Overthinking: why rumination and worry get stuck, and what research says helps

Saying “I overthink” or “my mind won’t switch off” describes an everyday experience, not a diagnosis. Researchers usually call this repetitive negative thinking. Definitions vary, but they share three features: the thoughts repeat, they are passive or relatively uncontrolled, and they focus on negative content (Ehring & Watkins, 2008; McLaughlin & Nolen-Hoeksema, 2011). The two best-known forms are rumination and worry. Rumination keeps attention fixed on upsetting feelings and on their causes, meanings and consequences, while worry is a future-oriented attempt to solve a problem in the mind, picturing bad outcomes of something uncertain (Stenzel et al., 2025).

Going over things repeatedly is not always harmful. A 2008 review concluded that repetitive thought can lead to depression, anxiety and physical health difficulties, but can also help people recover from upsetting and traumatic events, prepare and plan ahead, recover from depression and take up health-promoting behaviours. As the principles that decide which way it goes, the review named how negative the content is, the context in which the thinking happens, and whether the thinking is abstract or concrete (Watkins, 2008).

The short answer: people who ruminate and worry a lot tend to have more depression and anxiety and poorer sleep, and in follow-up studies rumination predicted later depression. Much of the evidence is correlational, though, so the direction is hard to pin down, and thinking a lot is not an illness in itself. Approaches that have been studied include shifting attention elsewhere rather than forcing thoughts away, setting aside a fixed time for worry, turning solvable problems into plans, and thinking concretely by asking “how” instead of “why”. CBT generally reduced repetitive thinking by a moderate amount, more so when it targeted rumination and worry directly, and mindfulness-based therapy also reduced rumination moderately. Nothing switches thoughts off at once, and most of the evidence for self-help methods comes from small trials.

This guide covers how rumination and worry differ, why they are hard to stop, how they relate to depression, anxiety and sleep, what you can try on your own and the evidence behind it, how well treatments for rumination and worry work, and when to talk to a professional. mind.io has no rumination or worry test, and this guide prints no scale items and no cut-off scores.

In the response styles theory, proposed in 1991, Susan Nolen-Hoeksema, a researcher of rumination, suggested that people who respond to depression by focusing on their symptoms and on the possible causes and consequences of those symptoms stay depressed longer than people who take action to distract themselves. Rumination, the theory holds, prolongs depression because it lets low mood bias thinking negatively and gets in the way of instrumental behaviour and problem-solving (Nolen-Hoeksema, 1991). In this definition, rumination is a way of responding to distress by thinking passively and repeatedly about one’s symptoms and their causes and consequences, without starting the active problem-solving that might change the cause of the distress (McLaughlin & Nolen-Hoeksema, 2011).

The best-known questionnaire for rumination, the Ruminative Responses Scale (RRS), has 22 items (Allard & Yaroslavsky, 2019). A 2003 study removed the items that overlapped with depressive symptoms and split rumination into two parts: brooding, a tendency to dwell passively on negative feelings, and reflection, a purposeful turning inward to understand and solve problems (Kokonyei et al., 2016). In that study, brooding predicted more depression both at the time and a year later, while reflection went with more depression at the time but, once starting levels were taken into account, with less depression a year later (Treynor et al., 2003; Watkins, 2008). In later research brooding has been consistently linked with depression, while findings on reflection are mixed: some studies found no link with depression, some found no difference from brooding, and some found benefits (Allard & Yaroslavsky, 2019).

A Korean study points the same way. In a survey of 316 adults in the greater Daegu area, where South Korea’s first large COVID-19 outbreak occurred, carried out in early August 2020, people who felt more stressed reported both more reflection and more brooding, but only brooding was negatively related to life satisfaction, and reflection itself was positively related to it. The researchers suggested that under stress reflection may easily turn into brooding. The survey was taken at a single point in time, so it cannot show cause and effect (Kim & Kang, 2022).

A 1983 study defined worry as “a chain of thoughts and images, negatively affect-laden and relatively uncontrollable”, an attempt to solve in the mind a problem whose outcome is uncertain but may be negative (Borkovec et al., 1983). Worry typically circles around possible future threats, imagined catastrophes, uncertainties and risks, and is seen as an attempt to avoid bad events, prepare for the worst and solve problems (Watkins, 2008). One questionnaire for the tendency to worry is the 16-item Penn State Worry Questionnaire (PSWQ). It was built to measure worry as a lasting trait, and it told apart groups of university students who met all, some or none of the diagnostic criteria for generalised anxiety disorder (Meyer et al., 1990).

