OCD and Cortisol: 7 Real Facts People Get Wrong
If you have OCD and you wake up most mornings with a tight chest and a head already full of doubts, sooner or later you will find yourself searching for OCD and cortisol. It makes sense. Cortisol is the hormone people call the "stress hormone", and OCD feels like stress that never switches off. So it is natural to wonder whether your body is producing too much of it, whether that is causing your OCD, and whether fixing the hormone would fix the problem. The research gives a more careful answer than most websites do. This guide sets out what the studies found, what they did not find, and what it all means for treatment.
Quick answer: A 2019 review that pooled 18 studies found that, on average, people with OCD had higher cortisol levels than people without it. That does not mean cortisol causes OCD, and the studies have not always agreed with each other. Cortisol levels did not track how severe someone's OCD was in one study, and in another, cortisol stayed flat during exposure therapy even when people felt very anxious. There is no cortisol test for OCD and no hormone fix for it. The recommended treatment is still CBT with exposure and response prevention (ERP).
What cortisol is and why it rises in the morning
Cortisol is a hormone made by your adrenal glands. It is one of the main chemical messengers in the body's stress system, which researchers call the HPA axis (hypothalamus, pituitary gland and adrenal glands). When you face something demanding, that system releases cortisol to help you get ready to deal with it.
Cortisol also follows a daily rhythm. It rises sharply soon after you wake up. Researchers call this the cortisol awakening response, or CAR. One research team describes it as "a physiological process, consisting in the increase of cortisol levels as a response to awakening in the morning" in their 2019 study on the cortisol awakening response and obsessive-compulsive symptoms. Everyone has this rise. It is part of how a healthy body gets going in the morning.
That matters for people with OCD, because the morning is often when the doubts start. We wrote about this in our older post on handling the OCD hangover, and it is a big part of why so many readers search for OCD and cortisol in the first place. The question this post answers is narrower: does OCD come with a cortisol problem, and does that change what you should do?
Fact 1: People with OCD had higher cortisol on average
The best single source on this question is a systematic review and meta-analysis from the University of Minho in Portugal, published in European Neuropsychopharmacology in 2019. A meta-analysis pools the results of many smaller studies to get a clearer overall picture. You can read the abstract of the OCD and cortisol meta-analysis on PubMed.
The authors included 19 studies in the review and 18 in the meta-analysis. Their pooled result was that people with OCD had higher cortisol levels than healthy comparison groups, with an effect size of d = 0.76. Studies that averaged several cortisol measurements showed a bigger difference than studies that took just one reading.
In plain terms, an effect size of 0.76 means the average difference between the two groups was about three quarters of a standard deviation. That is a clear difference between group averages. It is not a gap so wide that the groups stop overlapping. Plenty of people with OCD will have cortisol readings in the same range as people without it.
So the honest headline is this: on average, across studies, cortisol tends to run higher in OCD. That is a finding about groups, not a test you can apply to one person.
Fact 2: The studies have not always agreed
The Minho team were open about why they did the review in the first place. Their abstract says that studies in this area "do not always report consistent results regarding the cortisol profile of OCD patients". The meta-analysis was an attempt to make sense of that mixed picture.
It helps to look at one of the individual studies to see why results can vary. In 2013, a smaller study in Frontiers in Psychiatry compared 18 people with OCD to 18 healthy controls. You can read it in full: perceived stress in OCD and its link to obsessive symptoms. The researchers took one blood sample from each person in the early afternoon. People with OCD had higher average cortisol in that sample.
But the authors listed three limits of their own study. Every person with OCD in it was taking medication, which might have affected the results. The study looked at one moment in time rather than following people over months. And the sample was small.
Cortisol can be measured in blood, saliva or urine, at different times of day, once or many times. People with OCD differ in age, medication, other conditions such as depression, and how long they have been unwell. Put all that together and it is no surprise that small studies sometimes point in different directions.
Fact 3: Cortisol did not track how bad the OCD was
This is the finding that surprises most people. In the 2013 study, cortisol was higher in the OCD group, but it did not correlate with how severe their OCD was. Someone with very severe OCD did not reliably have higher cortisol than someone with milder OCD.
The same study also asked people how stressed they felt, using a standard questionnaire called the Perceived Stress Scale. People with OCD reported much higher stress than the control group. When the researchers split OCD severity into its two parts, they found that perceived stress was linked to the obsessions but not to the compulsions.
That fits what many of our clients describe. The stress comes from the thoughts: the what-ifs, the doubts, the images that will not leave. Compulsions bring a short burst of relief, which is exactly why they are so hard to stop. The relief does not last, and the next doubt arrives.
