The observation of neurological dysfunctions resembling multiple sclerosis (MS) seen clinically and/or by MRI in patients with celiac disease has focused attention on the possibility that cryptic gluten sensitivity may be involved in the pathogenesis of MS. Here we study the effects of a gluten-free diet on the course of protracted-relapsing EAE in DA rats, serving as a preclinical model of human MS. The data show not only that this nutritional approach failed to ameliorate development of the disease but rather that it exacerbated the course.