Cryptogenic or idiopathic sensory polyneuropathy (CSPN) is a common type of neuropathy seen in patients aged usually older than 50 years. Symptoms and signs are predominantly sensory while motor manifestations are usually mild or absent. Extensive evaluation usually does not reveal a clear identifiable laboratory testing abnormality or electrophysiology testing abnormality. Skin biopsy may be helpful in some patients. This article reviews the etiologies and varied presentation of nutritional neuropathies. Specific syndromes of both nutritional deficiency and excess are reviewed with attention toward epidemiology, risk factors, prevention, and treatment.