Breath sampling is a technique used to aid in disease diagnosis and monitoring. Specific compounds found in exhaled breath are attributed to abnormal functional pathways due to various diseases. For instance, acetone and isoprene are indicators of poor glucose metabolism in diabetic patients. This application note investigates the use of GERSTEL TD 3.5+ Tenax TA® thermal desorption tubes for the non-invasive collection of volatile organic compounds (VOCs) from breath to determine biomarkers for glucose metabolism. Distinct changes were seen in acetone and isoprene levels corresponding to blood glucose spikes after a participant ate meals throughout the day.