By Teresa Alasio MD
In today’s fast-paced world, stress is a constant companion. Whether it’s work deadlines, family responsibilities, or everyday challenges, our bodies react to stress in a fascinating way: by releasing cortisol. Often called the “stress hormone,” cortisol is crucial for our body’s ability to function, adapt, and survive. But what exactly is cortisol, and how can we use its power to improve our health and well-being?
What Is Cortisol and Where Is It Produced?
Cortisol is a hormone produced by the adrenal glands, which sit atop our kidneys. It belongs to a class of steroid hormones called glucocorticoids and is essential for many bodily functions. Cortisol production is regulated by the hypothalamic-pituitary-adrenal (HPA) axis, a system involving the hypothalamus (in the brain), the pituitary gland, and the adrenal glands. When the body perceives stress—physical, emotional, or psychological—the hypothalamus signals the pituitary gland, which then prompts the adrenal glands to release cortisol. This process helps the body adapt to stress and maintain balance. However, when cortisol levels become dysregulated, it can lead to various health problems.
The Role of Cortisol in the Body
Cortisol is more than just a stress hormone. It performs several vital functions that help keep our bodies in equilibrium. These include regulating metabolism by helping convert fats, proteins, and carbohydrates into energy, which is critical for maintaining stable blood sugar levels and preventing fatigue. Cortisol also controls inflammation, acting as a natural anti-inflammatory that helps the body manage immune responses and reduce swelling. It’s also involved in managing blood pressure, ensuring efficient blood flow, and influencing sleep-wake cycles, as cortisol levels naturally fluctuate throughout the day, impacting our energy, focus, and sleep quality. Finally, cortisol supports the fight-or-flight response by increasing blood sugar in moments of stress, providing quick energy to respond to threats.
What Happens When Cortisol Levels Are Out of Balance?
Like any hormone, cortisol functions best when balanced. Chronic stress, poor lifestyle choices, and irregular sleep can lead to elevated or deficient cortisol levels, both of which have negative consequences.
High cortisol, often a result of a chronic stress response, can cause weight gain, especially in the abdomen, increased anxiety and irritability, high blood pressure, a weakened immune system, difficulty sleeping, brain fog and memory issues, and blood sugar imbalances, which can increase the risk of diabetes. Chronic high cortisol is linked to conditions such as adrenal fatigue, metabolic disorders, and even depression.
On the other hand, low cortisol, sometimes associated with adrenal insufficiency, can result in extreme fatigue and sluggishness, low blood pressure, unexplained weight loss, dizziness or fainting, and salt cravings. Low cortisol levels are often associated with burnout or adrenal fatigue, a condition where the adrenal glands struggle to keep up with the body’s constant stress demands.
The Cortisol Cycle: Timing Your Day for Optimal Health
Cortisol follows a daily rhythm, known as the circadian cortisol cycle. Understanding this natural cycle can help us make better decisions regarding sleep, exercise, and productivity. Cortisol is at its highest upon waking (6-8 AM), helping us feel alert and energized. This is the best time for exercise, goal-setting, and tackling demanding tasks. It begins to dip midday (12-2 PM), which is why many people experience an afternoon slump. A light meal, a short walk, or a power nap can help reset energy levels. In the evening (6-9 PM), cortisol naturally lowers to prepare the body for rest. Relaxing activities like stretching, reading, or meditation can enhance this process. Finally, cortisol is at its lowest during deep sleep (10 PM-4 AM). This is when the body repairs itself, and disruptions, such as screen time before bed, can interfere with proper hormone function. By aligning our daily activities with our cortisol cycle, we can improve our energy, focus, and overall well-being.
Using Cortisol to Your Advantage in Health and Fitness
Because cortisol impacts metabolism, energy, and recovery, understanding how to work with, rather than against, it can enhance exercise and overall health. Exercising in the morning, when cortisol is naturally elevated, helps burn fat more efficiently and kickstart metabolism. Strength training or high-intensity workouts are ideal at this time. If stress levels are high, a lighter yoga or stretching session in the evening can help lower cortisol and improve relaxation. To balance cortisol through lifestyle choices, prioritize sleep, aiming for 7-9 hours of quality sleep per night to keep cortisol rhythms balanced. Eat balanced meals, avoiding excessive sugar and refined carbs, which can spike cortisol, and opting for protein, healthy fats, and fiber-rich foods to support stable energy levels. Practice stress management through activities like deep breathing, meditation, and spending time in nature. Finally, avoid overtraining, as too much high-intensity exercise can spike cortisol, leading to burnout. Balance workouts with rest days and lower-intensity activities like walking or yoga.
Final Thoughts
Cortisol, often misunderstood, is essential for survival, energy, and resilience. When balanced, it supports healthy metabolism, mental clarity, and immune function. However, chronic stress or poor lifestyle habits can disrupt cortisol levels, leading to fatigue, weight gain, and long-term health issues. By understanding and working with our cortisol cycle, we can optimize our energy, exercise routine, and overall well-being. The key is moderation and mindfulness—giving our bodies the rest, fuel, and movement they need to function at their best. So, rather than fearing cortisol, learn to harness its power for a healthier, more vibrant life.
The information presented is for educational purposes only and not as a substitute for medical advice. If you have a specific medical concern, please consult your medical provider.
Dr. Teresa Alasio is the Medical Director and Owner of Intentional Self Aesthetics, located in downtown New Canaan. She lives in New Canaan with her family and prefers to exercise in the morning.
