It has been a turbulent period for dining spots that center their menus around leafy greens.

Lettuce costs climbed sharply in the opening months of 2026 because of intense heat in Arizona, which produces about one third of the nation's supply. Eateries now confront the effects of a cyclospora contamination connected to chopped lettuce that has sickened thousands nationwide.

Taco Bell is expected to feel the strongest sales hit from the contamination that started in late June. Health authorities initially linked the cases to shredded iceberg lettuce at locations in Indiana, Kentucky, Michigan, Ohio and West Virginia. The FDA later noted that customers in Illinois, Kansas, Oklahoma and Pennsylvania were also impacted.

On July 17 Taco Bell announced it had pulled shredded iceberg lettuce from Taylor Farms out of its U.S. outlets. Customer traffic has declined, with visits 21 percent below normal levels across the country as of July 23, according to Placer.ai.

Reported cases keep rising, and it appears Taco Bell was not the only source, noted Craig Hedberg, a food safety expert at the University of Minnesota. As the FDA probe continues, officials will gain clearer insight into connected illnesses and the full scope of the outbreak.

Meanwhile diners are staying away. Foot traffic at Chopt, a salad chain with 105 sites, fell 12 percent as of July 23 per Placer.ai. M Science reported that weekly spending at Sweetgreen dropped 10 percentage points versus the prior year in the first half of July.

Chopt did not reply to an inquiry from The Associated Press. Sweetgreen, operating 285 U.S. locations, did not verify any sales decline and stated its items have not been tied to the current cyclospora issue.

We maintain strict food safety protocols and can track our ingredients from restaurant back to farm, the company said.

The outbreak followed an already tough stretch for lettuce growers and salad lovers. The retail price of a pound of iceberg lettuce rose nearly 20 percent from January through June, per government figures. Shoppers paid 33 percent more last month for all fresh lettuce compared with a year earlier, the USDA reported.

Prices promoted by major grocers last week averaged 1.86 dollars for a head of iceberg, 25 cents above the same week a year ago, according to the USDA. A head of red leaf lettuce cost 52 cents more at 1.66 dollars, while a bunch of romaine was advertised at 2.49 dollars, up 1.55 dollars.

Buyers saw relief on certain salad blends, which stores priced 7 to 24 cents lower than the previous year, the USDA noted.

Elizabeth Canales, an associate professor of agricultural economics at Mississippi State University, explained that unusually hot weather in Arizona early in the year caused crops to mature ahead of schedule. This created large supply shortfalls until California output ramped up in late April.

Fuel expenses, which rose after U.S. and Israeli strikes on Iran and Iran's subsequent block on most oil tankers leaving the Persian Gulf, added pressure, Canales said. Lettuce is highly perishable and needs consistent cooling from harvest through sale.

The cold chain must stay intact. Cooling and transport are critical, Canales added.

Lettuce has been connected to several past foodborne illness events, including two 2018 E. coli outbreaks tied to romaine grown in Arizona and California.

Associated Press Writer Mike Stobbe contributed from New York.