The 1 filling snack Michael Pollan swears by to curb his insatiable craving for potato chips

• Michael Pollan's new documentary, Food Inc. 2, highlights the health harms of ultra-processed foods.
• But even Pollan has his indulgences. As a writer, he snacks a lot. His favorite is potato chips.

Michael Pollan is famously healthy. For decades, he's investigated the brutality hidden inside our food system, and pulled back the curtain on the industry to help consumers make well-informed choices about the foods they buy and eat.

But in a food system where chips, sugary cereals, and soft drinks are often the most accessible, affordable options, even he admits it can be hard to refuse some tasty, processed treats.

"I have a weakness for potato chips," Pollan told Business Insider, ahead of the release of his latest film. "If they're in the house, they'll get eaten."

In his new documentary, Food Inc. 2, Pollan explores America's addiction to ultra-processed foods. Behemoth food companies like Nestle, Coca-Cola, and Kellogg's make billions of dollars producing cheap, hyper-palatable snacks and drinks.

"I think that the more you know about food, the more it shapes your diet," Pollan said. "Doing the sorts of investigations of the food system that I've done changes the way you eat."

Over the years, he's developed a few straightforward techniques to help him eat less processed food more effortlessly.

What makes ultra-processed snacks so addictive?

It's not a matter of willpower. Ultra-processed snacks, like potato chips, are designed to make you want to scarf down the whole bag.

Potato chips are chock full of refined carbohydrates and fat. Research suggests that this combination has an addictive effect on the brain's reward systems, delivering a dose of the feel-good neurochemical dopamine every time you eat one.

The speed at which ultra-processed foods deliver carbs and fats to the gut also plays a role in the cycle. Ultra-processed foods are designed to be quick and easy to consume, and people eat more calories as a result.

How Pollan curbs his chip cravings

Pollan's secret to eating less potato chips is simple: he doesn't buy them.

"I have a practice of keeping mediocre snack foods around — ones that are far from addictive," he said.

He stocks his cupboards with snacks that aren't as tempting, like walnuts. Then, when he inevitably heads down to the kitchen to reheat his coffee or tea, he only grabs a single handful.

"You can't eat that many walnuts. They're not that good — they're kind of dry," he said.

Tree nuts are loaded with healthy protein and fiber —- there are good reasons they're a staple of long-lived communities around the world. Walnuts, in particular, are a rich source of healthy Omega-3 fatty acids, great for your heart, as well as gut and brain health.

But if you're allergic to or just not a big fan of nuts, there are other options. Try kale chips, seaweed snacks, or roasted chickpeas.

And when perusing packaged snacks at the grocery store, make sure to take a look at the ingredients. If there's a long list you don't recognize or can't pronounce, that snack is probably ultra-processed.

"A very good definition of ultra-processed food is it is made from ingredients that no ordinary person keeps in their pantry," Pollan said. So, if you can't remake it at home, it's best to put it back on the shelf.