How Long Can Pizza Sit Out And Why?

logo by Editorial Staff | Updated on August 3rd, 2022

Exact Time: 2 Hours

We’ve all experienced an overabundance of our favorite foods, especially pizza. But how long can a box of pizza remain out, refrigerated or not, and still be edible? In this article, you’re going to discover.

person picking sliced pizza

Is it safe to leave out pizza?

Perishable food, including pizza, is not safe to consume if left out at room temperature overnight, according to the United States Department of Agriculture (USDA).

According to the USDA, this is true even if your pizza does not include any meat ingredients. Keep cheese, a significant component in most pizzas, in the refrigerator to limit the danger of contamination with foodborne pathogens.

How Long Can Pizza Be Left Outside?

It is critical to consume the pizza appropriately after it has been prepared. Pizza that has been prepared and left out in the open might be hazardous to one’s health.

The pizza may be left out for about 2 hours before it harms one’s health. Pizza is often consumed on a hot source, such as an electric oven or a wooden oven with burning wood.

Why is pizza left out for so long?

Pizza is one of the cheapest foods in the world, and it can be found practically anywhere in cafes and restaurants.

Pizza has a high salt, fat, and food energy level. It has around 5,101 mg for every 36cm or 14 inches on the food chain. Eating frozen meals can occasionally have negative consequences. The packaged foods include a high salt content.

People who eat pizza regularly have a higher risk of cardiovascular disease and intestinal cancer than those who sometimes eat it.

Pizza consumption in Italy is increasing, as evidenced by medical studies and benefits. Overconsumption harms one’s health since it includes a lot of fat.

What Pizza Toppings Promote Bacterial Growth the Fastest?

Bacteria prefer sweet foods like sweet pizza sauce and gluten-heavy pizza dough.

As a result, all pizza is an immediate target. Pineapple, tomatoes, and other fruity toppings help. Mold also enjoys cheese.

While you may enjoy additional cheese on your deep dish pizza, so may other living species. Cured meats, such as pepperoni, are the most durable.

Is it safe to eat pizza that has been left out all night?

The quick and simple answer is no, you cannot consume pizza that has been left out overnight. As unfortunate as this may be, it is advisable to follow the official USDA instructions and avoid eating items that have been left out of the refrigerator all night.

Nothing can preserve your pizza if you leave it out overnight. Reheating it or scraping off the top layer will not help since the germs will have already penetrated the deeper sections of the dough.

As a result, if you intend to eat your pizza the next day, remember to store it in the refrigerator. The pizza will be safe to consume for two to three days due to the cool temperature.

What Happens If You Eat bad Pizza?

Pizza is a prominent source of typical food poisoning, with symptoms including nausea, diarrhea, vomiting, and severe illness.

If you consume a pizza left out of the fridge for an extended period, the germs will most certainly produce serious food poisoning symptoms.

The severity of the symptoms will be determined by the pizza’s quality and how your gastrointestinal system manages the germs. Food illness caused by faulty pizza, on the other hand, should not put you in any significant or life-threatening danger.

Is it possible to kill bacteria by reheating pizza?

There’s a rumor that reheating pizza after it’s been out of the fridge for too long might eliminate bacteria. While this is somewhat true, you should use caution while reheating leftovers.

Reheating any meal above 165 degrees F will destroy most of the germs. However, just because you microwaved the meal doesn’t imply eating is completely safe.

Even if the bacterium is destroyed, the poisons it produces stay in the meal. These poisons are exceedingly harmful and can result in various food poisoning symptoms.

As a result, warming pizza will not make it safe to consume. Another thing to remember is that reheating meals more than once will increase the number of toxins and bacteria.

How to Spot Bad Pizza

Although not perfect, your senses are typically the most trustworthy instruments for determining whether or not your meals have gone rotten.

The first indicator of rotten pizza is a hard and dry texture that is still safe but not particularly flavorful.

A ruined pizza may also emit a putrid stench and turn moldy if kept for an extended period.

Bacteria cannot be identified until it has begun to grow on your pizza.

Except for a somewhat dry texture that may be difficult to identify from poor cooking, the pizza will appear the same for a long time after it has been infected.

You may eventually observe mold growth or black marks, but you know the pizza is bad by then.

If you have to question it, it’s best not to risk it unless you don’t mind sleeping next to a toilet.

Food Poisoning Caused by Bacteria

What happens when you eat pizza that has germs growing on it?

You absorb the germs, and if you consume enough of them, you will become unwell.

The specific symptoms and their severity vary depending on the sort of bacteria growing on your pizza and how long you left it out.

Bacillus Cereus

Bacillus cereus produces spores that multiply every 20 minutes.

Those who are infected will develop symptoms such as stomach discomfort, diarrhea, and other digestive disorders in around six hours. The problem normally resolves itself within 24 hours.

Toxins left behind by bacteria will not be destroyed by heat. Bacillus cereus is derived from the pizza’s raw materials, such as wheat or veggies.


Listeria, which was once harmless to food, evolved from feeding on cattle and sheep to eating on human food. Bacteria populations will more than double in 1.5 days.

While slower than some of the other germs on the list, Listeria is incredibly tenacious. It will continue to develop in both hot and cold weather conditions.

When your pizza becomes contaminated, that’s the end of it. Fortunately, the flu-like symptoms are usually minor.


While Salmonella, a bacterium that targets the gastrointestinal tract, does not thrive on uncooked pizza, it contaminates cooked food when infected equipment (such as a pizza cutter or a spatula) comes into touch with the meal.

Salmonella can also be contracted if your pizza is undercooked.

Salmonella may be killed by heat.

Staphylococcus aureus

While most cases are mild to severe, S. aureus can cause fatal blood infections and pneumonia.

Because these germs may be present in our respiratory system, they can be transferred to people’s hands when they cough.

It can then go onto your pizza if not thoroughly sterilized.

When you leave your pizza out, germs develop poisons that are not destroyed by heat.

How to store your leftover Pizza

When keeping pizza in the fridge, use a sealed container or bag. Though there are no health risks to storing your pizza in the box it arrived in; it dries up quickly.

Keeping it in a sealed container will retain the moisture and result in much better-tasting pizza when reheated. Pizza will keep in the refrigerator for three to four days. After that, I’d toss it away.

You may also keep the leftover pizza in the freezer. Use a securely sealed container or bag to prevent it from drying out. Leftover pizza can keep in the freezer for about 2 months.


Pizza is a highly popular meal in today’s fast-food culture. It is quite sweet and attractive, but it may have certain harmful effects if not ingested with correct safeguards. Eating spoiled food is extremely hazardous to one’s health. In rare situations, it can cause serious food poisoning.


Editorial Staff

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