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Healthy You

4 myths and truths about microwaving food

Friday, November 10, 2023 10:40 AM
Tags: wellness

By Ryan Morton

Is your microwave a hazard to your health?

If you’ve scrolled through the internet lately, you may have come across articles claiming that your home’s microwave might just kill you. And even if it’s not going to destroy your life, it will definitely leach the nutrients out of the food you cook in it.

But are any of those claims true?

To help demystify your kitchen and your health, we asked Syeda Farid, MS, RD, LDN, registered dietitian at Swedish Hospital Cancer Center, part of NorthShore – Edward-Elmhurst Health, about four commonly held ideas around microwaves.Which are false and which are true?

Microwaving food

1. True or False: Microwaving food gives you cancer.

Despite people commonly calling it “nuking,” microwaving food will likely not give you cancer, says Farid. This idea likely comes from the fact that microwaves are a form of radiation. However, the radiation used to cook food in a microwave is non-ionizing, which means it does not cause cancer. Simply, the radiation vibrates water molecules together to heat up food. Nothing toxic in that.

As Farid puts it, “even though microwaves use microwave radiation to heat the food, the food is not left with microwaves or radiation after cooking.”

Your health would only be at risk if you were directly exposed to large dose of microwave radiation, which could cause cataracts and skin burns. Thankfully, microwaves have a door to prevent radiation from escaping.

This one is false.

2. True or False: Microwaving ruins foods’ nutritional value.

Contrary to popular belief, you can use a microwave to make highly nutritious meals.

One advantage microwaves have over other cooking methods is their ability to efficiently heat food. The longer any food has to cook, no matter the heat source, the more likely it is to lose nutrients.

One bonus of microwaves is they do not require you to introduce additional variables to your cooking. Compared to boiling in water, where nutrients can leach into the surrounding liquid, microwaves allow food to keep their vitamins and minerals.

Studies have shown that some vegetables lose their anti-inflammatory flavonoid content when microwaved, though recent research has found that the most important factor in nutritional loss is how long you cook food in the microwave. Short stints in the microwave should still preserve most benefits in the food it cooks.

This one is false.

3. True or False: Microwaving in plastic is unsafe.

When microwaving, you should consider the container you’re using to cook your food. Farid notes that microwaving food in plastic materials may lead to additives entering what you will be eating.

Phthalates are one example of chemicals that could end up in your meal. Research has shown that this group of chemicals used to make plastics stronger can negatively affect your hormonal system. Bisphenol is another additive that may be released during microwaving. Studies show this chemical compound can result in increased blood pressure and cardiovascular disease.

To best protect your health, experts recommend avoiding plastic containers in the microwave. If you have a meal that comes prepackaged in plastic, transfer it onto a plate or other non-plastic dish before microwaving.

This one is true.

4. True or False: It is safe to boil water in a microwave.

It may be the quickest way to a cup of steaming-hot instant coffee, but using a microwave to boil water could end in disaster.

The primary concern is that microwaves provide little control over how hot you make the water. Leaving water in the microwave for extended periods can lead to what is called superheating. Superheating occurs when something heats a liquid beyond its boiling point.

Once superheated, any disturbances to the liquid, such as stirring, may lead to an eruption of steam, potentially causing burns.

So, to be safe, avoid boiling water in the microwave. If you must, be cautious about how long you heat the water in the microwave. To be safest, stick to boiling water on the stovetop, say experts.

This one is technically true, but it’s wise to avoid boiling water in the microwave, so let’s go with false.

For more questions about healthy cooking, talk to a dietitian or your doctor.

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