As the holidays approach and cookie-making is in high gear, we are bombarded with reminders to not consume raw cookie dough.

Most of these reminders stem from concerns about consuming raw eggs in cookie dough and thereby increasing the risk of salmonellosis. However, eggs are no longer the only concerning ingredient according to a study published in the New England Journal of Medicine.

According to the study, flour has been linked to a 2016 E. coli outbreak.

“Our data show that although it is a low-moisture food, raw flour can be a vehicle for foodborne pathogens,” the study said.

The outbreak, which affected 63 people across 24 states, included E. coli symptoms such as stomach cramps, fever, diarrhea and vomiting.

“Linking this outbreak to flour was challenging. Consumption of raw or undercooked flour is not included on most routine state and national foodborne disease questionnaires, so epidemiologists were not initially able to assess whether case patients had consumed raw flour,” the report says.

The outbreak prompted the FDA and USDA to investigate and eventually recall 10 million pounds of flour.