Rumination and worry were long studied and treated separately, but several studies found a common repetitive-negative-thinking factor underlying both, so today they are seen as largely overlapping. Studies also suggest that the repetitive process itself predicts mental health problems better than what the thoughts are about (Stenzel et al., 2025). This guide therefore covers both together and separates them only where they differ.

One reason worry is hard to stop is that it feels useful. In a study that asked university students who worried a lot, and comparison groups, to rate their reasons for worrying, participants rated motivating themselves, preparing for the worst and avoiding or preventing bad outcomes as the most typical reasons. What set apart the group meeting self-reported criteria for generalised anxiety disorder was its high rating of “distraction from more emotional topics” (Borkovec & Roemer, 1995). In the study that developed a questionnaire on beliefs about worry, positive beliefs (“worrying helps”) and negative beliefs that thoughts are uncontrollable and dangerous were among the factors that each predicted the tendency to worry (Cartwright-Hatton & Wells, 1997).

The way of thinking can matter too. The 2008 review mentioned above named the difference between abstract and concrete thinking as one factor that decides whether repetitive thought turns harmful. In one experiment it describes, people wrote about a failure they had been put through earlier in the experiment, either in an abstract, evaluative way (“Why did you feel this way?”) or in a concrete, experiential way (“How did you feel moment by moment?”). Only among those who wrote abstractly did a stronger habit of preoccupation go with worse negative mood 12 hours later; among those who wrote concretely, there was no such link (Watkins, 2008).

Ruminating while low can make thinking darker. In three experiments with people in a low mood and people who were not, those in a low mood who were asked to ruminate on their feelings and personal characteristics read hypothetical situations more negatively, were more pessimistic about good events in their future and came up with less effective solutions to interpersonal problems. Those in a low mood who were asked to distract themselves were as optimistic and as good at solving problems as people who were not low (Lyubomirsky & Nolen-Hoeksema, 1995). Rumination can feel like a way to find an answer, but the way it gets in the way of problem-solving was later summarised as one of the well-supported parts of the theory (Nolen-Hoeksema et al., 2008).

Forcing thoughts away is unlikely to be the answer either. A meta-analysis of controlled experiments in which people tried not to think a particular thought found a small to moderate rebound effect, the thought coming back more often after suppression, whose size depended on the kind of thought and on how it was measured (Abramowitz et al., 2001). Rather than resolving not to think, the methods below rely on placing attention elsewhere or setting aside a time to deal with the thoughts.

The link between rumination and depression has been studied a great deal. Nolen-Hoeksema reported that, beyond earlier studies in which people who ruminated had more depressive symptoms over time even after taking their starting symptoms into account, rumination also predicted depressive disorders, including new onsets of depressive episodes. Whether depression became chronic, however, was no longer predicted once starting symptoms were taken into account (Nolen-Hoeksema, 2000). A 2008 review summarised evidence that rumination worsens depression, enhances negative thinking, impairs problem-solving, interferes with action and erodes social support, and found that rumination predicts the onset of depression more consistently than how long it lasts (Nolen-Hoeksema et al., 2008).

Rumination is not limited to depression. The same review linked it with anxiety, binge eating, binge drinking and self-harm (Nolen-Hoeksema et al., 2008). A meta-analysis of 114 studies (241 effect sizes) on emotion-regulation strategies and mental health problems found the largest link for rumination, a large effect size, among six strategies (Aldao et al., 2010). Two longitudinal studies, of 1,065 adolescents and 1,317 adults, found that rumination helped explain why depression and anxiety occur together. In the adults, depression at the start predicted increases in anxiety and anxiety at the start predicted increases in depression, and rumination fully mediated both links (McLaughlin & Nolen-Hoeksema, 2011). If you have thoughts of hurting yourself, do not carry them alone: call or text 988 in the US and Canada, or call Samaritans on 116 123 in the UK and Ireland, right away.

Sleep is involved too. A meta-analysis of studies in non-clinical populations (k = 55) found small to medium links between more worry and rumination and poorer sleep quality, shorter total sleep time and taking longer to fall asleep. The correlations were 0.28 for sleep quality, 0.15 for total sleep time and 0.16 for the time taken to fall asleep. The link with sleep quality was somewhat stronger for rumination (0.33) than for worry (0.23), and stronger when sleep quality was self-reported rather than measured with activity monitors (Clancy et al., 2020).

