Autism spectrum disorder, or ASD, is a neurodevelopment disorder characterized by impaired social interaction and communication, as well as restrictive, repetitive patterns of behavior. ASD affects roughly one in 68 people and is more common among males than females. A 2014 study showed that sulforaphane reduces communication impairments and behavioral symptoms in young men with autism.

Sulforaphane demonstrates low toxicity. It has been shown to reverse physiological anomalies commonly associated with ASD, including increased oxidative stress, mitochondrial dysfunction, and neuroinflammation.

The placebo-controlled, double-blind, randomized trial involved 44 young men between the ages of 13 and 27 years who had been diagnosed with moderate to severe ASD. The authors of the study gave 29 of the participants sulforaphane derived from broccoli sprout extracts and gave the remaining 15 participants a placebo. They received their respective treatments for 18 weeks, followed by four weeks without treatment. Sulforaphane doses ranged between 50 and 150 micromoles (~9 milligrams and 26 milligrams, respectively). The participants' parents, caregivers, and physicians provided assessments of the young men’s behavior using the Aberrant Behavior Checklist, Social Responsiveness Scale, and Clinical Global Impression Improvement Scale (CGI-I).

After 18 weeks on the treatment, the participants who took the placebo experienced little change, but those who took the sulforaphane showed marked improvements in their behaviors. In particular, the CGI-I scores reflected improvements in social interaction, behavior, and verbal communication. After the sulforaphane treatment ended, the participants' scores rose toward pretreatment levels on all assessments.

These findings suggest that sulforaphane ameliorates many of the behavioral symptoms associated with ASD. A follow-up study reflected similar effects.

• Link to full study.