In Too Afraid to Ask, we’re answering all the food-related questions you’d rather not have loitering in the search history of your corporate laptop. Today: Can you actually get food poisoning from leftover rice?
People all over TikTok are claiming that eating leftover rice made them sick. In one clip, a woman in a patterned hospital gown is hunched over in bed like an apostrophe. While horizontal in a dark room, another user whispers into the camera, “Rice poisoning is the worst type of food poisoning I have ever gotten in my entire life.” Yet another, who supposedly just ate a bowl of rice that had been out of the fridge all night, writes: “I DONT WANNA GET DIHARREA,” followed by two sobbing emojis.
What’s the deal? According to experts, toxins produced by a microorganism called Bacillus cereus, are the culprit. If grain-based foods like rice—but also pasta, quinoa, and more—are stored incorrectly after cooking, Bacillus cereus can multiply and cause stomach issues such as vomiting and diarrhea. Though rice poisoning is having a moment on social media right now, fervor around this foodborne illness has been waxing and waning well before TikTok, says Donald Schaffner, PhD, a food science professor at Rutgers University.
That’s partially thanks to a small number of severe cases, which continue to circulate online. In 2003, five siblings from Belgium became ill after eating pasta salad that had been made for a picnic and served again for dinner three days later. The youngest, a seven-year-old girl, died in the hospital after her liver failed. Five years later, a 20-year-old student from Belgium also died after eating five-day-old spaghetti, which he’d made and left out in the kitchen at room temperature. In both cases, Bacillus cereus toxins were identified as the cause of death.
This type of foodborne illness is fairly common: In the US, there are an estimated 63,400 instances of Bacillus cereus–caused cases each year. Typically, they’re mild. “Victims experience vomiting or diarrhea and feel generally terrible, but most go on to make a full recovery,” says Schaffner. “In some cases, though, if a large amount of toxin is ingested, it can cause death.” So, what exactly is Bacillus cereus? Why does it form toxins in foods like rice? And how can you avoid that happening? Here’s what to know.
How does rice food poisoning occur?
Bacillus cereus is all around us: It’s in soil, fresh and marine waters, on plants, and even inside the gut of some animals. That means foods like rice, which are grown in environments where the microorganism is abundant, can easily carry it with them.
At low levels, Bacillus cereus likely won’t make you sick. “We all probably eat the spores or cells on a regular basis with no adverse effects,” says Schaffner. But when the bacteria multiplies in food, two kinds of toxins are formed as a by-product. Schaffner explains: “You can think of them as toxic poop excreted by the organism.” At high enough concentrations, these can make people sick, says Rosemary Trout, DHSc, a food science professor at Drexel University. One causes diarrhea and the other vomiting—that latter of which is more commonly associated with cooked rice.
