A study published in Proceedings of the National Academy of Sciences shows that a chemical derived from broccoli sprouts may ease classic behavioral symptoms in those with autism spectrum disorders (ASDs).
The researchers say that many of those who received a daily dose of the chemical sulforaphane experienced substantial improvements in their social interaction and verbal communication, along with decreases in repetitive, ritualistic behaviors, compared to those who received a placebo.
The study, a joint effort by scientists at MassGeneral Hospital for Children and the Johns Hopkins University School of Medicine, involved 40 teenage boys and young men, ages 13–27, with moderate to severe autism. Before the start of the trial, the patients' caregivers and physicians filled out three standard behavioral assessments: the Aberrant Behavior Checklist (ABC), the Social Responsiveness Scale (SRS), and the Clinical Global Impressions-Improvement scale (CGI-I). The assessments measure sensory sensitivities, ability to relate to others, verbal communication skills, social interactions, and other behaviors related to autism.
Twenty-six of the subjects were randomly selected to receive, based on their weight, 9–27 mg of sulforaphane daily, and 14 received placebos. Behavioral assessments were again completed at four, 10, and 18 weeks while treatment continued. A final assessment was completed for most of the participants four weeks after the treatment had stopped.
The researchers found that most of those who responded to sulforaphane showed significant improvements by the first measurement at four weeks and continued to improve during the rest of the treatment. After 18 weeks of treatment, the average ABC and SRS scores of those who received sulforaphane had decreased 34% and 17%, respectively, with improvements in bouts of irritability, lethargy, repetitive movements, hyperactivity, awareness, communication, motivation, and mannerisms.
After 18 weeks of treatment, according to the CGI-I scale, 46%, 54%, and 42% of sulforaphane recipients experienced noticeable improvements in social interaction, aberrant behaviors, and verbal communication, respectively. The scores of those who took sulforaphane trended back toward their original values after they stopped taking the chemical.
The researchers caution that the levels of sulforaphane precursors present in different varieties of broccoli are highly variable. Furthermore, the capacity of individuals to convert these precursors to active sulforaphane also varies greatly. It would be very difficult to achieve the levels of sulforaphane used in this study by eating large amounts of broccoli or other cruciferous vegetables.