If cortisol were the engine of OCD, you would expect higher cortisol to mean worse OCD. In this study, it did not. That is one reason to be wary of any claim that lowering cortisol will treat OCD.
Fact 4: The morning cortisol rise is normal, and its link to OCD is not simple
Morning dread is one of the most common things people with OCD tell us about. It is easy to blame the cortisol awakening response and assume yours must be broken. The research does not support that leap.
The 2019 study on the cortisol awakening response looked at 183 healthy adults from the general population, none with a psychiatric diagnosis. It measured their obsessive-compulsive symptoms, which everyone has to some degree, and their morning cortisol. The pattern differed by sex. In women, more obsessive-compulsive symptoms went with a blunted (smaller) morning rise. In men, more symptoms went with a bigger morning rise.
The authors also listed the limits. They measured the morning rise on a single day. They could not confirm that people took their saliva samples at exactly the right times. They looked at one moment rather than following people over time. And because nobody in the study had an OCD diagnosis, the results may not apply directly to people with OCD.
So if you have OCD and mornings are hard, here is what the evidence lets us say. Everyone gets a cortisol rise on waking. How that rise relates to OCD symptoms is not settled, and it may even work differently in men and women. Morning dread is not proof that your hormones are faulty. It is far more likely to be your OCD doing what it does at the first quiet moment of the day: finding a doubt and demanding an answer. Our post on OCD and hangxiety covers a related morning pattern.
Fact 5: Exposure therapy feels stressful, but cortisol stayed flat
Exposure and response prevention asks you to face the things your OCD fears and to stop doing the compulsions. It is uncomfortable, especially at the start. You might assume that kind of stress would send cortisol soaring. A group of researchers in Hamburg tested exactly that.
In a 2020 study in Psychiatry Research, they measured stress hormones in the saliva of 51 people with OCD during their very first ERP session and on the day before. You can read the abstract of the ERP and cortisol study on PubMed. People's ratings of their own distress went up on the ERP day before the session started, and rose further during exposure. Their cortisol, though, was statistically no different from the comparison day.
The same team had found the same pattern in an earlier, smaller study. In a sample of 15 patients, they reported that despite clear psychological stress before and during ERP, cortisol did not rise.
Two points stand out for anyone thinking about treatment:
Feeling very anxious in exposure does not mean your body is flooding with cortisol. Your distress rating and your cortisol level are not the same thing.
In an exploratory analysis of part of the group, hormone levels on either day did not predict how well people responded to treatment a month later.
That second point matters. Your cortisol level did not decide whether ERP worked. Doing the exposures and resisting the compulsions is what treatment is built on, and that is within your control in a way your hormones are not.
Fact 6: Nobody has shown that cortisol causes OCD
The NHS is plain about this. Its overview of OCD says "It's not clear what causes OCD." It lists possible factors including family history, brain chemistry, life events such as bullying, abuse, neglect, childbirth or a bereavement, and personality traits. Cortisol is not on the list.
Most of the cortisol research above is cross-sectional, meaning it measured people at one point in time. That kind of study can show that two things go together. It cannot show which came first. Higher average cortisol in OCD could be a result of living with constant obsessions and stress, rather than a cause of them. It could also be linked to other things that often come with OCD, such as depression or poor sleep. Our posts on OCD and depression and OCD and sleep explore those overlaps.
The Minho authors themselves note that stressful events may come before OCD starts or make symptoms worse. That fits what we see in clinic. Stress is often the match, not the fuel. A house move, a new baby or a bereavement can be the point where OCD flares, but the OCD then keeps itself going through obsessions and compulsions.
Fact 7: The treatment is still ERP, not a hormone fix
Because there is no evidence that lowering cortisol treats OCD, the treatment recommendations have not changed. The NHS page on treatment for OCD recommends CBT with exposure and response prevention. It describes this as encouraging you to face your fears and have obsessive thoughts without neutralising them with compulsive behaviours. It says people with mild OCD usually need about 8 to 20 sessions with a therapist, with exercises at home between sessions, and that more severe OCD may need a longer course.
The NHS also describes medicine called SSRIs, which may take up to 12 weeks to help. It warns not to stop an SSRI without speaking to your doctor first. Any questions about medication belong with your GP or psychiatrist, not a blog.
We are not going to tell you to take a supplement to lower your cortisol. We have not seen good evidence that this treats OCD, and medical questions about hormones belong with a doctor. If you have physical symptoms that worry you, such as unexplained weight changes, ongoing exhaustion or changes in your periods, see your GP. They can decide whether any tests are needed.
If you want to understand how exposure work runs in practice, our guide to ERP therapy in the UK explains what to expect before you start.
