Description:Monomethyl fumarate (MMF) and its prodrug dimethyl fumarate (DMF) are currently the most widely used agents for the treatment of multiple sclerosis (MS). However, not all patients benefit from DMF. We hypothesized that the variable response of patients may be due to their diet. In support of this hypothesis, mice subjected to experimental autoimmune encephalomyelitis (EAE), a model of MS, did not benefit from DMF treatment when fed a lauric acid-rich (LA) diet, in contrast to normal chow (NC) or, more so, a high-fiber (HFb) diet. DMF lacked efficacy in the LA diet fed group despite similar resorption and preserved effects on plasma lipids.