Finals, work deadlines, traffic, moving. So many events we face in our daily lives can be high inducers of stress. Stress can be unpleasant and often gets a bad name, being linked to mental and physical health problems of all kinds. The stress hormone cortisol is often blamed for these negative consequences. But stress hormones such as cortisol exist for a reason, and cortisol helps us in all sorts of surprising and important ways. In short, stress hormones can be good for you! Here are five ways cortisol helps you every day.
1. Helps you wake up, face the day. Each morning, your cortisol levels surge dramatically in the first half hour after waking, helping you to overcome sleepiness and releasing glucose into your bloodstream to give you the energy to face the demands of your day. In fact, studies suggest that on days that you have bigger anticipated demands, you are likely to have a bigger morning cortisol surge in the morning, helping you to face your especially challenging day. Its like a (natural) extra cup of coffee on the days you need it! Your morning cortisol surge (called the cortisol awakening response) can also help you recover from a bad day. In my studies of adolescents and adults, I find that if someone had a lonely or sad day the day before, their stress hormone surge will be bigger the next morning. It seems that your body is trying to give you the energy "boost" you need have a better, more socially engaged day the next day.
2. Dropping across the day to help you sleep. Although your stress hormone levels are high in the morning, they typically drop to low levels at night, to help prepare your body for sleep. On nights that cortisol fails to drop as much as usual, people have more trouble sleeping that night. This provides evidence that a typical, healthy decline in cortisol levels across the day might help you get a good night's rest.
3. Facing stressful events. Your cortisol levels surge at other times throughout the day when you face unexpected stressors or negative emotions. These small increases in cortisol help provide energy, focus your attention on the stressful event, and suppress less immediately essential processes such as digestion, all of which help you better cope with the stressor at hand. Stress-related increases in cortisol can even help you overcome fatigue, at least temporarily, allowing you to forget your tiredness and do what you need to do.
As an example, due to a flight cancellation, my husband and I arrived home exhausted from a trip, only to find our boiler spewing water all over our basement. Suddenly, we had the energy (thanks to a stress response) to throw away soaked belongings that had been accumulating for years, to mop up all the water, and to find the right plumber to install a new water heater. (Our basement has never been cleaner.)
4. Optimizing your cognition. Research has shown that moderate amounts of cortisol are good for our thinking, such as our abilities to attend to information, remember, and solve problems. Both too little cortisol and too much cortisol are problematic for cognition. For the most part, however, our bodies try to help us hit the sweet spot, giving us just enough cortisol and alertness to help us focus and learn in the ways we need to.
How cortisol changes across the day also matters for cognition. Individuals who have cortisol levels that are high in the morning and decline across the day in the expected way tend to have better control over their cognitive processes (known as better "executive functioning").
5. Regulating your immune system. Cortisol helps to regulate your immune system. When cortisol levels are too low, problems of immune system over-activity can arise (e.g. autoimmune disorders). Cortisol, which is a type of "glucocorticoid," also helps to control inflammation, which is why glucocorticoids are in many medications, such as for asthma and rashes.
Of course, cortisol isn't always "the good guy." If you have too much cortisol, too little cortisol, or it doesn't respond to stress, change as it should across the day, or regulate other aspects of biology in the expected ways, it can indeed be costly to health and wellbeing.
We can help to make sure our stress hormones are well-regulated, and working for us rather than against us, by getting proper amounts of sleep, using stress-busters like exercise and meditation to help keep our stress levels in check, and having regular, positive contact with friends and family. Maintaining positive social relationships is one of the best ways to keep your stress hormone levels well-regulated, and helping you in the ways they should be.
It is therefore both important and healthy to understand that stress is expected in daily life, and our built-in biological response to stress is helpful. Stress hormones, including cortisol, can help us to handle our everyday challenges in amazing ways.