Things We Should Never, Ever Put In The Microwave

From leftovers that should be an effort-free dinner encore to DIY cleaning hacks gone wrong, there's a long list of items — both edible and otherwise — that should, under no circumstances, be making their way into your microwave oven. It's time to re-meet the foods you’ve probably been reheating wrong all your life and learn which kitchen items should stay far, far away from the microwave.

1. Hard-boiled eggs

If you’ve ever been tempted to cook an egg in the microwave but didn’t go through with it, count yourself lucky. After all, it’s very likely that it would have exploded. Yep! When you heat up an egg inside its shell, water pockets form. And when those boil, the pressure can cause the egg to explode, launching its scalding yolk all over the place.

To reheat hard-boiled eggs, send 'em back to their maker. No, not the hen... but a pot of boiling water! In just 40 seconds, your cold, peeled eggs will be warm and ready to eat once more.

2. Aluminum foil

Most people know that you should never put metal of any kind in the microwave, but it's easy to forget that aluminum foil comes into that category, too. Large pieces of metal in the microwave, such as a thick pan, will simply stop your food from getting hot. But smaller pieces or shards of metal could catch fire. 

The science behind the potentially flammable material goes a little like this... Microwaves turn the foil into an electrical conductor. And when the current surges through, they heat up and burst into flames. So be sure to remove even the smallest bit of foil if you're re-heating last night's burrito!

3. Omelet

Just because some unhinged individual out there thought up the idea of a microwave omelet maker and actually had it made, that doesn't mean you should be wasting your precious money on one! A delicious silky omelet has no place being within even an inch of a microwave!

And the same goes for omelet leftovers, too. Granted — few have bitten into one without consuming the whole thing, but if you ever have some left over, don't sweat it. Reheat it in a pan and your omelette will be almost as fresh as the moment it was made.

4. Celery, leafy greens, and beets

Unlike other foods on the list that become unpalatable when re-heated in the microwave, leafy greens like spinach and kale, along with celery and beets could actually be causing you harm if heated in this way. All of these veggies contain high levels of nitrates. The chemical compound occurs naturally in some vegetables, but it's when they're heated that things an turn toxic.

After a blast in the microwave, nitrates can turn into nitrites, and then into nitrosamines, some of which have been linked to the ill effects of carcinogens. Keep yourself safe by heating these veggies gently on the hob.

5. Styrofoam

Takeout containers in general are bad news for the microwave, but styrofoam containers are even worse. That’s because adding high heat can cause the styrofoam to melt, bonding its toxic chemicals to the food you're trying to warm up.

Styrene, a toxic chemical, is a potential carcinogen. And that’s not really something you want to be putting in your body. Be warned — even if there's no visible damage to the foam, the chemicals may still have leeched out.

6. Pasta in tomato sauce

Lesson 101 when it comes to pasta and sauce is to make sure you mix through just enough sauce so that each delicious pasta piece is perfectly coated with the good stuff. Easy enough! The problem comes, however, when you scrape leftover pasta from the dinner plate. Chances are, it's covered in that delicious sauce you so lovingly stirred through.

Unfortunately, leftover sauce can give the reheated version a weird taste. If you've not set aside any plain pasta separate from your sauce, have no fear! Just toss it in a pan over medium heat with a splash of water instead.

7. Glow sticks

A glow stick plus a microwave surely equals a recipe for disaster. Yes, that’s one equation we were confident didn’t need testing. Nevertheless, in 2014, one boy tried it anyway, hoping his green stick would glow a little brighter.

And that it did — at least until it exploded over his face and clothes. Though he was in serious trouble with his dad, he later appeared in a skit on Comedy Central, and, thankfully, he seemed to have made a full recovery.

8. Hot peppers

Like most things on this list, hot peppers are prone to turning quite literally fiery when nuked. But that’s not the only reason you should keep them far, far away from your microwave.

As well as taking spicy to a whole new level of pain should you be brave enough to tuck in, the component that makes them burn, capsaicin, is highly likely to spread out into the air — so it won’t just be your mouth burning, but your eyes, too.

9. Fried chicken

Microwaving fried chicken is a surefire way to lose all of the crunch from the skin. Not only that, but heading back for seconds on that takeout chicken might leave you feeling unwell if it's not heated evenly.

Keep your chicken crispy — and your gut biome clear — by covering it in foil (shiny side up) and baking it at 350 degrees Fahrenheit for ten minutes. Then, bake it uncovered for another 10 minutes. Trust us, it's worth the wait!

