There’s a reason why Whole Foods is often dubbed Whole Paycheck—buying all-organic everything can add up. But given the risks of pesticides from most conventionally-grown produce…what’s a healthy, budget-conscious eater to do?

Registered dietitian and You Versus Food host Tracy Lockwood Beckerman, RD, says the easiest way to prioritize your organic spending is to know which foods most often are contaminated with pesticides. In the latest episode, Beckerman explains that every year, the Environmental Working Group (EWG) releases two lists: the Dirty Dozen and the Clean 15. “[These two lists] identify the produce that are the most and least likely to be contaminated by pesticides,” she says.

She says that out of anything, you should do your best to go organic when buying strawberries and kale. “Strawberries have held their spot at the top of the Dirty Dozen list for four out of the last five years, so if there’s one fruit to buy organic, it’s definitely strawberries,” Beckerman says. As for kale, it’s a newbie to the list. While it used to not be on the Dirty Dozen at all, it’s now one of the most contaminated veggies. Good. To. Know.

Check out the full episode above to see what else tops the Dirty Dozen and Clean 15 lists. “Buy organic when you can, but don’t put too much pressure on buying all organic all the time,” Beckerman says. After all, feeling stressed about your food isn’t good for you either!

If you’re confused about genetically modified food, this guide will give you the intel you need. Plus, grocery shopping mistakes even healthy eaters make.