Design: The study will employ a cross-over experimental design with subjects acting as their own controls. Independent variables are the plantar stimulation (intervention), and the characteristics of the subjects that include health history, demographic variables, self reported diet, alcohol, and smoking history, as well as urinary cotinine (a quantitative measure of smoking history). The dependent variables are the assay of intraepidermal nerve fibers in small-fiber neuropathy, clinical assessment of peripheral neuropathy, serum levels of Hgb A1C, and quality of life measurement.