The National Academies Roundtable on Obesity Solutions hosted a public workshop series in April and June 2023 that explored the current science on measures of body composition and body fat distribution. Discussions focused on the strengths and limitations, and clinical and anthropological perspectives of body mass index (BMI) as a measure of adiposity and health. Presentations also shed light on the connection between misinformation and bias and stigma, as well as challenged current communication strategies to improve messaging about obesity.