stress, and that is biochemical, not just emotional. The hard part is that chronic stress can dismantle the very buffer we were given, reducing oxytocin and gradually removing the tools the body was designed to recover with.
Why "everything feels like too much"
Cortisol does not travel alone. Chronic stress dysregulates neurotransmitters and depletes GABA, the calming messenger that helps your nervous system wind down. Progesterone and its precursor pregnenolone both support GABA, so when stress shifts pregnenolone toward cortisol production, and when progesterone falls in the luteal phase or through perimenopause, that calming buffer thins out on both sides at once. This is why so many women describe a blunted stress response, where what used to roll off now destabilizes them. That is not a character flaw. It is a neurochemical strain from a system running too long without restoration.
The encouraging news is that this is correctable. For some women, restoring cortisol rhythm and rebalancing sex hormones is enough to bring stability back. In more complex cases, targeted neurotransmitter support helps. Because cortisol and insulin are so intertwined, they are best addressed together. Stress recovery is layered, but the body is designed for cycles of activation and restoration, and restoring that rhythm is one of the most important things you can do for your brain, heart, metabolism, and hormones.
This post is drawn from Chapter 9 of my book, Where Faith Meets Medicine, where I walk through cortisol testing, the daily rhythm, and a full plan for adrenal recovery.
