This document provides a summary of Dr. Larry Smarr's guest lecture on quantifying and monitoring changes in his own body and microbiome over time using various sensors and tests. Some key points: 1) Dr. Smarr reversed the decline in his health by quantifying his nutrition and exercise habits using sensors and making adjustments based on the data. 2) Tests revealed he had chronic inflammation and an autoimmune disease (Crohn's), which he studied further through genetic tests, imaging, and analysis of his microbiome. 3) Dr. Smarr's research showed the potential of precision medicine through quantifying individual health markers and the microbiome over time.