Hair Cortisol and Self-Injurious Behavior Among Children With Autism Spectrum Disorder.

The team snipped a small lock of hair from children with autism. They measured cortisol, a stress hormone stored in hair over months.

Parents also filled out forms about their child's self-injury and general problem behavior. The goal was to see if more severe self-injury matched higher chronic stress.

Kids who hurt themselves often and hard had the highest hair cortisol. Everyday problem behaviors, like tantrums, did not raise the stress marker.

The result was mixed: only the most intense self-injury left a clear biological trace.

Bitsika et al. (2017) flipped the lens and found the same link in reverse: severe child self-injury predicted dysregulated cortisol in parents, extending the stress effect to caregivers.

Curin et al. (2003) seems to disagree, reporting lower cortisol in autistic adults. The clash fades when you note they used a single blood draw, not hair, and did not sort by self-injury severity.

Johnson et al. (2009) first showed mixed cortisol patterns in autistic kids, foreshadowing why only the most severe self-injury, not general stress, raised hair cortisol here.

You now have a quick, painless way to check chronic stress in clients who hit or bite themselves hard. A single hair sample can tell you if the behavior is taking a biological toll, guiding you to prioritize intensive intervention and stress-reduction strategies.