Celiac disease, brain atrophy, and dementia. We report 5 patients who developed dementia before age 60 and were subsequently found to have celiac disease (CD). Intellectual deterioration ranged from moderate to severe, and diffuse cerebral or cerebellar atrophy was found on brain CT. Diagnosis of CD was confirmed by findings of subtotal villous atrophy in jejunal biopsy specimens and positive serum reticulin and gliadin antibodies. Conspicuously, gastrointestinal symptoms were mild. The gluten-free diet failed to improve the neurologic disability except in 1 patient. CD is a multisystem disorder and may play a role in some cases of presenile dementia. Although the pathogenetic mechanisms are obscure, immunologic mechanisms are implicated. 