[sounds like a crisis!!!]
Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS)
What Are PFAS?
Per- and polyfluoroalkyl substances (PFAS) are a large, complex group of synthetic chemicals that have been used in consumer products around the world since about the 1950s. They are ingredients in various everyday products. For example, PFAS are used to keep food from sticking to packaging or cookware, make clothes and carpets resistant to stains, and create firefighting foam that is more effective.
https://www.niehs.nih.gov/health/topics/agents/pfc/index.cfm
That might explain why there were so few overweight people in the 50’s... or maybe that’s just my personal experience from the time.