Malnutrition can affect all areas of the nervous system. Risk factors for malnutrition include alcohol abuse, eating disorders, older age, pregnancy, homelessness, and lower economic status. Any medical condition that affects the GI tract can also impair absorption of essential vitamins. Nutritional deficiencies have been described in patients with inflammatory bowel disease, fat malabsorption, chronic liver disease, pancreatic disease, gastritis, and small bowel resections. Patients receiving total parental nutrition (TPN) are also at risk for vitamin deficiency and TPN formulations should be carefully formulated to include supplemental vitamins and trace minerals. Neurological complications following gastric bypass surgery are increasingly recognized. Nutritional neuropathies manifest either acutely, subacutely, or chronically. They can be either demyelinating or axonal. A unique class of peripheral neuropathy with coexistent myelopathy, also called myeloneuropathy, can also been seen with nutritional neuropathies. Myeloneuropathy has been described with deficiencies of vitamin B12 and copper. Patients with myeloneuropathy will present with both upper motor neuron and lower motor neuron signs. Peripheral neuropathy may mask the symptoms and signs of the myelopathy presenting a diagnostic challenge. Hyper reflexia may be difficult to assess in the presence of severe peripheral neuropathy and ankle jerks may be absent. Muscle weakness may impair the toe extensors, so Babinski sign may not be present. Besides spinal cord/cauda equina arteriovenous malformation, the clinician should suspect myeloneuropathy when the predominant complaint is gait impairment or bowel or bladder dysfunction in the setting of a peripheral neuropathy.