Self-harm takes many forms, and most of them aren’t as obvious as people expect. Cutting is the most widely recognized, but research has documented over 16 distinct self-injurious behaviors, including burning, hitting, excessive scratching, and embedding objects under the skin. About 14% of children and adolescents and 3% of adults engage in self-harm at some point in their lives. Knowing what it actually looks like, both on the body and in someone’s behavior, can help you recognize it early.
Physical Signs on the Body
The most common physical form of self-harm is cutting or scratching the skin with a sharp object. But it also includes burning with cigarettes, lighters, or heated metal; carving words or symbols into the skin; punching or hitting oneself; head banging; biting; and rubbing an area hard enough to create a friction burn. Some people pierce the skin with sharp objects or push small items beneath the surface.
These injuries tend to appear on parts of the body that are easy to reach but also easy to hide. The forearms, wrists, front of the thighs, and abdomen are the most common locations. You might notice scabs or scars grouped in a cluster or arranged in a recognizable pattern. Burns may appear in a repeated size or shape. Scratches or cuts often run parallel to one another, which is unusual for accidental injuries.
Tattoos and body piercings are not considered self-harm unless they’re done specifically with the intention to cause pain or damage rather than for decoration.
How Scars Change Over Time
Fresh self-harm wounds look different from older ones, and understanding the progression helps you recognize both recent and past injuries. New cuts or burns typically appear red or pink on lighter skin. On darker skin, fresh scars often show up as dark spots. Over time, the color fades and the scar becomes slightly lighter or darker than the surrounding skin.
The texture of scars varies. Flat scars start slightly raised, then settle level with the skin over weeks. Hypertrophic scars stay raised and feel bumpy when you run a finger over them, but they don’t extend beyond the original wound. Keloid scars, which are more common in people with darker skin, grow beyond the edges of the injury and can become quite prominent. Burns often produce contracture scars, which pull the skin tight as they heal. Repeated injury to the same area can create a layered appearance with scars in different stages of healing, some fresh, some faded, some raised.
Behavioral and Environmental Clues
Because most people who self-harm feel shame or fear about being discovered, the behavioral signs are often more visible than the injuries themselves. Wearing long sleeves or pants in warm weather is one of the most frequently cited indicators. Constant use of wristbands, bracelets, or other coverings that never come off can serve the same purpose. Someone might avoid activities that require exposed skin, like swimming, changing in a locker room, or wearing shorts.
Finding unexplained paraphernalia is another signal. Razor blades, box cutters, broken glass, lighters, or other sharp objects kept somewhere unusual (a bedside drawer, a pencil case, a hidden spot in a room) can indicate self-harm. Frequent use of bandages or first-aid supplies, especially when there’s no clear explanation for an injury, is worth paying attention to. Bloodstains on clothing, towels, or bedding that the person tries to hide or explain away can also be a sign.
Emotionally, people who self-harm often withdraw from friends and family, become more secretive, or show sudden mood shifts. They may seem fine immediately after an episode because the behavior provides short-term emotional relief, which can make it confusing for people around them.
Online Behavior That May Signal Risk
Social media plays a complicated role. Some platforms host communities where people share images or descriptions of self-harm, and a U.S. Surgeon General’s advisory noted that exposure to this content can normalize the behavior, particularly for young people. If someone you’re concerned about is engaging with accounts that post graphic self-harm content, participating in online communities centered on injury, or saving or sharing images related to self-harm, that’s a meaningful warning sign. In some cases, platforms have featured live depictions of self-harm acts that drew significant viewership among adolescents.
Self-Harm vs. a Suicide Attempt
This distinction matters and is often misunderstood. Most self-harm is not a suicide attempt. The intent behind self-harm is almost always to feel better, to release overwhelming emotions, regain a sense of control, or interrupt numbness. Suicide attempts aim to end feeling altogether.
The methods reflect this difference. Self-harm typically damages only the surface of the body. The injuries are painful but not life-threatening. People who both self-harm and experience suicidal thoughts almost never use the same method for both purposes. After a self-harm episode, the person usually feels temporary relief and improved functioning. After a suicide attempt, the emotional state is the opposite.
That said, self-harm does increase the risk of suicidal behavior over time. The risk is highest among people who use more severe methods like cutting and burning (as opposed to hitting or scratching), who have been injuring themselves for a long time, and who use multiple methods. Chronic self-harm with escalating severity is a serious warning sign that the line between self-injury and suicidal behavior may be narrowing.
When Wounds Show Signs of Infection
Self-inflicted wounds carry the same infection risks as any open injury, sometimes more because they’re hidden and not properly cleaned. Signs that a wound has become infected include redness spreading outward from the wound edges, pus or increased fluid leaking from the site, growing pain or tenderness, warmth or swelling, and an unusual smell. A cut that hasn’t shown any healing within four weeks is also a concern. If three or more of these signs appear together, the wound needs medical attention for treatment, as untreated infections can become serious quickly.
What to Look for at a Glance
- On the body: parallel cuts or scratches on forearms, wrists, thighs, or abdomen; clusters of burns in similar shapes; scars in various stages of healing; unexplained bruises from hitting
- In the wardrobe: long sleeves in summer, constant wristbands, reluctance to change clothes around others, avoidance of activities requiring exposed skin
- In the environment: hidden sharp objects, frequent bandage use, bloodstains on fabric, first-aid supplies that disappear quickly
- In behavior: increased secrecy, social withdrawal, mood that seems to improve suddenly after time alone, difficulty explaining injuries
Self-harm rarely looks the way media depicts it. It’s often subtle, hidden, and varied. Many people who self-harm are functioning well in other parts of their lives, which is part of why it goes unrecognized. Noticing the combination of physical marks, behavioral changes, and environmental clues gives a much clearer picture than looking for any single sign alone.