Most of these findings are associations, so their direction needs care: thinking a lot may keep you awake, poor sleep may leave you thinking more, or both. The experiments in the next section, though, show one direction: in people whose mood is already low, ruminating makes mood worse. If sleep problems go on, treatments with evidence behind them are covered in insomnia: what helps, and generalised anxiety disorder, in which worry is central, in the anxiety symptoms guide.

1. Shift your attention. In an experiment, people with mild to moderate low mood and people without were randomly assigned to spend 8 minutes focusing on their current feelings and personal characteristics or on descriptions of places and objects. Among those with low mood, the rumination group became more depressed and the distraction group less depressed; neither condition affected the mood of those who were not low (Nolen-Hoeksema & Morrow, 1993). In another experiment, 76 patients with depression, 3.5 years after inpatient treatment, were put in a sad mood and then randomly assigned to rumination, distraction or mindful self-focus; compared with rumination, both distraction and mindful self-focus clearly eased the sad mood (Huffziger & Kuehner, 2009). In correlational studies, though, people who say they turn to pleasant distractions have not consistently had fewer depressive symptoms (Nolen-Hoeksema et al., 2008). Use distraction to break the loop, and deal with problems that need solving separately, as below. Stray thoughts that keep breaking in while you study or work are covered in the concentration guide.

2. Set aside a worry time. If worries take over your day, the NHS suggests setting a “worry time” of, say, 10 or 15 minutes every day or so before bed to write worries down and look for solutions, and, when a worry comes up at other times, setting it aside for that time (NHS, 2026). In an experiment that randomly assigned 53 people with a strong tendency to worry for 2 weeks, those told to worry only during a 30-minute period at a set time and place each day had larger drops in worry, anxiety, negative mood and insomnia than those told only not to avoid worry, though there was no difference in depression or positive mood (McGowan & Behar, 2013). In a study of 171 high school students aged 16 to 17 who kept a worry log for 6 days, half of whom were asked to postpone worrying to a 30-minute worry period each day, those who postponed reported fewer physical complaints afterwards (Brosschot & van der Doef, 2006). Both studies were short and small, so the evidence is preliminary.

3. Separate problems you can solve from worries you cannot. The “worry tree” described by the NHS helps tell apart problems you can solve now and hypothetical worries beyond your control. If there is something you can do, write a specific plan of what, how and when, and carry it out; for worries you cannot do anything about, acknowledge that and move your attention elsewhere (NHS, 2026). It turns going over things into making a plan.

4. Ask “how” rather than “why”. Concreteness training is an exercise in which you recall a recent upsetting difficulty and go through it step by step: the sensory details of the moment and what was specific about it and its context, the sequence in which it unfolded (“How did it happen?”), and the specific steps and actions to take next (Watkins et al., 2012). In an experiment with 60 people in a low mood, this training reduced depressive symptoms more than a waiting list and a bogus training, and reduced rumination more than the waiting list (Watkins et al., 2009). In a trial of 121 people with major depression in primary care, adding the training to usual care reduced depressive symptoms and rumination more than usual care alone, but the drop in symptoms did not differ from adding relaxation training; only rumination and overgeneralisation fell more than with relaxation (Watkins et al., 2012). In a trial that switched seven components of online CBT on and off for 767 adults with depression, six components, concreteness training among them, did not reduce depressive symptoms on their own, and only absorption training, which helps people engage more directly with positive experiences, had a small effect at 6 months (Watkins et al., 2023). Thinking concretely can be a helpful habit, but it is not a powerful fix on its own.

5. Write tomorrow’s to-do list before bed. In a sleep-laboratory study of 57 healthy adults aged 18 to 30 who wrote for 5 minutes before going to bed, those who wrote a list of tasks for the next few days fell asleep faster than those who wrote about tasks they had completed in the past few days, and the more specific the to-do list, the faster they fell asleep (Scullin et al., 2018). There was no no-writing comparison, and it is a single lab study, so it is too early to generalise, but it is worth trying if tomorrow’s tasks keep circling at night.

6. Change what you do, not only what you think. Rumination-focused CBT was developed from behavioural activation principles (Watkins et al., 2011). Ways to become more active when rumination takes up hours, such as restarting a postponed task in a small way, are covered in the depression guide. How to check whether a worry is true is covered in the cognitive distortions guide, and research on mindfulness meditation in meditation and mindfulness.

