The worry epidemic

In a world where productivity, uncertainty and information overload are constantly competing for space in our minds, overthinking has become an almost socially accepted behavior. But there is an important difference between reflecting on a problem and getting stuck in it. When thoughts stop producing answers and simply start repeating themselves, forming a cycle that is hard to break, rumination comes into play. Psychologists, psychiatrists and neuroscientists now point to this process as one of the main factors involved in anxiety, depression, burnout and low self-esteem.

When thinking stops helping

Not all worry is harmful. In fact, it serves an important function for human survival: it is what allows us to anticipate risks, plan solutions and make decisions. The problem arises when the brain loses the ability to bring this process to a close and keeps revisiting the same ideas without reaching any resolution.

Worry is a natural response to the situations we experience, to uncertainty or to some kind of risk. When it is adaptive, it helps us anticipate problems, plan solutions and make decisions. Once we have worked through that thought, it tends to lose intensity. Rumination, on the other hand, is characterized by the persistent repetition of thoughts, usually negative ones, and the person rarely manages to reach a resolution. Instead of supporting planning, it keeps the person stuck on the problem, says psychologist Deise Silveira, a specialist in Cognitive Behavioral Therapy from Instituto Gilberto Kocerginsky.

This pattern has been drawing increasing attention in psychiatry because it is not just a symptom of emotional distress: it can act as a mechanism that perpetuates various mental disorders. Several studies show that rumination prolongs states of anxiety, intensifies depressive symptoms, hinders recovery from occupational burnout and reinforces patterns of self-criticism. Rumination, therefore, is more than a consequence and appears to act as a link between different forms of mental illness.

The brain that can't get out of "thinking" mode

In recent years, neuroscience has begun to identify the biological basis of this phenomenon. Research using functional magnetic resonance imaging shows that people prone to rumination have altered communication between brain regions responsible for self-referential thinking, memory and cognitive control. A review published in 2025 by researchers at the Royal College of Surgeons in Ireland (RCSI) highlights in particular the role of the so-called “Default Mode Network,” a set of brain areas that remains active when the mind is turned inward, reliving past experiences or imagining future scenarios. When this network stays overactivated, the brain tends to remain stuck in repetitive, self-critical thoughts.

In clinical practice, rumination acts as an amplifier of negative emotions. Instead of helping the brain process an experience and move on, it prolongs the state of alert, keeping thoughts of threat, guilt or inadequacy active for longer. "In anxiety, rumination feeds expectations of threat: the person is always thinking that something bad might happen or that they won't be able to cope with a situation. In depression, it reinforces negative interpretations about oneself, the world and the future. In people with low self-esteem, it strengthens self-criticism and the sense of inadequacy. In burnout, it prevents the person from disconnecting from work, compromising their physical and emotional recovery," explains Deise Silveira.

But why is it so hard to switch off?

One of the most intriguing aspects of rumination is that it often disguises itself as a problem-solving strategy. The subjective feeling is that thinking more will eventually lead to the right answer. In practice, however, the brain simply travels the same paths over and over without producing new solutions.

The person has the feeling that if they keep thinking, they will finally find an answer, understand something that is happening or avoid some problem. This perception keeps them engaged in the thought, even when it has already stopped being productive. In Cognitive Behavioral Therapy, we don't try to eliminate these thoughts, but to change the relationship the person has with them. When they learn to recognize that they have entered this process and redirect their attention to more functional thoughts and behaviors, the cycle gradually begins to lose strength, the psychologist says.

The consequences of this pattern go far beyond emotional distress. It is precisely because of it that many people report a curious phenomenon: they manage to get through their tasks during the day, but when they lie down to sleep or sit in silence, they feel their mind start racing. Without external stimuli to occupy the attention systems, Default Mode Network activity takes over, favoring memories, worries and simulations of future situations. In more vulnerable individuals, this mechanism stops being a normal part of brain function and begins to fuel a virtually automatic cycle of emotional distress.

Rumination impairs sleep onset and quality, reduces the ability to concentrate, interferes with working memory, makes decision-making harder and undermines interpersonal relationships. On this point, Deise advises: "When these repetitive thoughts are frequent, hard to control and cause distress, that is a warning sign. Many patients describe the feeling that 'the mind won't switch off' and say they are always tired precisely because of this excess of thoughts. When this compromises personal life, relationships or work, or comes with persistent symptoms of anxiety, depression or burnout, it's time to seek professional help."

Training the mind to break the cycle

The good news is that rumination doesn't have to be a permanent state. Today, the strongest evidence indicates that interventions such as Cognitive Behavioral Therapy (CBT), especially when combined with mindfulness practices, help significantly reduce this thought pattern. A systematic review and meta-analysis published in 2025 in the journal BMC Psychology, pooling data from 29 randomized controlled trials and more than 2,500 participants, concluded that Mindfulness-Based Cognitive Therapy (MBCT) consistently reduces levels of rumination, in addition to decreasing symptoms of anxiety and depression and enhancing skills such as self-compassion and decentering (the ability to observe thoughts without automatically identifying with them).

In the specialist's view, this happens because the treatment teaches an essential skill: recognizing that thoughts are mental events, not absolute truths. "We often tell patients that thoughts are not facts, and that tends to be very liberating. They start questioning their automatic interpretations more and develop greater cognitive flexibility. Mindfulness helps precisely because it fosters a stronger connection with the present moment, reducing the tendency to stay stuck in the past or to anticipate problems that may never happen. Combined with regular physical activity, adequate sleep, sleep hygiene strategies, and time for leisure and social connection, this set of practices strengthens mental health and weakens the grip of dysfunctional thoughts."

Rather than eliminating negative thoughts (something impossible for any healthy brain), the challenge is learning not to be held captive by them. Science has been showing that the difference between reflecting and ruminating lies not in how many thoughts we produce, but in how we relate to them. In an era marked by overstimulation, pressure to perform and constant uncertainty, developing and maintaining the ability to interrupt our inner dialogue when it stops building answers and only feeds distress is essential to preserving mental health.

Scientific studies cited or used for supplementary information:

- “Functional Connectivity in the Default Mode Network During Rumination in Depression: A Systematic Review” - Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC12241886/ 

- “The Effectiveness of Mindfulness-Based Cognitive Therapy on Rumination and Related Psychological Indicators: A Systematic Review and Meta-analysis” - Available at: https://pubmed.ncbi.nlm.nih.gov/40859383/

- “Rumination and the Default Mode Network: Meta-analysis of Brain Imaging Studies and Implications for Depression” - Available at: https://pubmed.ncbi.nlm.nih.gov/31655111/ (PubMed)