There's a biological reason why we eat more when we're stressed - and it has a lot to do with sleep
- Many of us are familiar with "stress eating."
- Our brains are wired to seek out foods that will indulge our reward systems.
- Unfortunately, this means sugary, fatty foods which are bad for our health in a number of ways.
When the pressure is on, many of us may find our hands reaching for the biscuit tin. Eating is a common reaction to stress, and a lot of people find comfort in junk food in taxing situations.
There is actually a fair bit of biological truth in the term "stress eating." In the short term, stress suppresses our hunger. The hypothalamus - part of the brain that links the nervous system to the hormone system - produces a hormone that stifles appetite.
Our adrenal glands also pump out adrenaline, which triggers the fight-or-flight response, putting us in an agitated state. If you think about it, it's unlikely your brain would be focused on nourishment when you're highly anxious or alert about something.
In the long term, however, the effects are somewhat reversed. If you're stressed for a prolonged period of time, the adrenal glands start releasing cortisol, another hormone which can increase appetite. It can also increase our motivation, including the impulse to eat.
Lack of sleep can also be a factor
If stress is causing a lack of sleep, which it often does, this has been shown to increase appetites too. One study, published in the European Journal of Clinical Nutrition, found that sleep-deprived people on average consume an extra 385 calories per day.
When the stressful period is over - the exam season has finished, or you've completed that big project at work - your cortisol levels should fall, and you should be able to sleep again. But if you can't shake the anxious feeling, your cortisol levels will probably stay high, leading to a cycle of more and more binge eating.
Unfortunately, we rarely crave healthy snacks like carrot sticks. Instead, we want the kind of foods that indulge our brain's reward system. Sugary snacks like cookies, cakes, and chocolate cause a dopamine response - the happy, reward hormone.
Then, next time you're feeling stressed, you'll seek out these foods because you'll remember they made you feel better.
Sugar can also reduce the cortisol response, according to a study in The Journal of Clinical Endocrinology & Metabolism. Over time, your brain might become dependent on these foods to ease your nerves.
It's also bad for our general health. If we consume a lot of sugar, but we don't actually need that energy to run away from any dangers, we need to get rid of it. The pancreas has to pump out insulin to bring down our blood sugar levels, and if this happens too much over our lifetime we can develop type 2 diabetes.
Stress eating can also make us put on weight. A study published in the journal Biological Psychiatry found that women who reported feeling stressed burned about 100 fewer calories per day, which can add up to 11 pounds of weight in a year.
Channel anxiety into something positive
Instead of turning to food to calm your nerves, there are other ways to channel anxiety into something positive. You could try meditation, exercise to clear your head, or a relaxing hobby like yoga.
At the very least you can increase your chance of getting a good night's sleep by writing down anything that's in your mind before you put your head down, avoiding screens for at least an hour before bed, and making sure you're in a dark room.