10. Water

Plenty of the food you heat up in the microwave contains water, and it's okay to zap a mug of H2O for a few minutes to make tea if you don't have a proper kettle. But don't boil water for too long in the microwave, as "superheating" can result in an explosion.

“Superheating” means the water has warmed up before vapor bubbles have had time to form. Without these bubbles, the heat can’t be released, so the water will race past its usual boiling point. And then, KABOOM!

11. Bread

How do you solve a problem like rock-hard stale loaves? Well, nuking leftover bread in the microwave certainly isn't it! Not only is it guaranteed to make Italian nonnas the world over shake their rolling pins at you, but you'll be left with a loaf even harder than when you started.

You can avoid their wrath by spritzing leftover bread with water, wrapping it in foil, and baking it for seven minutes at 400 degrees. Then, unwrap it and cook for another three minutes for that perfect crunchy crust.

12. Rice

Microwaving leftover rice turns it into something that's more like hard kibble than the soft, carb-filled delight you love. Not only that, but rice is renowned for causing particularly nasty bouts of food poisoning. If you're stuck with leftovers, be sure to let them cool completely before adding them to the fridge, but keep the time left sitting at room temperature to a minimum. It's during this time when bad bacteria can multiply.

If you're planning to reheat correctly stored rice, start by placing the leftovers in a covered baking dish with a bit of water and butter. Cover the whole thing with foil and bake it for 15 minutes at 320 degrees. Make sure the rice is piping hot all the way through, and enjoy!

13. French fries

Perhaps one of the most difficult leftovers to bring back from the dead, microwaved French fries are a one-way ticket to a culinary disaster. But don't despair, simply head to the hob to revive those potatoes.

Instead, put a little olive oil in a non-stick pan, set the heat to low, and toss in the fries. Wait for them to be heated through, and you're good to go. All hail the nice and crispy re-heated fry!

14. Nothing

Literally nothing: That's right—one of the worst things you can do with your microwave oven is to turn it on while leaving it completely empty inside. Without anything to absorb the microwaves themselves, they just bounce around and microwave the microwave!

At best, you might get a cracked glass plate. At worst, the waves will damage the magnetron — that is, the heart of the machine, which creates the waves in the first place — beyond repair.

15. Foil pouches

Everyone makes mistakes — that’s why pencils have erasers. But just because your aluminum foil has been converted into pouch form, that doesn’t make it any more safe for the microwave.

Capri Sun drinks, for instance, will still have you seeing sparks if you choose to heat them. It's a weird idea to zap a Capri Sun anyway — wouldn't you prefer it cold? — but still, don't do it!

16. Dry sponges

Microwaving sponges can be a great way to sterilize them. After all, they’re one of the most bacteria-ridden items found in most households, carrying all sorts of harmful microorganisms — including E. coli and salmonella.

But if you do, make sure to wet them first: a dry sponge is a fire waiting to happen. Just heat the fully-saturated sponge on high for one minute, and it should be as good as new.

17. Grapes

Have you ever wanted to see your microwave burst into flames? No, we thought not. In that case, it’s probably a good idea to never try putting grapes into it, then.

That’s because the skin of a cut grape heats up so quickly that it erupts into fire, and if the conditions are right, it can even produce the fourth state of matter — plasma.

18. Most takeout containers

Who doesn't love a fuss-free lunch made up of last night's leftovers? Stupid question — the answer is everyone. Just be wary of also re-using the containers the food was delivered in.

Before re-heating, it’s always best to transfer the food into proper Tupperware. Unfortunately, the majority of plastic takeout containers aren’t suitable for microwaves, as, when heated, harmful toxins can seep from them into your food.

19. Porridge

Microwave cooking porridge is a fine art. Too long and you end with a rock-hard bowl of gruel. Too little and you're left hungry while you wait for the milk to absorb. If you succumbed to eating something else while you wait, there's a trick for re-heating that even Goldilocks would surely approve of!

Instead of returning to the potential pitfalls of the microwave, opt for the stovetop instead. Take whatever oats you have left, mix them with a splash of milk or water for moisture, and use gentle heat to revive the porridge back to its former glory. Add peanut butter for an indulgent treat.

20. Fine china

Unsurprisingly, fine china is best kept out of the microwave. After all, chances are it was created before “microwave safe” was even a necessary term. And let’s be honest, is it really worth risking that vintage, and no doubt expensive, crockery?