When researching cortisol becomes part of the OCD
Here is something we see often. Someone reads that people with OCD have higher cortisol. They start to worry that their cortisol is damaging their body. They search for more studies, check their heart rate, ask their partner if they look stressed, and order home hormone tests. Each search brings a moment of relief, then a fresh doubt.
That is OCD at work. The topic is new, but the pattern is the same as any other obsession: a doubt, a rush of anxiety, a behaviour to make the anxiety go away, and a brief easing before the cycle starts again. Reading about OCD and cortisol over and over can become a checking compulsion in its own right.
A few honest questions can help you tell the difference:
Are you reading to understand, or to get rid of a feeling?
Do you feel calmer for a whole day after reading, or only for a few minutes?
Have you read the same studies more than once, looking for a different answer?
Are you asking other people to reassure you about your health?
If the answers point towards a compulsion, that is useful information, not a reason for shame. India Haylor has written about why reassurance keeps OCD going in Don't reassure me!, and the same idea applies here. In therapy, we would treat this the way we treat any other compulsion. You would practise noticing the urge to check, and letting the doubt stay unanswered.
What to do with morning dread instead
You cannot switch off your cortisol awakening response, and you do not need to. What you can change is how you respond to the doubts that show up with it. Here are some steps that fit with ERP:
Name it. When you wake with a knot of dread, label it: "This is morning anxiety. My OCD is looking for something to latch on to." Naming it is different from arguing with it.
Do not start the day with a compulsion. If your first act is to check your phone for reassurance, review yesterday's conversations or search a symptom, notice it. Delay it by ten minutes, then a bit longer each day.
Get up and get moving. Lying in bed gives the doubts room to grow. Getting up does not get rid of the anxiety, but it stops you from feeding it with rumination.
Expect the feeling to pass on its own. Anxiety rises and falls without you doing anything to it. Each time you let it pass without a compulsion, you teach your brain that the doubt was not an emergency.
Bring the pattern to therapy. If mornings are your worst time, tell your therapist. Morning dread can be built into exposure work like any other trigger.
For more morning-specific ideas, see our newer guide to the OCD hangover and the morning dread.
If your distress ever feels unbearable or you have thoughts of harming yourself, please do not wait for a therapy appointment. In the UK you can call Samaritans free, any time, on 116 123, or call NHS 111.
How OCD Excellence can help
At OCD Excellence we treat OCD and nothing else. Nearly every therapist on our team has their own lived experience of OCD, so we know how convincing a morning doubt can feel. Our treatment is built on ERP, delivered in weekly sessions or as an intensive programme in Central London, online, or wherever you are.
We will not test your hormones or promise a cure. What we will do is help you understand the cycle your OCD runs on, including the mornings and the late-night research spirals, and give you the skills to stop feeding it. You can read more about treatment and support for people with OCD, or book an assessment with one of our specialists.
Frequently asked questions
Does OCD cause high cortisol?
Research suggests that, on average, people with OCD have higher cortisol levels than people without it. A 2019 meta-analysis of 18 studies found this. But the studies cannot show which comes first, and higher cortisol may be a result of living with long-term stress rather than a cause of OCD. Not everyone with OCD will have high cortisol.
Can high cortisol cause OCD?
Nobody has shown that it does. The NHS says it is not clear what causes OCD and lists family history, brain chemistry, life events and personality traits as possible factors. Stressful events may come before OCD starts or make it worse, but that is different from cortisol being the cause.
Is there a cortisol test for OCD?
No. OCD is diagnosed through a clinical assessment of your obsessions and compulsions, not a blood or saliva test. The research on cortisol compares groups of people, and the groups overlap, so a single reading cannot tell you whether you have OCD.
Why is my OCD worse in the morning?
Everyone has a natural rise in cortisol after waking. For many people with OCD, the first quiet minutes of the day are also when doubts arrive with nothing else to distract from them. Research on how the morning cortisol rise relates to obsessive-compulsive symptoms is mixed, so morning dread is not proof of a hormone problem. ERP can help you respond to morning doubts differently.
Will lowering my cortisol treat my OCD?
There is no good evidence that it will. In one study, hormone levels did not predict how well people responded to ERP a month later. The recommended treatment for OCD is CBT with ERP, and sometimes medication prescribed by a doctor. Talk to your GP about any concerns about your hormones or physical health.
Does exposure therapy raise cortisol?
In two studies from the same research group, cortisol did not rise during exposure sessions, even though people felt very anxious. The larger study included 51 people with OCD. Feeling distressed in exposure does not mean your body is flooding with stress hormones.
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