Last Updated: 2009-05-14 15:16:01 -0400 (Reuters Health)
NEW YORK (Reuters Health) - The number of people who deliberately harm themselves, most often by "cutting," seems to be growing, but the underlying reasons for the behavior remain unknown, according to a new report.
Studies suggest that 1 percent to 4 percent of adults have deliberately injured themselves without suicidal intent -- most often by cutting their skin with a knife or razor. But up to 23 percent of teen-agers admit to trying such self-harm -- which suggests that the problem is either becoming more common, or adults are not willing to admit to this past or current behavior.
Exactly why non-suicidal people harm themselves, and why the problem seems to be increasing is not clear, according to Dr. Matthew K. Nock of the department of psychology at Harvard University.
But recent studies offer some possible explanations, Nock reports in the journal Current Directions in Psychological Science.
Self-injurers, he writes, often seem to have the goal of regulating their feelings and thoughts -- cutting may distract them from emotional pain, for example. They may also be trying to show family and friends that they are having emotional problems. In these cases, self-injurers may not know how to talk about their issues, or may have tried and failed before.
There are several theories to explain why people choose self-injury, as opposed to alcohol or drugs, for instance, according to Nock.
One is that many self-injurers have a drive to punish themselves, possibly because they have been abused or criticized repeatedly by other people. Supporting that idea, Nock writes, child-abuse victims have been found to be at elevated risk of self-harm.
There is also some evidence that people who cut themselves have a higher-than-average pain tolerance. This might be related to the body's release of painkilling endorphins during repeated self-injury, but more research into that question is needed, Nock points out.
Some self-injurers, especially teen-agers, may choose it because they have heard about it from friends or the media, Nock notes. And that, he adds, may help explain the "apparent increase" in cutting over the past decade.
Cutting is also, in practical terms, fairly simple for teen-agers, who may not have easy access to alcohol or drugs.
Much still remains to be learned about self-injury, Nock writes, not the least of which is how to best prevent and treat it. Right now, there are no evidence-based treatments that specifically address the problem. Using the recent findings from psychological science, he concludes, may offer the most effective way to pursue this.
SOURCE: Current Directions in Psychological Science, April 2009.
Dr. Sears comments:
I would hypothesize that the increase in this behavior is due to the increasing rates of depression that is occurring at younger ages due to an inflammatory diet and a decrease in omega-3 fatty acids.