The Food Forum of the National Academies of Sciences, Engineering, and Medicine held a public workshop, Challenges and Opportunities for Precision and Personalized Nutrition, on August 10-12, 2021. The workshop explored potential challenges and opportunities in applying precision and personalized nutrition approaches to optimize dietary guidance and improve nutritional status. Presentations discussed ways to define both approaches, described current research designs and methodologies in diverse populations, and examined limitations in design and data. The workshop also reviewed innovative methodologies and technologies at the various scales of precision nutrition (including the genetic, physiologic/microbiome, individual, and social-ecologic scales) and discussed challenges and opportunities for implementing these approaches equitably, from the perspectives of academia, the federal government, and industry. This Proceedings of a Workshop-in Brief highlights the workshop presentations and discussions.