Why Lettuce Always Makes People Sick

Salads are often synonymous with healthy eating. Except, when the US is struggling to grow spread of cyclosporiasis which has sickened more than 7,100 people in Michigan alone, possibly due to iceberg lettuce provided by Taylor Farms.

In fact, green vegetables are often affected by foodborne illness. There were 2022 multistate E. coli an outbreak linked to romaine used in Wendy’s sandwiches and 173 cases of norovirus linked to Illinois eatery DC Cobb’s. In 2021, BrightFarms recalled salad greens that were sold in several states after 31 people received them. Salmonella. And in 2019, 167 people got sick E. Coli after eating romaine harvested in the Salinas Valley region of California. This is not the first cyclospora outbreak linked to lettuce: In 2020, Fresh Express salad dressings were linked to more than 700 cases of infected people.

Centers for Disease Control and Prevention comparison Crops that cause nearly half of the foodborne illnesses found are leafy greens at the top of the list. So what makes lettuce the biggest source of stomach problems in America?

One big reason is that most people eat it. Lettuce is the second most consumed vegetable in the US behind potatoes. (The recent pandemic keeps the potato king of the US diet. Plus, French fries.) Wraps, subs, tacos, you name a fast food sandwich and it’s got lettuce. Salad-chain catcher and demonstrations across the US. Grocery coolers are stocked with salad dressings, topped with undressed heads of iceberg lettuce and containers of spinach.

Ready-to-eat salads and spring mixes are a big hit because they contain a wide variety of greens, which can come from different fields and places. If one type of lettuce in the mix is ​​contaminated, it can contaminate the entire bag. And because the contaminated lettuce is packaged in many salad and baggies, it can spread germs far and wide.

The way lettuce is grown can also introduce various pathogens. A 2025 education and Cornell University researchers who studied it E. Coli The romaine lettuce outbreak found that most of the contamination comes from irrigation with untreated water used through sprinkler irrigation systems. There are ways to reduce that risk, including changing irrigation methods that don’t directly affect the leaves, but which may require ups and downs.

Satisfactory crushing of lettuce is what keeps it healthy. Since they are eaten raw, who would want wilted lettuce? Like other raw fruits and produce, green vegetables do not go through what is called “killing” – heat, pasteurization, or freezing – which is designed to eliminate pathogens during food production.

The structure of lettuce is another factor that causes it to spread disease. “Most types of lettuce have multiple cracks,” said Jeanne Marrazzo, director of the Infectious Diseases Society of America. “It’s easy for those little bugs to get in there.”

Even pre-cleaning methods at the processing plant do not remove pathogens, which can stick to the leaves. In the case of cyclospora, the pathogen has a thick outer wall, which makes it resistant to many food allergens. Experts say vigorous cleaning that includes washing is the best way to get rid of cyclospora.

Amira Roess, an epidemiologist at George Mason University, said: