The difference between stress and anxiety
Psychology of stress
Ines Gomez
Psychology of stress
6 min

Stress and anxiety, what’s the difference?

6 min

The terms “stress” and “anxiety” are often used interchangeably. This is because they share many symptoms, and can lead to similar serious diseases when they are not treated properly. However, stress and anxiety are different, and it is important to know the differences to find correct treatments.

Stress and anxiety are both normal reactions to life’s challenges

Stress and anxiety are related. To highlight the similarities between stress and anxiety, some scientists and psychologists have referred to anxiety as an “emotional stress response”. Indeed, both stress and anxiety are normal, adaptive reactions to life’s problems and challenges, such as pressure at work, death of a loved one, or marital or financial problems. They also share many symptoms, including constant worrying, loss of sleep, headaches, stomach aches, muscle tension, racing thoughts and so on.

While stress and anxiety are related, they are not the same. There are important differences between the two. Understanding how they differ is the first step towards finding proper treatment and relief.

Characteristics unique to stress

We have already published quite a few articles on stress. For a recap, please check out our article on “The definition of stress”, which explains what stress is precisely. You could also consult a shorter article about stress here.

An important aspect to stress is that it is defined as a response to an external factor. This applies to psychosocial stress, which is the type of stress that is the most common. Examples of these are a tight deadline (an example of acute stress) or persistent financial trouble or repeated harassment at work (chronic stress).

More often than not, the duration of the stress reactions in your body is limited by the duration of the stressor (the thing that causes stress). Thus, once a stressor has been dealt with, the stress reactions stop and your body returns to its natural and calm state. In this case, the stress reactions have been switched on acutely, preparing you for “fight-or-flight” reactions to deal with the stressor. Your sympathetic nervous system and hypothalamus-pituitary-adrenal axis are turning at full speed. Your heart will pound faster, your breathing goes faster, and blood is moving away from your intestines and into your limbs. This delivers more oxygen to the muscles so that you can fight or run away from the stressor.

These reactions have evolved as survival mechanisms. Very useful for our ancestors to escape from dangerous predators on the savannah, but not very useful to deal with a nasty boss loading you up with work. However, these and still other stress responses are extremely beneficial: they give focus, energy and motivation to deal with the stressor. You will stay alert and take the action necessary to solve the problem at hand.

This positive effect of stress has been anchored in the Yerkes-Dodson law in psychology. It proposes that moderate levels of stress bring you in a state of arousal and are optimal for peak performance. This is what is referred to as “being in a flow” or “being in the zone”. Too much stress, however, gives rise to the fight-or-flight reactions that may be too strong or not adequate. On the flip side, too little stress is not good either, because this will lead to underperformance. You will not be able to put enough energy into dealing with the stressor.

When stress doesn’t stop, it becomes chronic. In a condition of chronic stress, it seems that you are under constant threat. Typical chronic stressors are pressure at work or constant financial worries. For many, chronic stress has arisen during the Covid-19 pandemic. Chronic stress may feel intense and heavy, and can lead to various physical and mental health issues. These include high blood pressure, depression, burnout, insomnia and anhedonia. This is why stress management is so important, and why stress management should be particularly targeted towards chronic stress. Interestingly, chronic stress may lead to increased anxiety, again highlighting the fact that they are related.

Characteristics of anxiety

In contrast to stress, anxiety is often triggered internally by excessive thoughts. These could be judgments about the past or worries about the future. Anxiety can also be raised by thinking about problems that are far away from reality, like thinking that the house will catch fire when you leave the cable of the television plugged in in the evening.

Anxiety can appear in response to a stressful situation, both for acute and chronic stress. For example, your boss comes up to you with a last-minute request while you are already working hard to meet a deadline. Some people will be moderately stressed and use positive energy to deal with the request. For some, the request may be extremely stressful and induces immediate worrying (anxiety) about how to get the job done.

As with stress, and as uncomfortable as it may be, anxiety can be a good thing. It has evolved as an emotion to keep us out of trouble. Anxiety signals that something may not be right, or that there is a threat right around the corner. You become alert and assess whether you have to change the way you are doing things to get out of harm’s way. You may start wondering what is going on, and what you can do to reduce your anxiety.

These sort of questions that you may be asking yourself when you are anxious requires cognitive appraisal of the situation at hand. The prefrontal cortex of our brain is responsible for this. It is the interface between emotion and reason. The prefrontal cortex could thus help you to think critically about your anxiety, and plan and organize steps that you could take to deal with it in a useful manner.

However, as with stress, when you are anxious, the prefrontal cortex is inhibited, and your cognitive abilities are reduced. Instead, the amygdala takes over. The amygdala is the brain’s primal center of fear and anxiety, and it controls the hypothalamus where the stress reactions begin. Anxiety will therefore continue to dominate. This phenomenon is known as the “amygdala hijack”.

When stress becomes chronic, the fear center of the brain takes controlThe prefrontal cortex (green) integrates emotion and executive functions such as decision making. Its activation suppresses feelings of anxiety. However, anxiety can reduce the activity of the prefrontal cortex. If this happens, the amygdala (orange) takes over so that fear and anxiety continue to persist. For reference, the hypothalamus (blue) and pituitary gland (red) are indicated. The face would be on the left side of the drawing.

What are anxiety disorders?

Both stress and anxiety can induce rather severe mental health issues. Some of those are grouped together under the term “anxiety disorders”. Anxiety disorders include generalized anxiety disorder (constant worrying without reason), panic disorder, obsessive compulsive disorder and social anxiety disorder. Related to these are posttraumatic stress disorder and phobia, but they have now been classified as separate disorders.

When taken together, anxiety disorders are the most common mental health condition in the United States (together with substance abuse), as they are in the rest of the world. They affect more than 40 million Americans. Globally, one in thirteen people suffers from anxiety disorders.

How to know when stress or anxiety have turned into an anxiety disorder? An important indication is that they have begun to negatively affect important domains of your life. Think of work and family situations, and also whether you have lost pleasure in things that you liked to do. Symptoms like insomnia, concentration problems, irritability or anhedonia are not specific to stress or anxiety. Therefore, they have to occur for a longer period of time consistently to identify an anxiety disorder, and ideally they can be related to a particular event or feeling that may have served as an external (stress) or internal (anxiety) trigger.

These are obviously rather vague criteria, and the ways stress and anxiety manifest themselves vary from person to person. On top of that, some stress and anxiety are even necessary to feel motivated and energized. However, most people can estimate whether stress and anxiety are manageable or not. The reason most people seek professional help is when they realize that “something” is interfering with their lives. This “something” can often more specifically be identified together with a psychologist or psychiatrist.

Identifying what causes stress and anxiety, and understanding the difference between the two, does not make your stress and anxiety go away on the spot.

Rather, understanding stress, anxiety and where they come from is the first and most important step to finding relief.

Our advice is to listen to your feelings of stress and anxiety. Try to figure out where they come from, alone, with loved ones, or with a psychologist or psychiatrist. The information here on the Stressinsight blog and in our course Surmounting Stress may serve to help you with this. Understanding comes first, treatment comes second. This helps to find relief much faster than when trying out different treatments and strategies in the hope of stumbling upon one that works for you.