What are the Dangers of Cooked Meat Left Out Overnight?

You wake up in the morning and realize you forgot to put the leftover meat in the fridge before you went to bed last night. The meat wasn't raw and it looks fine, smells fine and tastes fine, so eating it should be fine, right? Unfortunately, it doesn't quite work that way.

​Read more:​ How to Know If Pork Has Gone Bad

The USDA notes that there are two types of bacteria: pathogenic bacteria and spoilage bacteria. Spoilage bacteria causes the food to start smelling and tasting funny, but consuming it won't harm you. Pathogenic bacteria, on the other hand, is harmful bacteria that doesn't affect the taste or smell of the food in any way but can cause you to fall sick.

Salmonella, Listeria, Campylobacter, Staphylococcus aureus (Staph) and Escherichia coli (E. coli) are some of the types of pathogenic bacteria listed by the Centers for Disease Control and Prevention.

The USDA explains that pathogenic bacteria thrive between 40 and 140 degrees Fahrenheit. Room temperature usually falls in this temperature range, known as the danger zone. In this temperature range, pathogenic bacteria can sometimes double in number within a span of 20 minutes.

If bacteria can double in just 20 minutes, imagine the numbers if the meat has been left out overnight. The USDA states that any food that has been left out at room temperature for over two hours should be discarded. If the temperature is above 90 F, the window is one hour.

Since pathogenic bacteria doesn't affect the taste, smell or sight of food in any way, you have no way of knowing whether it's there. You may feel bad about throwing away meat that looks perfectly fine, but it's better to be safe than sorry.

In order to be considered safe for consumption, meat needs to be cooked to above 145 F. Ground meat needs to cross an internal temperature of 160 F, and poultry needs to cross 165 F. If you're not eating the meat right away, you need to store it in the refrigerator at temperatures below 40 F.

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According to the USDA, consuming pathogenic bacteria causes food poisoning and results in 128,000 hospitalizations and 3,000 deaths every year. Diarrhea, nausea, vomiting, stomach cramps and fever are the most common symptoms of food poisoning. They can appear as early as four hours after eating contaminated food or as late as a week after eating it. They can last from anywhere between a day to a week.

The USDA notes that some groups of people are more likely to fall sick than others; these include pregnant people, children, older adults and people with weakened immunity, like transplant patients and people with diabetes, kidney disease, cancer or HIV/AIDS. For these groups with increased vulnerability, food poisoning can even be fatal.

Apart from food poisoning, consuming pathogenic bacteria could have other consequences as well. A March 2019 study published in the journal ​Diseases​ links Salmonella consumption to cancer as well as inflammatory conditions like bowel disease. Another study, published in the April 2015 issue of the journal ​Pediatrics in Review​, links E. coli to urinary tract infections, septicemia and meningitis in children.

​Read more:​ What Happens if You Cook Meat After It Has Gone Bad?