Quite simply, if you choose to nuke the "good cups," it will decrease their value at best, and completely ruin them at worst. Take our word for it — you’re better safe than sorry with this one.

21. Quiche

In the event you're stuck with a ton of leftover quiche, don't be tempted to pop your egg pie into the microwave. Sure — you'll get something hot to eat in a matter of minutes. But will it be a delicious slice of quiche? Absolutely not.

Microwave heating the combination of egg and pastry almost always result in a soggy slab. For the best texture, sprinkle a little water on the portion, wrap the whole thing in foil, and heat it in the oven for 15 minutes at 375 degrees instead.

22. Lasagna

No matter how much you love this stacked-and-stuffed pasta dish, it's almost impossible not to end up with a bit left over. Who can eat a family-sized platter solo, after all? Instead of microwaving those leftovers — which will end with a meaty mush — turn on the oven instead.

Add a little fresh sauce and cheese on an individual slice and bake it at 400 degrees for 15 to 20 minutes. Out of sauce? No problem! Simply add a few drops of water to revive the slab, and reheat in the same way as stated previously.

23. Light bulbs

Sure, you probably don’t go around putting light bulbs in microwaves very often. But just in case the thought has ever crossed your mind — you know, just to see what would happen — then you should be aware of the consequences.

Microwaving a light bulb can release toxic chemicals into the air, including lead and mercury vapor. Not exactly what you want near your food. Or anywhere else, for that matter!

24. Steak

Unless you're already a card-carrying member of "Club For Monsters Who Like Well-Done Steaks," microwaving beef-based leftovers is a surefire way to straight-up ruin your meat. Step away from the microwave! Instead, keep your steak juicy by placing thin slices of it in an oiled pan and sautéing them until they're warmed through.

The trick here is a short burst of high heat. Either mix through a stir-fry, add to a sandwich, or simply enjoy as a beefy treat all on its own. Just no microwaving, okay?

25. Fish

Avoid being that guy at the office who chucks his fish into the microwave and inevitably stinks up the whole joint. In fact, leftover fish is probably best left far, far away from the microwave altogether.

The best way to enjoy seafood the second time around is to give it a new purpose. You could flake it and add it to a salad, or mix it up with some leftover mash to make fish cakes.

26. Toothpicks

Ever wanted to throw the rule book out of the window and turn your microwave into a science experiment? Well, microwaving toothpicks is a surefire way to do just that! However, heating the handy picks is actually quite dangerous.

You’re essentially creating tiny balls of lightning that will bounce around your microwave oven. And the damage it can do to your appliance probably isn’t worth the few seconds of entertainment, either.

27. Breast milk

Heating breastmilk kills any harmful bacteria that could be ingested by the baby, but warming bottled breast milk in a microwave is basically an all-round bad idea. Typically, parents carefully sterilize the milk by placing the bottles in warm water in the sink — but never in the microwave.

Not only is there a chance that the bottle might explode, but microwaves don't heat liquids evenly, which increases the risk of accidental scalding. What's more, microwaving can also lessen its nutritional value.

28. Mashed potatoes

Want to avoid reheated potatoes that get all crusty? Similar to the way you might melt chocolate for a cake, simmer water in a pan, and then put a bowl of your mashed 'taters over the hot, steaming water.

Add milk, and more butter, and stir as the steam gently reheats the potatoes. This should dodge any of those unwanted crusty edges. Alternatively, lean into the crust by using the leftovers to top a pie.

29. Pasta with a cream or oil-based sauce

Not only does microwave heated pasta rarely hold it's texture, if this dish gets too hot, you'll have one mighty big mess on your hands — in other words, a leftovers disaster.

Avoid the microwave, which will overheat the sauce and render your pasta fit for nothing but the bin, and simply toss it in a pan on medium heat. Don't forget to add a dash of extra cream or oil while it cooks to keep things moist.

30. Stainless steel travel mugs

Yes, it’s more metal in the microwave and should probably be obvious. But because a travel mug is intended to deal with high temperatures, some of us might not think twice about chucking it in the microwave for a blast.

Unfortunately, the steel will reflect the microwaves rather than absorb them, which could harm your microwave, along with the mug.

31. Fish and chips

Here's the ultimate reheat challenge: restoring not one, but two different foods to their former selves. We've already covered what not to do to french fries, and the same goes for this traditional British dish. But what about the fish?

