San Francisco is the kind of heavily democratic city that the Trump administration often targets.

But there's one issue they agree on. They're both taking aim at ultra-processed food.

In the first lawsuit of its kind, San Francisco is suing 11 of the nation's top food companies,

saying they sell ultra-processed food knowing that they are harmful to health.

By some estimates, more than 60% of the food consumed in the United States is saying they sell ultra-processed food knowing that they are harmful to health.

By some estimates, more than 60% of the food consumed in the United States is ultra-processed.

A growing body of scientific research says diets high in ultra-processed food lead to chronic diseases like obesity, type 2 diabetes, heart disease, and depression.

Earlier, John Yang spoke with Ashley Ger Gearhart, a University of Michigan psychology professor

who studies addiction.

Ashley, we just heard the San Francisco City Attorney say that ultra-processed foods are designed

to be addictive.

Do you agree?

Yes, in my lab that we see that these products can really trigger all the core signs of addiction, that loss of control, those intense cravings, that continue to use even though you know it may be killing or harming you.

How do they do that?

What are in the foods that make people addicted to it?

Yeah, there's a certain addiction playbook that's been used

from tobacco to opiates to sports betting. You take something that exists, typically exist in

nature, like a plant or, you know, a fruit, and you alter it. So it gives just this just right

dose of reward. It stimulates you, but doesn't fully satisfy you. So you want to

keep coming back for more. You can titrate the smell, the flavor, the taste, and then you flood the

environment with it. So your consumers, even if they have a slight moment of temptation, the product is right

at arm's reach. and the next thing they know

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