We’re spending more and more time working these days. And with more work, more stress often follows. While this can be debated, a lot of people turn to food for comfort. Let’s see how the two of these are connected.
The link between doing work in shifts, doing long working hours, and being in ill-health has been shown to exist by different researchers [1, 2]. While the exact nature of this relationship is a mystery so far, we can find increased amounts of stress in all of them.
Stress is a physiological and psychological response to the demands made by your internal or external environment. This involves external stress from your environment such as your boss being angry with you, but it also involves emotional stress from your internal environment such as feeling overwhelmingly challenged by your workload.
Stress can be short-term (acute) and long-term (chronic), and it can affect you physically and mentally. Work-related perceived stress can be either of those as well. An acute stress response is a response to a one-time event or an event of shorter duration; imagine you are about to give a presentation at a meeting filled with potential buyers. A chronic stress response, however, is a response to something that is being continuously thrown at you. Imagine you’re working on a 6-month project with really annoying co-workers and a boss whose bare presence makes you want to vomit.
The acute response elicits a wide set of physiological changes which I don’t really intend on delving into too deep because I will be doing a full article about the implications of stress soon. They are also not as important now. The chronic response, however, affects you through lifestyle choices and physiological pathways that are being activated because you’re constantly being exposed to stress. It alters certain lifestyle choices we make simply because we have been exposed to chronic stress long enough. Moreover, one major implication of chronic stress is inflammation.
How does stress affect your eating-related hormones?
On a physiological level, short-term stress will stimulate the HPA (hypothalamic pituitary axis) system to secrete cortisol. This hormone uses the help of insulin and ramps up your body for the flight or fight response. To top that off, a part of your brain called the paraventricular nucleus affects the release of corticotropin, another hormone, and your control of your food intake.
The fight-or-flight response is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival.
Chronic stress, however, is accompanied by increased corticosteroid secretion. This seems to disrupt your internal balance which affects your eating. Chronic stress increases your insulin and leptin resistance, the same thing which happens in obese people [3, 4 ]. And this is bad because your brain doesn’t receive and properly understand the signals from your body when you should stop eating.
Moreover, these seems to be a circular relationship between inflammation, stress, and eating. When you’re exposed to chronic stress your body changes the way it metabolizes fat and muscle tissue, and at the same time you become more susceptible to unhealthy food (I’ll explain this shortly). This means that you’re putting unhealthy food in your body, which isn’t functioning properly in the first place, and are making the situation worse by exposing yourself to continuous chronic stress and inflammation through it . This is also supported by the fact that people with high levels of chronic stress have higher results on different oxidative stress markers, a trait of of people with chronic inflammation.
And on that note, recent evidence shows that fatty food stimulates the release of cortisol, a hormone that gets secreted during our stress response [6, 7]. However, not everyone found this fatty food-cortisol connection to occur. 
Another interesting hot topic of investigation is how stress alters our preference for food. Pleasantly looking foods (particularly fatty and sugary food) seem to cut the mentioned HPA axis response, thereby reducing our perceived stress . But not every researcher has found this connection to be true.
So if we summarize a little and put things into perspective: You’re at a new job and you’ve started working on a long and overwhelming project, you will probably start experiencing chronic stress and become more susceptible to unhealthy food. Both of these, chronic stress and unhealthy food, induce chronic inflammation which puts your body under continuous low level stress which you don’t notice but is still damaging to you.
And how does stress affect your food choices?
There seems to be an interesting difference between men and women when it comes to eating during stress. Men seem to not eat during perceived acute stress, while the opposite is true for women [10, 11, 12]. Some even note that we eat more food when we’re under stress even if we’re not feeling hungry. [13, 14]
Emotional eaters seem to be a group of people who especially enjoy eating fatty and sweet food when under stress . This is logical given that they use food as a way to give comfort for themselves, and fatty and sugary food are two main food groups which raise dopamine and serotonin levels, hormones/neurotransmitters that make us feel good.
This tendency of emotional eaters to eat fatty and sugary foods as a response to acute stress seems to translate to all of us when experiencing chronic stress – we’re more likely to eat food that is high in fat and sugar when we have been under stress for a long time. Moreover, we tend to increasingly snack unhealthy foods, as well as eat more food than we need in reality. [16, 17]
In summary: We tend to eat more food when under long-term stress, especially fatty and sugary food. Women seem to be more susceptible to eating food when they’re experiencing short-term stress as well, while men apparently do not eat under perceived short-term stress.