There really is no challenge! So long as you avoid the microwave, that is! It's as simple as throwing the whole dish on an oven-proof tray and baking at 400 degrees for ten minutes.

32. Non-sauced noodles

Are you a meal-prepper who makes a massive pot of noodles to start the week? If you answered yes, then please don't microwave them! Similar to pasta, noodles tend to dry out when left in the refrigerator. And yep, you know the drill by now — the microwave will only make that dryness even worse.

Instead, just pop a serving of the noodles back into boiling water. In a mere 40 seconds, you'll have a steaming plate of goodness that's been reheated the right way.

33. Casserole or chicken pot pie

Both casserole and chicken pot pie are undisputed comfort foods. However, both have the ability to go from delicious to disgusting in the blink of an eye. As both are first cooked in the oven, it's back there you should head to restore them to all of their comforting glory.

For casserole, put a splash of water on what's left, cover it with foil, then cook it at 350 degrees. The dish is successfully reheated when the middle is piping hot. And for pot pie, just bake it at 400 degrees in an oven-safe casserole dish for 20 minutes.

34. Roasted potatoes

If you place it in the microwave, a roasted potato would be piping hot, but soggy. Keep leftovers crispy by adding a drizzle of oil and re-roasting them at 400 degrees for 15 to 20 minutes.

For the best results, start off by covering the spuds in foil until they're heated through. When they're warm, remove the cover and let them crisp. Did you also have leftover gravy? Why not create a little poutine-inspired dish?

35. Plastic wrap

It shouldn’t be news to you by now that plastic and microwaves generally don’t mix, but plastic wrap can be particularly hazardous if it’s touching the food it's covering while being heated.

When exposed to the high heat of a microwave, plastic wrap can easily melt, sticking and mixing in with your food. If you do need to keep things covered, why not use a plate or piece of wax paper instead?

36. Stir-fry

Let's be honest, microwaved stir-fry might as well be the lining for the bottom of your trash can. No one likes biting into a soggy, oily memory of dinners long gone.

You can reheat it the right way by just recooking it the same way you did the first time around. Throw it back into a pan with a splash of oil, stir, and fry!

37. Scrambled eggs

Although it's perfectly safe to reheat eggs, we have to wonder, is it really worth it? We have to be the bearers of bad news here: leftover scrambled eggs will forever taste bad. Still, if you're fresh out of options — and eggs — there is a way to improve on the spongy mess that will come from microwaving them.

Heat a little butter or oil in a pan, and once it's melted, add the eggs. Be sure to keep them moving and wait for any liquid to cook off before serving. You could also mix through some fresh ingredients to help improve the flavor further. Our favorites are sundried tomatoes, feta, scallions, or smoked ham.

38. Pizza

Were there to be an eighth wonder of the world, it would be pizza. As good hot as it is cold, it's the ultimate leftover food, but it too should be kept away from the microwave. If you aren't in the mood for a chilled slice straight from the fridge, you have a few options. The easiest option is to drizzle the pizza with a little olive oil before placing it into a preheated oven.

The same finish can be achieved with an air fryer, too. For those seeking an extra crispy crust, head to the stovetop. Add the slice to a hot, buttered, pan. Then, cover everything with a lid for 30 seconds — or until the cheese has melted and everything is warmed through.

39. Broccoli

Ahh, Broccoli... The stuff of childhood nightmares gone by. And we can guess why! Those traumatized tots' parents must have been microwaving the life out of those florets. Zapping broccoli not only takes away any satisfying bite that might have been there, but it removes almost all of its nutritional benefits, too.

If you don't want to ditch pre-cooked broccoli that hasn't been used up, opt to steam it instead. It will retain far more of its nutrients, and not end in a soggy, green mess. Alternatively, you could chop the florets into smaller pieces and add them to another dish. Pasta sauces, stir-fry dishes, and pies are all candidates for leftover broc.

40. Chicken

When you reheat chicken, the proteins within it alter considerably. Combine that with a microwave that doesn’t necessarily reheat foods evenly throughout, and you’re left with all the ingredients for an upset stomach. If you want to avoid digestive problems, then, you’ll want to reheat it in the oven or air fryer, or even on the stove.

Whichever way you choose, take extra care to make sure the meat is evenly heated right the way through. Alternatively, you could eat it cold in something like a sandwich or salad.