The Science Behind Stress Eating
Two years ago, I was teaching full time, attending graduate school online and training competitively in CrossFit. A typical day would consist of bouts of frustration and tension with my middle school students, followed by a couple of high intensity and highly stressful workouts every afternoon, followed by a strong dose of nighttime anxiety over a paper I was cramming for. At the end of each day, I was exhausted and hungry. I would regularly find myself stuffing my face with frozen yogurt (don’thate, I am lactose intolerant), sweet potato chips, or anything salty or sweet I could get my hands on.
A day full of stress followed by a night full of stress eating, or as we like to call it, “emotional eating”. Does that sound familiar? According to the American Psychological Association, more than one out of three adults claim to have indulged in unhealthy foods or overeaten in the last month due to stress. About 50% of those adults claim to do it on a weekly basis. Stress eating pulls us further away from our health goals and often leaves us feeling discouraged and disappointed in ourselves.
So, how do we prevent it from happening? Unlike most of the fitness’ industries advice, the answer is not as simple as having a little more willpower, going on a Keto diet, signing up for aBeach Body community group, or “relieving stress” through more HIIT training. The solution to emotional eating lies within an understanding of how our bodies respond to stress hormonally and how we can better manage it. Thankfully, for the reader, I am no endocrinologist. As a result, the following discussion on stress hormones may be a bit oversimplified for the sake of readability.
Stress hormones and appetite
When facing a stressful situation, your body releases various hormones that both decrease and increase appetite. It may sound confusing, but it makes sense when you understand the timing of the release of those hormones. The first hormone the body enacts to fight stress is called CRH (corticotropin releasing hormone). It is the bodies’ primary driver of your sympathetic nervous system (“fight or flight” mode). CRH prepares your body to combat stress by increasing your anxiety, briefly enhancing your cognitive abilities, and suppressing your appetite. This explains why you initially do not feel any hunger in the middle of a stressful situation. CRH is the bodies’ natural prioritization of energy to fight a demanding or anxious situation rather than expending useless energy worrying about what you are going to eat for lunch.
Stress fighting hormones do not begin and end with CRH. In order to continue combatting stress, your adrenal gland triggers the release of other hormones called glucocorticoids, which are the bodies’ main mechanism to mobilize and restore energy during and after stress. The production of glucocorticoids is significantly longer than CHR. They take anywhere between minutes and hours to produce and they take even longer to eventually leave your bloodstream. On the other hand, CRH production and elimination occurs in a matter of seconds.Ironically, glucocorticoids also have the opposite effect of CRH in terms of appetite. They increase appetite, particularly for starchy or sugary foods.
To make things a little more clear, let’s look at real life example of how our bodies respond to stress. The other day I becameoverwhelmed with the amount of lesson planning I needed to do at school, program design for my fitness clients, and unfinished chores around the house. I had a few minutes of a stressful “melt down”, which unfortunately, usually manifests itself in anger for me. During this time, my body immediately begin releasing CRH and I remember losing my appetite for breakfast, which is usually my favorite meal of the day. All I wanted to do was get to work. However, after a couple hours had gone by, I remember having a sudden craving for a salty, starch filled lunch. By that time, the appetite suppressing CHR had already left my system, whereas the appetite stimulating glucocorticoids were still hanging out in my blood stream.
Dangers of chronic stress
Our body is intelligent. It decreases appetite to focus on combatting stress and then increases it to restore lost energy after the stressful situation is over. The problem is when stress becomes chronic, like it usually is for most Americans. Rarely do we have a day where we have one stressful situation that goes away after a few minutes. In fact, according to a recent Gallup poll, 80% of Americans reported feeling stressed frequently throughout their day.
Think about what impact this has on appetite control from the regulation of stress hormones. I wake up late for work and rush in the car to get to school. My second period class is not understanding what I am teaching them, my lesson becomes pointless, and the kids begin to act out. I leave work late trying to fix my lesson for the next day and become late for my personal training appointment. I get home and our dog has thrown up all over the carpet because he ate important paperwork on the table. All this just happened to me last week. How did my body respond to it? With continual bursts of CHR, followed by increased glucocorticoid levels, which result in myevening cravings of starchy, sugary junk food.
Decrease chronic stress, decrease cravings
I hope that you have a better idea why a new exercise routine or diet is not going to help alleviate your nighttime junk food cravings. The only, yet most challenging, solution is to find ways to reduce daily stress. Although an entirely different post would be needed to dive deeper in how to manage stress, the following are a few practical steps that you can start implementing right away:
• Reduce training stress. Instead of beating up your body five to six days a week with high intensity workouts on top of high levels of daily stress, try replacing a couple of those workouts with something easier like a bike ride or walk.
• Spend a few minutes each day practicing diaphragmatic breathing. This will help turn on your parasympathetic nervous system and get you out of the sympathetic, or fight or flight mode.
• Sleep more. Getting more than seven hours of sleep each night helps your body appropriately regulate stress-fighting hormones and leaves you better equipped to manage stressful situations.
• Find a coach or community to hold you accountable. Trust me; I have tried to fight stress with “individual willpower”. It does not work. The best thing I ever did for my health was seek out a coach who knew when to push me, when to hold me back, and when to remind me to relax.