Back in the 1980s, tobacco giants began aggressively expanding into manufactured foods, buying up some of the biggest food firms. For example, Philip Morris used to own Kraft General Foods and RJ Reynolds owned Nabisco. This was the era when ultra-processed food production really ramped up in the U.S., Schmidt says.

She says tobacco firms had spent decades amassing research on how to make cigarettes more pleasurable and addictive with chemical additives. And she says internal company records show they deliberately applied this knowledge to food manufacturing.