10 Old Kitchen Hacks That Do More Harm Than Good

Microwaving Food in Plastic Containers

Heat makes plastic release harmful chemicals like BPA so I always microwave in ceramic or glass – that’s a really easy one. Despite many containers being labeled “microwave-safe,” the FDA tested all so-called “microwave-safe” plastic food containers and determined that all plastics, when put under stress (such as freezing or microwaving), leach a small amount of chemicals (such as BPA, see below) into the food. A recent study revealed something even more concerning about supposedly safe alternatives.

A time.com analysis of 455 common plastic products found that 70% tested positive for estrogenic activity, with this number rising to 95% when the plastics were microwaved. Still, studies have shown that even BPA-free plastics can release other hormone-disrupting chemicals like phthalates, or BPA alternatives like bisphenol S and F (BPS and BPF), into foods when microwaved. Even UCSF microplastics researchers have completely changed their habits after seeing the evidence firsthand.

Cooking Omelettes in Ziploc Bags

This viral hack promises easy cleanup by cracking eggs into a plastic bag and dropping it into boiling water. However, the softening temperature on a Ziploc bag is 195 degrees, and water boils at 212 degrees. According to our math, that equals a melted bag and a pot full of watery omelet, which is probably not the time-saver you were hoping for. The safety concerns go beyond just a messy kitchen disaster.

According to Livestrong, harmful chemicals can leach into food when the plastic is boiled, including Bisphenol A (BPA), which has been associated with increased cancer risk. While some bags, like Ziploc, do not contain BPA, other less expensive bags might, and all plastic bags still run the risk of leaching other chemicals into the food. The temperatures involved make this hack particularly risky for your health.

Making Grilled Cheese in a Toaster

Social media is filled with videos showing people turning their toaster on its side to make grilled cheese sandwiches. But rather than any of us trying to verify this, let’s listen to the London Fire Brigade, which has made a public statement asking everyone not to after multiple people complained of their toasters bursting into flames. This was presumably due to flammable cheesy fat dripping down onto exposed heating elements.

The fundamental problem is obvious when you think about it for just a moment. It’s almost as if the device wasn’t meant to be used this way. Beyond the fire risk, this hack completely ignores basic cooking principles – there’s no butter involved, which is essential for proper grilled cheese. You’re essentially making dry toast with melted cheese that could catch fire at any moment.

Opening Wine Bottles with a Blow Torch

This dangerous hack involves heating the neck of a wine bottle with a blow torch to expand the air inside and push the cork out. Experts say this method is not recommended because it steams the wine to create pressure, which can somewhat alter the flavor and aroma, and also could send shards of flying glass into your eyes. The physics behind this method are sound, but the execution is incredibly risky.

There are a whole lot of wacky hacks floating around out there to get this job done sans corkscrew, but none of them seem quite as dangerous as the blow torch method. The theory is that if you heat the bottle just below the cork, the air will expand underneath it and push the cork up and out. However, glass bottles aren’t designed to handle this kind of thermal stress, and the potential for explosive failure makes this one of the most dangerous kitchen hacks circulating online.

Boiling Unopened Cans for Dulce de Leche

The promise of effortless dulce de leche by simply boiling an unopened can of sweetened condensed milk has circulated for decades. Year after year we see this hack pop up as the latest and greatest dessert shortcut, but for decades milk manufacturer Borden, Inc. has been recommending against this practice, advising that it can cause injury due to the heat expansion within the can.

Even if you’re willing to brave the possible explosion, the company also notes that their current cans of Eagle Brand milk are “not designed to withstand high temperatures.” The risk of a pressurized can exploding in your kitchen, potentially causing serious burns and creating a massive cleanup disaster, far outweighs any convenience this hack might offer. But unless you want to risk a sweetened condensed milk explosion all over your kitchen, you’ll probably want to make your dulce de leche another way.

Using Dull Knives to “Be Safer”

Many home cooks mistakenly believe that dull knives are safer than sharp ones, but this old-school thinking is completely backwards. A dull knife isn’t just frustrating – it’s dangerous. You’re more likely to slip and cut yourself when sawing away at a tomato with a blade that couldn’t slice butter. The extra force required to cut with a dull blade makes accidents far more likely.

Professional chefs and safety experts universally agree that sharp knives are actually safer. A sharp knife will make cooking faster, safer and more satisfying. When a knife cuts cleanly through food without resistance, you have better control and need less pressure, reducing the chance of the blade slipping. The outdated belief that dull knives are safer has led to countless kitchen injuries that could have been easily prevented.

Cooking Fish in the Dishwasher

This bizarre hack involves wrapping fish in aluminum foil and running it through a dishwasher cycle. If your dishwasher doesn’t come to a high enough temperature to kill harmful bacteria in foods (145 degrees for fish), you could be at risk of food-borne illness. The temperature control in dishwashers is inconsistent and not designed for food safety.

Since most dishwashers heat to about 130 to 170 degrees, it’s hard to know for sure if your dinner is free of bacteria. Beyond the food safety issues, you’re essentially using a machine designed to clean dishes with soap residue and food particles as a cooking appliance. Is the novelty really worth it? The risk of foodborne illness from improperly cooked fish makes this hack particularly dangerous.

Using Your Phone While Handling Raw Meat

A 2024 study revealed alarming hygiene habits when people use smartphones while cooking. One in three participants didn’t wash their hands after touching raw chicken and before touching a smart device. Three-quarters didn’t wash their hands after handling raw eggs and before handling their smart device. Your smartphone becomes a vehicle for cross-contamination that can spread bacteria throughout your kitchen and beyond.

Only a fifth of participants cleaned their tablets during the activity, and on all occasions, an unclean cloth or a sleeve was used. Dr. Mairead McCann, technical executive at Safefood, said: “This new research is a helpful reminder to home cooks of the potential risks associated with smart devices in the kitchen and the importance of good food safety in the home.” The combination of following digital recipes while handling raw proteins creates a perfect storm for foodborne illness.

Overpacking Your Refrigerator

Overloading your fridge blocks air circulation, which can cause uneven cooling and spoil food faster. This seemingly harmless habit of cramming everything possible into your refrigerator actually defeats the purpose of refrigeration. When cold air can’t circulate properly, certain areas become warmer than others, creating dangerous temperature zones where bacteria can multiply.

The “more is better” mentality with fridge storage ignores how refrigeration actually works. Food in overpacked areas may not reach safe storage temperatures, while items near the back might freeze unexpectedly. This hack of maximizing space actually wastes money by causing food to spoil faster and can put your family at risk of foodborne illness from improperly stored perishables.

Using Black Plastic Containers in the Microwave

Recent 2024 research has revealed a shocking truth about black plastic food containers. Research published in the scientific journal Chemosphere in 2024 reported hazardous flame retardants in 85% of these products that they sampled. Although the article as originally published contained a math error that greatly exaggerated the risks, it is important to understand that flame retardants interfere with hormones, potentially harming sexual function and fertility, damanging the brain, and increasing the chances of developing cancer.

Improper recycling of TVs, computers, and other electronics is exposing consumers to toxins in black plastic products such as black plastic take-out containers, food utensils, toys, and hair products. The problem stems from contaminated recycling streams where electronic waste gets mixed into food-grade plastics. You should avoid all exposure that you can, but especially avoid using black plastic to heat food in the microwave or oven. The heating process accelerates the release of these dangerous chemicals directly into your food.

What seemed like a simple convenience has turned into a major health concern that most people don’t even realize exists.