Taylor Farms, one of the nation’s largest producers of leafy greens and fresh vegetables, said on Friday that it would remove its products at the center of a cyclosporiasis outbreak that has sickened more than 1,600 people.

Based in California, the family-owned company is in the spotlight after the Centers for Disease Control and Prevention linked an outbreak of cyclosporiasis to iceberg lettuce that Taylor Farms supplied to certain Taco Bell restaurants, according to two federal officials who declined to be named Thursday night.

The company said in an email Friday that it had “promptly initiated a voluntary removal of product” based on information provided by the Food and Drug Administration this week. “We are committed to taking proactive actions,” the company said.

Taylor Farms was founded in 1995 by Bruce Taylor, the third generation of an agricultural family in California’s Salinas Valley, the so-called salad bowl of the world.

Today, Taylor Farms is a vegetable behemoth, selling more than $7 billion worth of produce each year to grocery stores and restaurant chains. It grows food in more than a dozen states, as well as in Mexico and Canada, and has 30 processing facilities and 25,000 employees. Last year it said it made more than 40 percent of all salad kits sold in American groceries and provided 265 million servings of fresh vegetables each week.

But much of its sales to grocery retailers and restaurants are a mystery. The company — like other food producers — does not disclose which grocery stores or restaurants use its leafy greens or other vegetables.

Adding to the confusion, Taylor Farms sells most of its products to food distributors, who, in turn, sell them to restaurants and grocery stores.

For consumers, that uncertainty made them look at their lunchtime meals a bit differently this week. Was it safe to eat an arugula salad at lunch? Could shredded lettuce be added to a burrito?

“I’m not taking chances. It’s not worth it,” said Caren Bordowitz, who works in marketing at Western Illinois University in Macomb, Ill., as she passed on her usual purchase of a bag of lettuce from her local supermarket.

“Consumers rarely know where their fresh produce comes from, and cannot discern between romaine grown here or grown there,” said Joelle Mosso, the associate vice president of science programs at the Western Growers Association, an industry group.

The C.D.C. is advising consumers to not eat the lettuce served at Taco Bell restaurants in Indiana, Kentucky, Michigan, Ohio and West Virginia. The agency has stated that iceberg lettuce at grocery stores or served in other restaurants is not impacted.

However Sysco, the nation’s largest food distributor, said in an emailed statement Friday evening that it was withdrawing all iceberg lettuce products from Mexico in its supply chain at the request of Taylor Farms.

“We will continue to actively monitor the situation and work with regulators as needed,” the company said, adding that it stopped selling and distributing those Taylor Farms products on Thursday.

On Thursday night Taco Bell said it was removing “potentially impacted lettuce from a supplier in select states.” It did not name the supplier or the states. By Friday evening, the fast-food chain said it had removed the affected Taylor Farms lettuce from its restaurants and supply chain nationwide, based on “conversations with public health officials and out of an abundance of caution.”

Shares of Yum Brands, which owns the restaurant chain, slid nearly 9 percent this week.

Illness from cyclosporiasis is seasonal and tends to peak during the summer months. However, the United States is on track to have more cyclosporiasis cases in 2026 than in any previous year.

And while much of the current investigation is focusing on the outbreak involving iceberg lettuce sold to some Taco Bell locations, health officials are also investigating illnesses and outbreaks in other states that are unrelated, the C.D.C. said in its notice posted Thursday night.

For years, Taylor Foods has emphasized the importance of safety in the lettuce and the other produce it grows, knowing one incident can quickly wipe out consumer trust.

“Our whole industry relies on consumer confidence in the health and safety of our products,” Mr. Taylor said in an interview published earlier this year in Western Farm Press, a trade publication that focuses on farmers and ranchers. “All we can do is make sure we’re taking the steps that we know to take to ensure we’re producing safe food for our fellow Americans.”

The F.D.A.’s investigation into the outbreak appears to be focused on a farm in Mexico that grew the iceberg lettuce, and a facility nearby that shredded it, according to administration officials.

Taylor Farms has two processing facilities in Mexico, one in Baja California and another in Guanajuato.

Food and safety experts said this cyclosporiasis outbreak demonstrated the difficulty in completely eliminating risk from a food supply chain that often stretches across multiple countries and a number of growers, packagers, distributors and sellers who operate under different laws and with different food safety standards.

Over the years, Taylor Farms has been linked to previous outbreaks of food-borne illnesses. In 2013, following three recalls, the company was investigated by health officials in connection with an outbreak of illness that sickened hundreds of people in 22 states that involved greens used at Olive Garden, Red Lobster and possibly other restaurant chains.