A 2025 meta-analysis of 55 randomised controlled trials (4,970 participants), across diagnoses, found that CBT reduced repetitive negative thinking at the end of treatment by a moderate amount compared with control conditions (g = 0.67). The effect did not differ by whether rumination, worry or repetitive negative thinking in general was measured, individual or in-person treatment did not make it significantly larger, and effects were smaller against active control conditions (0.46) than against passive ones such as waiting lists (0.81) (Stenzel et al., 2025). In a 2026 correction, after the authors reclassified some treatments, those aimed directly at repetitive thinking had a larger effect (g = 0.87) than less specific ones (g = 0.48); the authors said no conclusions were affected (Stenzel et al., 2026).

A 2018 meta-analysis of 36 trials (3,307 participants) of CBT for current or past depression found that all treatments in these trials taken together had a moderate effect on repetitive negative thinking at the end of treatment compared with control groups (g = 0.48). Rumination-focused CBT (0.76), cognitive control training (0.62), CBT (0.57), concreteness training (0.53) and mindfulness-based cognitive therapy (0.42) reduced repetitive thinking more than other approaches such as antidepressant medication, light therapy, expressive writing and yoga (0.14) (Spinhoven et al., 2018).

Rumination-focused CBT (RFCBT) was developed from behavioural activation principles to target depressive rumination explicitly and exclusively. In the first trial, of 42 people with residual depression that had not responded to medication, adding up to 12 sessions of RFCBT to usual care improved residual symptoms and remission rates, and the effect was mediated by change in rumination; the trial had no attention control group, though, so it could not show whether the specific content caused the effect (Watkins et al., 2011). In a trial of 131 outpatients with major depression comparing 12 sessions of group RFCBT with group CBT, observer-rated depressive symptoms fell more with RFCBT at the end of treatment (d = 0.38), but rumination itself and depressive symptoms at 6 months did not differ, analyses the authors said may have been underpowered (Hvenegaard et al., 2020).

There are prevention trials too. In a trial of 251 adolescents and young adults with high levels of worry and rumination, randomly assigned to a 6-week group training, an internet version or a waiting list, both versions reduced repetitive negative thinking (d = 0.53 to 0.89) and symptoms of anxiety and depression, with effects lasting to 12 months. The 12-month prevalence of depression, as judged by questionnaires, was 15.3% with the group and 14.7% with the internet training, against 32.4% on the waiting list, and that of generalised anxiety disorder 18.0% and 16.0%, against 42.2% (Topper et al., 2017). In a trial of 235 UK university students with high worry and rumination, the risk of a major depressive episode over 15 months was 34% lower with guided online RFCBT than with usual care, but this was not statistically significant (HR 0.66, 95% CI 0.35 to 1.25), so an effect was not shown; in a subgroup analysis of those with higher stress at the start, the difference was significant. Rumination, worry and depressive symptoms improved significantly in the short to medium term (Cook et al., 2019).

Mindfulness also reduced rumination. A meta-analysis that reviewed 11 studies on rumination in depression found that mindfulness-based interventions reduced rumination by a moderate amount compared with usual care (g = 0.59), while three studies comparing them with other active treatments (medication, behavioural activation and CBT, one each) showed no difference (Perestelo-Pérez et al., 2017). A 2025 meta-analysis of 29 randomised controlled trials (2,535 participants) also found that mindfulness-based cognitive therapy reduced rumination (effect size 0.51), with the effect lasting into follow-up (Wei et al., 2025). There is evidence that reductions in rumination and worry mediate the effects of mindfulness programmes, but most of those mediation studies had methodological shortcomings that rule out firm conclusions (Gu et al., 2015).

Metacognitive therapy works on beliefs about worry and rumination. It sees coping strategies such as worry, rumination, threat monitoring, attempts to control thoughts, avoidance and reassurance seeking as what keeps distressing thoughts and feelings going; it challenges beliefs about worry and rumination through dialogue and behavioural experiments, and has people practise postponing worry and rumination. A meta-analysis of 25 studies (15 of them randomised controlled trials) found that metacognitive therapy reduced the main symptoms treated, mostly anxiety and depression, by a large amount compared with waiting lists (g = 2.06, 9 comparisons), with effect sizes of 0.69 at the end of treatment (8 comparisons) and 0.37 at follow-up (7 comparisons) compared with behavioural activation and CBT. These are symptom outcomes, not measures of worry or rumination, and the authors said trials with more participants are needed before firm conclusions can be drawn (Normann & Morina, 2018).

Thinking a lot is not an illness in itself. The NHS points out that worrying is part of life and that we cannot eliminate it completely or control everything (NHS, 2026). It is different when worry affects daily life and is hard to control: the NHS describes that as the main symptom of generalised anxiety disorder, which may be diagnosed if you often worry about a wide range of things, anxiety affects your daily life, you find it hard to control your feelings and you have felt anxious a lot of the time for at least 6 months. The main treatments are talking therapies, usually CBT, and a type of antidepressant called an SSRI, with talking therapy usually tried first (NHS, 2024).

If worry is hard to switch off, the anxiety check-in (GAD-7), and if your mood is low and things have lost their interest, the depression check-in (PHQ-9) can show where you are now. A self-check is not a diagnosis. If you score 10 or more on the PHQ-9 or GAD-7, or if you answer PHQ-9 item 9 (thoughts of death or of hurting yourself) with anything other than “Not at all”, whatever your total, talk to a professional; mind.io suggests doing so in each of these cases. If you have thoughts of hurting yourself, do not carry them alone: call or text 988 in the US and Canada, or call Samaritans on 116 123 in the UK and Ireland, right away.

If thoughts chain on until work, study or relationships suffer, or poor nights keep coming, seek help: in Korea that can be a psychiatric clinic or a local mental health welfare centre; elsewhere, start with a family doctor or a local mental health service. What a first appointment involves is described in seeing a psychiatrist for the first time. If you have thoughts of ending your life, do not carry them alone: call or text 988 in the US and Canada, or call Samaritans on 116 123 in the UK and Ireland, right away. If you are in immediate danger, contact your local emergency services.

Q. Is overthinking a personality trait or an illness? A. “Overthinking” is not a diagnosis. Researchers sometimes measure the tendency to worry as a lasting trait (Meyer et al., 1990), and repetitive thinking can even help with planning ahead or recovering from hard events (Watkins, 2008). When worry that affects daily life and is hard to control goes on for a long time, a problem such as generalised anxiety disorder may be worth considering (NHS, 2024).

Q. Is there a test for rumination or worry? A. Research questionnaires exist, such as the Ruminative Responses Scale (RRS, 22 items, with 5 items each for brooding and reflection) and the Penn State Worry Questionnaire (PSWQ, 16 items) (Allard & Yaroslavsky, 2019; Meyer et al., 1990). mind.io does not offer them. Two of the 7 items of the anxiety check-in (GAD-7) ask whether you cannot stop or control worrying and whether you worry too much about different things, but it does not measure rumination.

Q. Is it true that most worries never happen? A. One study checked this directly. In 29 people with generalised anxiety disorder who recorded their worries for 10 days and tracked how they turned out over 30 days, 91.4% of the predictions in their worries did not come true, and the most common share per person was 100%. The higher the share of worries that did not come true, the lower the symptoms after treatment (LaFreniere & Newman, 2020). It was a small study of people in treatment, so it cannot be applied to every worry, but writing worries down and later checking them against what actually happened, as in that treatment, is worth trying.

Q. My mind won’t quiet down at night, and I can’t sleep. A. More worry and rumination go with poorer sleep quality (Clancy et al., 2020). You can try writing a specific to-do list for 5 minutes before bed (Scullin et al., 2018) or setting aside a worry time (NHS, 2026); in the worry-time experiment, insomnia symptoms fell too (McGowan & Behar, 2013). If sleep problems continue, see insomnia: what helps for approaches such as CBT for insomnia.

Q. How long does it take? A. It varies between studies. The worry-time experiment lasted 2 weeks (McGowan & Behar, 2013), the prevention training 6 weeks (Topper et al., 2017), concreteness training recommended 15 to 30 minutes a day for at least 6 weeks (Watkins et al., 2012), and rumination-focused CBT ran to up to 12 sessions (Watkins et al., 2011). Rather than giving up after a few tries, keep going for a few weeks, and talk to a professional if things do not improve. But if daily life is badly affected or you have thoughts of ending your life, do not wait: call or text 988 in the US and Canada, or call Samaritans on 116 123 in the UK and Ireland, right away.

Q. My thoughts are so overwhelming that I don’t want to be alive. A. Please do not carry this alone. Reach out to a crisis line right away: call or text 988 in the US and Canada, call Samaritans on 116 123 in the UK and Ireland, or find a line at findahelpline.com elsewhere. If you are in immediate danger, contact your local emergency services.

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