In mental health, “SH” stands for self-harm, the intentional act of hurting your own body as a way to cope with emotional pain, overwhelming feelings, or distress. It is not the same as a suicide attempt. Most people who self-harm are not trying to end their lives. They’re trying to manage feelings they don’t have other ways to handle. Roughly 17.7% of adolescents worldwide have engaged in self-harm at some point, making it far more common than most people realize.
What Self-Harm Actually Means
The clinical term you’ll sometimes see is “non-suicidal self-injury,” or NSSI. It refers to deliberately damaging your own body tissue without the intent to die. Common forms include cutting, burning, scratching, and hitting or banging parts of the body. Most people who self-harm use more than one method over time.
The distinction from suicidal behavior matters. Self-harm involves different methods (cutting and burning rather than firearms or overdoses), causes less severe physical damage, and most importantly, occurs without the desire to die. In fact, self-harm most often happens in the absence of suicidal thoughts entirely. The latest edition of the major psychiatric diagnostic manual recognizes self-harm as its own separate condition, distinct from suicidal behavior. That said, a history of self-harm does increase the risk of a future suicide attempt, which is one reason it’s taken seriously.
Why People Self-Harm
Self-harm is, at its core, an attempt to regulate emotions. A systematic review of 42 studies found that the most common reasons young people give for self-harming are managing overwhelming emotions, self-punishment, and escaping a feeling of emotional numbness or disconnection (sometimes called dissociation). When someone feels emotionally flooded or, conversely, completely numb and detached, self-harm can temporarily break through in a way that feels like relief.
This fits what researchers call the experiential avoidance model: people self-harm to escape unwanted emotional experiences. The physical sensation creates a moment of focus that overrides emotional chaos, or it generates feeling in someone who otherwise feels nothing. Some people describe it as the only thing that “works” when distress becomes unbearable. Self-punishment is also extremely common. People who feel intense shame, self-blame, or worthlessness may harm themselves as a way of expressing those feelings outward on their body.
The Biology Behind It
There’s a neurobiological component too. Your body produces its own painkillers, natural opioid chemicals like endorphins, that activate when you’re hurt. Research has found that people who self-harm tend to have lower baseline levels of these natural opioids compared to people who don’t. This means their internal pain-relief and reward system may already be running at a deficit, particularly if they have a history of trauma or chronic stress. Self-injury may temporarily spike those opioid levels, creating a brief sense of calm or even relief. Over time, this can become a cycle: the body’s stress-response system stays depleted, and self-harm becomes the way to temporarily restore balance.
Who Is Most Affected
Self-harm peaks in adolescence and young adulthood. Global data shows the health burden rises sharply in the 15 to 19 age group and is highest among people in their early to mid-twenties, though it occurs across all ages. Among adolescents, a large meta-analysis of over 266,000 participants across 17 countries found an overall prevalence of 17.7%.
Gender patterns vary by region. In North America, female adolescents self-harm at roughly twice the rate of males (20.2% versus 8.9%). A similar gap exists in Europe (19.4% versus 12.6%). In Asia, however, the rates are nearly equal between sexes, with some studies finding slightly higher rates in males. This suggests cultural and social factors play a significant role in who develops self-harm behaviors, not just biology.
Self-harm frequently co-occurs with other mental health conditions. The most commonly associated diagnoses are depression, borderline personality disorder (BPD), and alcohol use disorders. In one study of people with frequent self-harm episodes, 44% had a BPD diagnosis, 37.8% had major depression, and over half had an alcohol use disorder. People with BPD often describe self-harm as an almost uncontrollable urge. Chronic pain is also strikingly common in this group, affecting over 72% in one study, compared to about 35% in the general population.
Signs Someone May Be Self-Harming
Self-harm is typically done in private, and people often go to considerable lengths to hide it. Physical signs include unexplained cuts, scratches, bruises, burn marks, or bite marks, often in patterns or concentrated on one area of the body. Scars in rows or clusters are a particularly telling sign. Wearing long sleeves or pants even in warm weather, keeping sharp objects on hand, and frequently explaining away injuries as accidents are all behavioral indicators.
Emotional and behavioral changes can also signal self-harm. These include rapid mood shifts, impulsive behavior, expressions of hopelessness or worthlessness, withdrawal from relationships, and increasing social isolation. None of these signs alone confirms self-harm, but a cluster of them, especially physical marks combined with emotional withdrawal, is worth paying attention to.
How Self-Harm Is Treated
The most well-studied treatment for self-harm is dialectical behavior therapy (DBT), a type of talk therapy originally developed for people with intense emotional responses. Rather than trying to suppress or push away painful emotions, DBT teaches skills for noticing and accepting distressing thoughts and feelings without acting on them. A meta-analysis of studies involving over 1,600 adolescents found that DBT produced meaningful reductions in self-harm behaviors, with large improvements measured from before to after treatment.
Cognitive behavioral therapy (CBT) and problem-solving therapy are also used, focusing more on changing the thought patterns and behaviors that lead to self-harm. For many people, the key shift is building alternative ways to handle the emotional states that trigger the urge. This might mean learning to tolerate distress without needing to act on it, developing healthier coping strategies, or addressing the underlying conditions like depression or trauma that fuel the cycle.
Staying connected also matters. Low-intensity interventions like regular check-in texts, phone calls, or brief messages from a care provider have shown value in reducing isolation, which is a major driver of self-harm. These approaches help people feel that someone is paying attention and that support is available when distress spikes. Emergency contact plans, where someone has a clear path to reach help during a crisis, can reduce the risk of self-harm by making professional support accessible in the moments it’s needed most.
What Self-Harm Is Not
Self-harm is not attention-seeking. The vast majority of people who self-harm do it privately and feel shame about it. It is not a phase that someone will simply grow out of without support, though some people do stop on their own as they develop other coping skills. It is not limited to cutting, which is the most widely recognized form but only one of many. And it is not a sign that someone is “crazy” or beyond help. It is a signal that someone’s emotional pain has exceeded their current ability to cope, and effective treatments exist.