We are presenting six cases of patients with peripheral polyneuropathy due to malnutrition in settings of prior history of gastric bypass surgery, zinc-based dentures usage, or long-standing alcohol abuse. The clinical presentation in all six patients included sensory, motor, or combined peripheral polyneuropathy and gait instability due to imbalance. All patients included in this case series were found to have low copper levels. Electromyography (EMG) with nerve conduction study (NCS) showed predominantly axonal and length dependent sensory or sensory-motor polyneuropathies. Patients were treated with copper supplements with reportable improvement in their presenting symptoms.