Why Does Lettuce Turn Pink When You Cut It (and Is it Safe to Eat)?

If there’s one color we tend to associate with lettuce, it’s definitely not pink. Visualize a head of crisp, green romaine that you’re chopping for a salad. You use half the head and put the rest back in the crisper. A couple days later, when you grab a few leaves to top a sandwich, you notice it’s turned pink around the edges. If you’ve ever prepped lettuce—especially romaine or iceberg—this has happened to you. But why does lettuce turn pink when it’s cut, and is it safe to eat? 

Why Does Lettuce Turn Pink After Being Cut?

It’s a totally natural post-harvest trait, explains Katie Sabatini, RD, LDN, Food Safety & Quality Assurance Manager at Little Leaf Farms. Sometimes called “rusting,” this happens when the lettuce oxidizes polyphenols (a category of health-beneficial plant compounds) as a protective measure against spoilage. In other words, the lettuce is protecting itself from rapid deterioration. Sabatini says that rusting can also be caused by excess moisture and exposure to ethylene gas, a naturally-emitted plant hormone found in abundance in refrigerators. 

“Lettuce can turn pink at any point after harvesting,” says Sabatini, but notes that it’s more likely to occur in a bag or container that’s been opened and put back in the refrigerator. Bruised or cut leaves expedite the rusting process, too.

Is It Safe to Eat Lettuce that Has Turned Pink?

Yep! Totally safe. It also shouldn’t taste any different. “If the discoloration bothers you, you can always pick out any pinkish leaves for a more appealing meal,” says Sabatini.

To ensure your lettuce is still good to eat, focus more on the texture: “Check that the rest of the leaves are still crisp, and they appear vibrant and firm. If so, you can still enjoy your greens as you normally would,” Sabatini says, adding that if you notice a significant amount of slimy or soggy greens, discard the rest of the package to be on the safe side.

How Do You Stop Lettuce from Turning Pink?

Because excess moisture is a culprit of rusting, only wash lettuce leaves as needed, instead of batch-washing them and putting soggy or damp leaves back in the fridge. If you really want to prep a bunch in advance, use a salad spinner to get rid of as much water as possible. And keep the lettuce away from other vegetables, in a properly sealed container or in a separate crisper drawer, to avoid exposure to ethylene gas.