More recently, health officials considered the company a likely source of an E. coli outbreak linked to onions served at McDonald’s in 2024 that resulted in 104 illnesses, 34 hospitalizations and one death. In October of that year, Taylor Farms recalled yellow onions.

Mr. Taylor, the company’s founder, has played a powerful role in the fresh produce industry. When two major produce associations joined forces in 2022 to form the International Fresh Produce Association, he was the inaugural chairman.

He has helped shape rules and regulations for the leafy greens industry. After an E. coli outbreak in 2006 killed three people, Mr. Taylor and other growers helped create the California Leafy Greens Marketing Agreement, a food safety coalition funded by growers but administered by the California Department of Food and Agriculture.

Members of the agreement must adhere to food safety practices that go beyond what is required by the federal Agriculture Department or the F.D.A., including scheduled and unscheduled audits of their fields and processing systems.

The Centers for Disease Control and Prevention has linked an outbreak of cyclosporiasis to iceberg lettuce that Taylor Farms supplied to Taco Bell, according to two federal officials who declined to be named.

The C.D.C. said the shredded lettuce was sent to Taco Bell locations in Indiana, Kentucky, Michigan, Ohio and West Virginia. In a notice posted Thursday night, the agency warned the public not to eat shredded iceberg lettuce served at Taco Bell locations in those states.

It remains unclear if Taylor Farms sent the lettuce to other vendors, said one of the officials, who was not cleared to speak for the administration. The C.D.C. has not publicly named Taylor Farms in its investigation.

A spokeswoman for Taylor Farms did not respond to requests for comment.

More than 1,644 people reported eating at Taco Bell before becoming sick with the parasitic infection, and 94 had been hospitalized, according to the C.D.C.

Food and Drug Administration officials also said the lettuce was grown by a single supplier in Mexico. The agency has stepped up screening at the border for the company’s lettuce, according to an agency update posted Thursday night.

The F.D.A. said that other restaurants and stores might be implicated as health officials continued their investigation. And not all Taco Bell locations in the five states had received the affected lettuce.

In a statement Thursday night, Taco Bell said it was voluntarily removing potentially affected lettuce it had received from a supplier in select states. It did not identify the supplier but said that the lettuce from that supplier would be “indefinitely removed” from its supply chain nationwide and would be replaced quickly.

The United States is on track to have more cyclospora cases in 2026 than in any previous year, with 1,645 confirmed cases and 141 hospitalizations across 34 states as of Monday, according to the C.D.C. The agency is investigating more than 5,100 additional illnesses that may have been caused by the parasite, which is transmitted through food or water contaminated with feces.

Health officials are also investigating other cyclosporiasis illnesses and outbreaks in other states that are unrelated to the one linked to Taco Bell, the C.D.C. said in its notice posted Thursday night.

Dr. Natasha Bagdasarian, the chief medical executive for Michigan, said in an interview on Tuesday that not everyone sickened in the state had reported eating at a single restaurant. A supplier that sells a product to restaurants may also stock grocery stores, she said.

Many people who have gotten sick said they did not eat at Taco Bell.

Other states with higher than usual cyclospora cases this year include North Carolina, Illinois, Maryland and Texas.

With around $7 billion in annual revenue, Taylor Farms, based in Salinas, Calif., is one of the largest producers of fresh lettuce and vegetables in the country. Bags of its chopped salad kits can be found at Walmart, Whole Foods, Target and other grocery stores, and it is a leading supplier of lettuce and other produce to many large restaurant chains.

Taylor Farms has been involved in previous food-borne illness outbreaks, including a cyclosporiasis outbreak linked to salad mix that sickened hundreds in 2013. Health officials considered the supplier the likely source of an E. coli outbreak linked to onions served at McDonald’s in 2024 that resulted in 104 illnesses, 34 hospitalizations and one death.

The Washington Post was first to report the connection between Taylor Farms and the outbreak.

Once they are infected, it can take days to weeks for people to develop symptoms. The main symptom is frequent, watery diarrhea. A loss of appetite, cramping, bloating, gas, nausea, fatigue and weight loss can also occur. Though the illness rarely causes serious complications, its symptoms can sometimes linger for a month or more if untreated. Antibiotics are the main treatment.

Tracing cyclospora cases back to a source is a labor-intensive task. Health officials must interview thousands of people who have been infected about everything they ate and drank over weeks and then research the ingredients in each of their meals and snacks and investigate their suppliers. Because of their biology, parasitic infections tend to be much harder to link together than bacterial infections.

The outbreak comes as state and local health departments — which rely on C.D.C. funding to respond to food-borne illness outbreaks — face budget cuts and staff layoffs.

Julie Creswell and Kevin Draper contributed reporting.