Dr. Francis Marion Pottenger, Jr. was a notable physician and researcher who conducted a groundbreaking study known as "Pottenger's Cats." Born in 1901, he was the son of Francis M. Pottenger, Sr., a California physician who co-founded the Pottenger Sanitorium and Clinic for Diseases of the Chest, a tuberculosis health center in Monrovia. He obtained his medical degree from Otterbein University. Dr. Pottenger was driven by a keen interest in the relationship between diet and health. Pottenger's Cats, conducted over a decade from the 1930s to the 1940s, focused on the effects of diet on successive generations of cats. The study divided cats into groups, feeding them different diets such as raw milk and raw meat, or cooked meat and pasteurized milk. Dr. Pottenger’s experiments resulted in strikingly clear outcomes. Cats on a diet of raw milk and raw meat exhibited robust health, with healthy fur, strong bones, and good reproductive health. In contrast, cats on a diet of cooked meat and pasteurized milk suffered from health issues like weak bones and dental problems. The most intriguing findings emerged when Dr. Pottenger observed the effects across generations. Cats that continued on the inferior diet showed a decline in health that worsened with each successive generation. Evidence of skeletal deformities, allergies, and decreased fertility was identified as direct consequences of poor nutrition. Dr. Pottenger's work highlighted a concept that we know today as epigenetics – the idea that environmental factors can impact gene expression and health across generations. His study emphasized the critical role of nutrition not only in individual health but also in the health of future generations. The Price-Pottenger Nutrition Foundation is named for Weston A. Price, DDS and Dr. Francis M. Pottenger, Jr. Combined, their study of Indigenous nutrition practices and diet research continues to influence scientific understanding of nutrition's role in health, including how we view dietary choices and their far-reaching effects on future generations.