Exploring the Concept of 'Fried Rice Syndrome' and Evaluating the Fear of Consuming Leftovers
Hidden within your recently heated-up fried rice, there's a potential deadly bacterial threat—at least, that's what you might believe after watching one of the latest viral videos circulating on TikTok and other social media platforms. There is a grain of truth to this claim, and it's important to proper store your leftovers, but the risks of so-called fried rice syndrome shouldn't be overstated.
The thriller of fried rice syndrome has resurfaced online every now and then, most recently in a TikTok video from cooking and home goods company Food52, posted last week. In the video, food editor Emily Ziemski discusses the small villain behind the syndrome, Bacillus cereus. And to Ziemski's credit, the central idea of the video is factual.
The Invincible Germ
B. cereus, a close relative of the bacteria responsible for anthrax, is a well-known perpetrator of food poisoning. Disease-causing strains of B. cereus produce a variety of toxins when actively growing, and it’s these toxins that make people sick. B. cereus bacteria are abundant in the environment, particularly in soil, so they can easily find their way into our food supply. Though they can be contracted from various foods like dairy, beef, and vegetables, the illness they cause is frequently associated with reheated fried rice and other leftovers.
B. cereus bacteria can transform into a spore-like form to survive unfavorable environments, such as very cold and hot temperatures. Once the conditions are favorable again, they begin to grow and produce toxins at an alarming rate. This is why cases of illness are often linked to improperly stored foods.
A typical scenario plays out like this: You leave an untouched bowl of rice that was initially contaminated with B. cereus spores out on the kitchen counter for several hours. During that time, the bacteria multiply uncontrollably. If the person eats the food at that moment, they can become infected and soon enough become sickened by the bacteria's toxins. Even if they reheat the rice to kill all the active bacteria, there is one specific heat-resistant B. cereus toxin that can remain in the food and make us ill.
According to professional guidelines on B. cereus prevention, foods are at risk of contamination when they're left alone for an extended period at temperatures ranging from 41 to 135 degrees Fahrenheit. Therefore, hot foods intended to be held for an extended time should be kept at temperatures above this range, and in general, cooked foods meant to be leftovers (especially meat) should not be left out at room temperature for longer than two hours.
However, the TikTok video may give you the impression that leftover rice will inevitably make you seriously ill if it's kept out even a tiny bit too long, and that's not entirely true.
A Real but Modest Troublemaker
For instance, while the typical symptoms of B. cereus illness are uncomfortable (either nausea, vomiting, and cramps or diarrhea, depending on the type you contract), they are relatively mild, with most cases recovering within a day. B. cereus can cause severe, even fatal illness, but only infrequently and usually under specific circumstances, such as someone having a compromised immune system. The severity of the illness can also depend on the amount of bacteria or toxin that a person ingests. In an infamous case that received renewed attention last fall, for instance, a 20-year-old man is believed to have died from eating B. cereus-contaminated pasta that was left at room temperature for an astonishing five days before he reheated it.
Furthermore, B. cereus illness is not particularly common in the U.S. According to a 2011 study from the Centers for Disease Control and Prevention, approximately 63,000 cases of foodborne B. cereus are estimated to occur annually in the U.S., along with 20 hospitalizations (the study also estimates zero yearly fatalities on average, but these still may happen from time to time). For comparison, the most prevalent foodborne infection—norovirus—is thought to cause around 5.5 million cases of food poisoning every year.
All said, B. cereus illness can and does occur frequently enough to be a genuine public health concern. And despite the speculation of many commentators on Food52's TikTok and other social media posts, people in rice-loving regions of the world, such as Asia, are not immune to it.
According to a 2020 study from China's CDC, for instance, B. cereus was the fourth most common bacterial cause of foodborne outbreaks with a known culprit in the country between 2003 and 2017. Another paper published last year found that there were over 400 reported outbreaks of B. cereus within China from 2010 to 2020, which led to at least 7,892 cases, 2,786 hospital admissions, and five deaths (as is often true with foodborne illness, the actual number of cases is likely higher).
Absolutely, you ought to be cautious when handling and re-heating your food, particularly if you're susceptible to foodborne infections due to medical conditions. This extra caution is crucial. Moreover, it's wise to discard that five-day-old takeout container sitting on the kitchen counter. However, aside from unusual situations, there are significantly more perilous elements in the world than a routine bowl of re-heated rice.
The study from China's CDC in 2020 revealed that B. cereus was the fourth most common bacteria responsible for foodborne outbreaks with known causes in China between 2003 and 2017. Although B. cereus can cause severe illness under specific circumstances, such as in individuals with compromised immune systems, a 2011 study from the Centers for Disease Control and Prevention in the U.S. estimated that only 63,000 cases of foodborne B. cereus occur annually, along with 20 hospitalizations.
As technology advances in the field of food science, new methods for detecting and preventing foodborne pathogens like B. cereus are being developed. For instance, researchers are exploring the use of machine learning algorithms to predict food spoilage and identify potentially dangerous bacteria. With the help of such advancements, the future of food safety looks promising, ensuring that we can enjoy our favorite dishes, such as fried rice, without the fear of foodborne illness.
