Microwave Ovens. Are they safe? Are they Environmentally Friendly?

It is estimated that 95%  of North American homes have microwave ovens in their kitchen.  According to a recent study 75% of people ranked the microwave oven as “almost impossible/pretty difficult” to do without, second only to the automobile.  I remember the good old days – life in the pre-microwave age – the days when meals were made from scratch using fresh ingredients bought from markets, local grocery, bakers and butcher shops. Food shopping and meal preparation was very time consuming.

I remember visiting my first ever supermarket in the 70’s and wandering the aisles in amazement. Supermarkets quickly spread to most locations, along with developments  in refrigeration, home freezers, and the microwave oven,  came the ready meal and the fast food  revolution.

Prior to these developments, food, cooked from scratch, tended to be eaten when it was ready, or kept warm in a warming oven or with the oven left in low on low. By the time late comers came to the meal it was either dried up and congealed, or stone cold in need of  reheating on top of a boiling pan on the stove, which seemed to take forever. So how was the Microwave oven received?  The speed and convenience of cooking seemed unbelievable at the time.

Gradually people grasped the endless possibilities of microwaved food. No more planning ahead, or waiting hours on end for meals to cook, and no more shrivelled up congealed meals, but freshly reheated when required. Food could be frozen then quickly defrosted. Potatoes baked in minutes and even cakes can be made in them.

My Father was an engineer. He embraced new inventions. I remember watching him wrap a baking potatoe in kitchen paper and set the huge microwave on full power for 10 minutes, in contrast to over an hour of conventional oven baking. He was still smiling with wonder as we ate the still slightly hard potato with less flavour and none of the fluffiness of the oven baked variety!

Others were less welcoming of the microwave oven. They were suspicious of the new-fangled equipment, imagining that the food was being “nuked” or “zapped” with radiation.  Not only would the food be affected, but those rays could be floating around the kitchen and home, with the possibility of causing serious illness,  from radiation sickness, to cancer, or maybe even slowly cooking us.   How could it possibly be safe, let alone  beneficial to use one?  Are these safe to use, or should we dash out and purchase a radiation monitor, and/radiation suit?


What are microwave ovens and are they safe?

“Microwave ovens use radio waves at a specifically set frequency to agitate water molecules in food. As these water molecules get increasingly agitated they begin to vibrate at the atomic level and generate heat. This heat is what actually cooks food in the oven. Because all particles in the food are vibrating and generating heat at the same time, food cooked in the microwave cooks much more swiftly than food cooked in a conventional oven where heat must slowly travel from the outside surface of the food inward.

The same radio waves that cook your food pass harmlessly through plastics, glass, and ceramics. It is this characteristic that keeps plastic plates from melting and glasses from exploding. It is also this feature of microwaves that makes them so energy efficient; they heat only the food and nothing more.

Metals, on the other hand, reflect these radio waves, a characteristic very cleverly put to use in the walls of the microwave such that no waves escape and cook anyone in the kitchen! “



Microwaves are sandwiched between radio waves and infrared light on the electromagnetic spectrum.


Whilst microwaves are absorbed by most food, at this wave length,, microwaves are readily absorbed by most foods. However these particles, called  photons, are do not have enough energy to damage molecules and cause cancer  unlike ultraviolet rays or X-rays.

Read more: https://uk.businessinsider.com/how-do-microwaves-work-2014-6#ixzz3gzgMCwmr

Microwave ovens  are tested for radiation and are monitored for the presence of harmful levels of radiation, and there are guidelines to  limit the amount of microwaves that could leak from an oven over its lifetime. Microwave ovens should be used as directed, and maintained in good order. They are built to not leak, but seals and catches around the door should be in good working condition and the door shouldn’t be warped.  Older models can be checked for leaks. Home radiation meters are not very reliable so take it to be checked if you are concerned.  Some recommend not standing close to a working microwave for long periods, just in case!

As with any appliance it is important to keep it clean.  Here is a tip for eco friendly microwave cleaning, using a lemon , a bowl and a dry cloth or towel.

  • Pour water in the bowl: Measure about a half cup of water into the bowl.
  •  Squeeze the lemon: Slice the lemon in half and squeeze the juice into the water. Drop the lemon halves into the bowl.
  • Microwave for 3 minutes: Place the bowl in the microwave. Microwave on high power for 3 minutes so the liquid comes to a boil.
  •  Let stand for 5 minutes: Do not open the microwave door. The steam trapped inside will help loosen food gunk. Let stand for 5 minutes.
  •  Wipe the microwave clean: Open the door and carefully remove the bowl with the lemons. If your microwave has a turntable, lift it out and wipe it clean. Wipe the inside of the microwave clean starting with the ceiling and the sides. Finish with the floor, sweeping any crumbs into your hand. Don’t forget the door!
  • Cleaning stubborn spots: If you come across stubborn spots that won’t easily wipe away, dip the corner of your dishtowel in the lemon-water and scrub until the spot comes away.



They may be classed as safe but are they eco-friendly?

Microwave ovens are relatively environmentally friendly , in the sense that they use less energy than traditional ovens or stoves, as they cook faster. With that speed comes not only efficiency, but some say the food retains more nutrients than other cooking methods. For meat and vegetables it works like a steamer, maintaining vitamins. Sadly it won’t magically get rid of unhealthy ingredients.  If it leads to a reliance on more processed food, the health benefits will be reduced. The health benefits depend on the type of food being cooked.

Use eco-friendly materials for cooking items rather than plastic which can release harmful chemicals. Be careful not to overheat /overcook food as heat can transfer to the container and in the case of liquids can “super heat” and explode.

Although most microwaves have had a long journey from raw materials, and manufacture process to arriving in a domestic kitchen, they are relatively small items and have many recyclable components such as glass and metal. Look after it well and it will last a long time, but make sure you take to the local recycling center for disposal.

Microwaves can be a green addition to our kitchens. How safe is and healthy is your microwave?  It depends what you do with it. If you are dropping it out of an upstairs window it could seriously harm someone underneath or even kill them.  Similarly if you are reheating processed, salty, fatty, unhealthy food it won’t be good for you either. It needs to be clean and well maintained to work safely.

Whilst  munching on my first microwaved potato, and other microwaved food, I could see it was a useful gadget, but back then I didn’t see it as vital – unlike my cousin who ditched her conventional oven and relied on her microwave oven and a hob to feed her family. However, when recently designing my new kitchen, I of course included one.  They are useful for defrosting, reheating , and speed cooking, and even the occasional cheeky microwave cake in a cup!





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