While a lot of health factors feel uncontrollable, diet is completely in our hands and plays a crucial role in longevity. Even small tweaks to how we eat can impact our lifespan.

Dan Buettner, a National Geographic fellow, founder of Blue Zones LLC, and author of The Blue Zones American Kitchen: 100 Recipes to Live to 100, has studied the daily habits of those who live in blue zones where people live about a decade longer than the average (think, Sardinia, Italy; Okinawa, Japan; and Ikaria, Greece).

After collecting his research and distilling some of the lessons of the blue zones to his book, Buettner says the advice can be applied to your weekly grocery run—and it’s easier than you may think.

Bottom line: “put your whole-food plant based glasses on and walk through your grocery store,” Buettner tells Fortune.

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With this basic principle in mind, focus on ingredients you find tasty.

“Find the ingredients you love, and if you can learn how to combine them to make something delicious, you’re on your way to eating to 100,” he says.

Read more: Fortune