Food & Diet

7 Foods That Should Never Be Reheated

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The modern human is no stranger to reheating food. Nobody has time to make food from scratch for every meal (unless you’re like Beyonce or something and can hire somebody to do it for you) and it is far cheaper and far healthier than eating fast and processed food. Sometimes we just like eating leftovers because some types of food are better that way – hello, pizza and birthday cake!

But did you know that reheating can be hazardous to your health?

Reheating, especially at high heats, can change the composition of your food and may cause unwanted side effects. Side effects can range from a mildly upset stomach to a full blown episode of food poisoning.

Some types of food are more dangerous to reheat than others and reheating them should be avoided at all cost. Here’s a list of some of the types of food you should NEVER reheat:


Beets are some of the healthiest vegetables out there. Owing to their deep purple color, they are rich in antioxidants. They are also an unexpected rich source of vitamin C and folate. Despite these health benefits, beets once cooked should be eaten immediately. These nutritious bulbous vegetables lose a lot of their nutrients after cooking, as do most vegetables. Reheating them could convert the nitrates in the beets into cancer causing nitrites.


Chicken, especially the lean parts, is one of the most guilt free ways to get your daily protein requirement. Since it’s so easy to cook, prep and store, many families cook chicken at the start of the week and reheat it whenever the need arises. Although you might think you are serving your family a healthy meal at a fraction of the time it takes to prepare dinner from scratch, reheating chicken might not be such a great idea.

Chicken is especially high in protein. It is natural for proteins to be denatured when heated. This is the exact process that allows us to be able to digest cooked meat better than raw meat. However, repeated reheating of protein could further damage it and cause digestive problems.


Like many other types of meat, reheating chicken can also encourage bacterial growth. Bacteria is present in all our food, cooked or uncooked. However, heating it in high temperatures or keeping it at super low temperatures (like in the fridge) can keep these bacteria from multiplying.

However, thawing and reheating several times allows food to reach temperatures that are ideal for bacterial growth. So the more you thaw and reheat meat, the more you are encouraging the growth of bacteria.


Potatoes are a highly nutritious source of carbohydrates. Despite gaining notoriety because of the many junk food forms it takes (i.e. French fries, chips and tater tots), potatoes are a far better source of carbohydrates than simple carbs, like white rice or white bread.

This all takes a turn for the ugly when people start reheating potatoes. When potatoes and other starchy foods are reheated, whether by frying, microwaving or baking, the increased temperatures cause the sugars found in them [potatoes] to combine with an amino acid to form acrylamide.

Acrylamide is a known potent carcinogen. So, the next time you plan to eat leftover potatoes just eat them cold instead or just let it thaw naturally.


Mushrooms, despite being really healthy, can also become quite toxic whenever they are reheated. This goes for mushroom soup and mushroom risotto too, basically any dish with mushrooms in it. Err on the side of caution and eat mushroom leftovers cold.


Just like beets, spinach is high in nitrates. While nitrates can be useful in maintaining cardiovascular health, reheating food rich in nitrates could help convert the compound into nitrites. Nitrites are known carcinogens. Yikes!


Reheating food with eggs, like pastries, is fine. However, scrambling or boiling eggs and then reheating them after could change the nature of the proteins which may lead to digestive problems. Besides, who the heck reheats boiled eggs?!


Not many people know that rice becomes spoiled quite easily. White rice, especially, is so easily broken down into sugars and is an accessible food source for bacteria. Add to that the warm and moist environment that you can find in a pot of rice and rice leftovers essentially become a Petri dish for microorganisms.

Most people leave rice out at room temperature far longer than they should and then refrigerate the leftovers to be reheated the next day not realizing the rice had already gone bad. This could lead to food poisoning.