Autism Spectrum Disorder (ASD) comprises a heterogeneous group of neurodevelopmental disorders that begin in early childhood. They are characterized by differences in behavior and delays in communication and affect at least 1% of children. Observational studies have now confirmed that behaviors of a substantial percentage of children with autism tend to improve with the onset of febrile illness, which might be the downstream effects of altered metabolic pathways involving increased expression of heat shock proteins (HSP) and cellular stress responses. Sulforaphane, a phytochemical derived from a number of cruciferous vegetables, most notably broccoli sprouts, has metabolic effects that in some ways resemble that of fever. This review paper discusses this "fever effect" and the intracellular effects of sulforaphane as well as the results of our recent clinical trial of sulforaphane in young adults with autism. The accompanying review by Liu et al. describes the cellular actions of sulforaphane and potential biomarkers in the study of ASD.