Almost everybody has one in their homes, and their convenience is unmatched, but today we are asking ourselves, are microwaves really safe to use?

It has been rumoured for years that microwaves can zap the nutrients out of your food, and their use of radiation has raised many questions about their safety. Thankfully we can tell you right now that the majority of these concerns are rather baseless, but we will still explore why a lot of them still exist today, and give you the science behind why you have absolutely nothing to worry about when using a microwave to heat up your dinner!

How were they invented?

Using microwaves for heating food was actually discovered by accident! A man called Percy LaBaron Spencer was an engineer working on magnetrons (vacuum tubes that create microwave radiation) and found a way to more efficiently manufacture them, meaning that instead of producing 17 per day, over 2600 were produced each day instead! It was when he was testing these magnetrons when he discovered that a bar of chocolate that he was keeping in his pocket had completely melted (or so the story goes!). 

After this discovery, Spencer was understandably excited to find out if microwave power could be used to heat other foods, testing the invention on raw popcorn kernels and an egg. He learned that the microwaves produced by the magnetrons did cook all manners of food (with the raw egg exploding as a result of the microwave power!). He went on to create a metal box to trap the microwaves into in order to concentrate them on the food and avoid them spilling out (as they cannot travel through metal) and learned that this invention heated food considerably faster than the average oven. In 1945 he filed a patent for the microwave and the rest is history!

The public were initially reluctant to embrace the microwave, but as the technology improved they became more accepted, and were widely used in the restaurant and catering industry. It meant that chefs could make meals ahead of time and store them to be reheated, eliminating a lot of waste. A whole host of other industries also utilized the new microwaves for their own needs, including using them to roast nuts and coffee beans, and removing shellfish from their shells! They became a staple in homes by the end of the 1970s, becoming even more popular than the dishwasher. 

The Myths

There are plenty of myths surrounding the safety of microwaves, largely due to how they were discovered. Today we are going to bust a lot of them and ensure that you know all of the facts around this handy household appliance.

The dangers of radiation

As we just discussed, microwave ovens do use radiation in order to warm up food (classified, funnily enough, as microwave radiation). Immediately for a lot of people the word radiation conjures up images of nuclear bombs and deathly disease, so it’s understandable that some are hesitant to trust the radiation that the microwave produces. However, radiation actually exists in many places, and is usually absolutely nothing to concern yourself over. The radiation in microwaves is low frequency electromagnetic radiation, and is the same type that your tv satellite, radio and even light bulbs use! We are exposed to these low frequency forms of radiation daily from numerous sources and they are completely harmless to us. 

Now I hear you ask, “but if it’s radiation, why doesn’t it make my food radioactive?”

The answer is simple: In order for something to be classified as radioactive, it needs to release ionizing radiation, which is impossible for microwaves to do. Due to their wavelength, microwaves are classified as ‘non ionising’, which means that unlike ionising radiation, they are unable to destroy atoms and break chemical bonds, and are only able to excite them (cause them to move about at a higher frequency, thus making things to heat up).It is ionising radiation that is produced by things like nuclear reactors, X-ray tubes and the sun that can be radioactive and therefore dangerous, as they break down bonds and damage our DNA, as well as causing cells to mutate (causing cancer).

So the takeaway is, if you do things like listen to the radio or switch on lights in your house, you're putting yourself in no more danger using a microwave.

How can they heat food without hurting me?

Microwaves heat up our food by causing the water molecules within the ingredients to vibrate, which creates heat, and renders your meal ready to eat! As previously mentioned, this doesn’t mean that your food becomes radioactive, as all of the radiation is converted into heat when absorbed into your food. 

“But if microwaves only produce normal heat, why are they so much faster at cooking food than ovens?”

The answer to that question is that microwaves are much more efficient than the average oven, as they don't waste any energy heating the entire cooking space due to only being able to transfer their microwave energy into heat within water molecules. Therefore they are able to concentrate heat solely on your food, meaning that you can enjoy it faster! 

The only way that a microwave could actually hurt you would be if you were inside one! Because microwaves are trapped by the metal box of the microwave, they are unable to escape and heat up the water molecules that exist within the human body. Not to mention that the very few that may escape (for example through the glass door) would be pretty much harmless to us as they are not concentrated. However, if you do have any concerns, studies on the effect of the microwaves that escape the microwave oven have shown that by standing 2 feet away compared to 2 inches away, you can reduce the levels that reach you by one hundred times. It is important to note however that manufacturers of microwaves have to stick to strict guidelines when it comes to safety, being required to line the doors with a metal mesh to prevent the leaking of microwaves, and to use measures to ensure that it isn't possible for the oven to produce microwaves at all when the door is off the latch. 

So really, you don’t have to worry about your microwave cooking more than what you put inside it!

Zapping out nutrients

Okay so microwaves may not be little boxes of killer radiation, but there is still a popular belief that they can ‘zap’ the nutrients out of any food that is heated up inside them. The truth of the matter is that (for the most part!) microwaves don’t kill any more nutrients in your food than other cooking methods. In some cases, they actually allow you to preserve the nutrients in your food more efficiently than other, more conventional methods! Let’s dive into why:

Because microwaves have considerably shorter cooking times than conventional ovens, overall more nutrients are able to be preserved! Usually nutrients are lost the longer that the food is cooked for, for example Vitamin C is preserved significantly better in food cooked in the microwave compared to a normal oven.

Whenever we boil our vegetables, we are actually robbing them of a whole bunch of their nutrients! This is because the extra goodness is stripped away and lost in the cooking water, which is then drained away, along with those precious nutrients. The popular superfood broccoli is one common victim to this, with it’s sulfur-containing compound glucosinolate being lost when it is boiled (and along with it, the cancer fighting properties that the compound contains!). In comparison, when broccoli is microwave steamed it holds onto considerably more glucosinolate, as well as a whole host of other nutrients!

Therefore, whilst it’s true that some nutrients are inevitably lost during microwave cooking, it is usually no more than would be lost during regular cooking, and in fact using a microwave has the ability to preserve those nutrients that would otherwise be lost by using other methods. So unless you usually live on a completely raw food diet, you have absolutely nothing to worry about when it comes to microwaves and nutrients!

Your microwave and plastic

Plastic containers are often used for ready meals and other microwavable foodstuffs, this is because it is easy for the microwaves to pass through these materials in order to heat up your food. They themselves don’t actually become heated by the microwave, however they can become super hot as a result of the food within them being heated up. This is one reason why some plastics aren’t safe to be used inside microwaves, as the heat from the food can be enough to melt them, which at best can cause a nasty mess for you to clean up, and at worst can cause you some really nasty burns!

The biggest existing microwave danger that is backed up by research lies within microwaving some plastics. Plastics that contain the chemical BPA are not advised for microwave use, as when they are warmed up they can start to melt and therefore the toxic chemical can leach into the food or drink that you are cooking. BPA has links to numerous health issues, including neurological issues like Alzheimer’s, as well as other problems such as asthma, type 2 diabetes and cardiovascular disease. Therefore we recommend always checking the packaging of anything that you put in the microwave that you intend to consume to make sure that there aren’t any dangerous nasties in there!

The Takeaway

I really hope that we’ve been able to ease your minds a little bit here today on the subject of microwave safety, as it really is an amazing tool that can allow people to enjoy high quality, yummy food no matter how busy they are, and gives us all the gift of time in our otherwise hectic lives.