Melatonin May Lower Risk of Self-Harm in Young People

Researchers from Sweden found that treating sleep problems with melatonin reduced the risk of self-injurious behavior — especially among adolescent girls with anxiety or depression.

Lack of quality sleep or insomnia tends to go hand in hand with many mental health conditions, including depression and anxiety. Poor sleep is also associated with developmental conditions like autism spectrum disorder (ASD).

In addition, research suggests that not getting enough sleep is also linked to an increased risk of self-harm and suicidal behavior, and taking steps to improve sleep quality might reduce that risk.

Because of the association between mental health conditions, poor sleep, and self-harm, scientists from Karolinska Institutet in Sweden wondered whether the popular sleep aid melatonin could help reduce the risk of self-injury among young people.

Melatonin is a hormone naturally produced by the body that regulates the circadian rhythm and helps induce sleep. It’s also available as a dietary supplement. In Sweden, melatonin is commonly used to treat sleep disturbances in children and adolescents.

To conduct the population-based cohort study, published in The Journal of Child Psychology and Psychiatry, researchers identified 25,575 young people who started melatonin treatment between the ages of six and 18. The team found that over 87% had at least one mental health condition — primarily anxiety, depression, ASD, or attention-deficit hyperactivity disorder (ADHD).

Among the participants, self-harm was five times more common in girls than boys.

The scientists compared the participant’s risks of self-harm the month before melatonin treatment and 12 months after treatment began. They also accounted for other factors that may play a role in self-injurious behavior.

After analyzing the data, the team found an increased risk of self-harm during the month before melatonin treatment. However, in the months after treatment began, that risk decreased by about 50% — especially in adolescent girls with anxiety or depression.

What’s more, these results were similar even after the scientists excluded participants taking antidepressants.

In a news release, first author Marica Leone, Ph.D., says, "this suggests that melatonin might be responsible for the reduced self-harm rates, but we cannot rule out that the use of other psychiatric medications or psychotherapy may have influenced the findings."

Still, the study authors say that although more research is needed, treating sleep disturbances may be an important intervention to reduce the risk of self-harm among young females with mental health conditions such as anxiety and depression.