This guide covers standard microwaves, microwaves with grills and combination microwaves. Panasonic leads the branded market but the cheaper own-label sector accounts for 81% of sales by volume.
The ping of a microwave is a familiar sound to us all but for many they still have an unsettling air about them.
As Leo Hickman said:
“Are they braising our giblets as we await the defrosting of the frozen lasagne? Are they stripping all the goodness from our food? No, is the oft-repeated advice from manufacturers, government agencies and the vast majority of scientists who have studied them. Yet their words still haven’t quite dispelled the scepticism that a meal that takes half an hour to cook in a normal oven can be ours to scoff after a three-minute waltz on a dimly lit turntable.”
Microwave cooking can be more energy efficient than conventional cooking because foods cook faster and the energy heats only the food, not the whole oven compartment.
The average microwave uses a fifth of the energy used by a conventional electric oven, according to a study by researchers at Brown University in the US. Where a microwave uses three units of energy to heat a like-for-like meal, an electric oven uses sixteen and a gas oven seven.
But, while microwaves may be particularly energy efficient at heating up or cooking small quantities of food, as the quantity and cooking time increases, the difference in efficiency between a standard oven and a microwave oven decreases.
Also, energy savings in use may be negated by the manufacturing costs of the appliance and the environmental burden of disposal – microwaves often have a shorter life-span than conventional cookers.
Additionally, microwave ready meals can be energy-intensive products in terms of their food miles, the packaging used and the food processing involved. Chris Goodall, in his book ‘How to live a low-carbon life’, estimates that food manufacturing may be responsible for three times as much carbon as home cooking.
It may be better to cook big batches of food, freeze in small quantities, defrost naturally and then reheat with the microwave than to use the microwave for defrosting or for cooking ready-meals for one.
Finally, the microwave clock and standby function may also consume a significant amount of electricity, even when the oven itself is not in use. On this basis, even if a microwave is actually in use for only a few minutes a day, it could be consuming most of its energy when not actually performing a useful task. It may be better to unplug your microwave after using it.
The microwave was invented by US defence firm Raytheon, the world’s largest producer of guided missiles, when developing radar systems. A number of the manufacturers on the table continue to have links to the defence industry. We found links to the military with all the following brands: Beko, Blomberg, AEG, Daewoo, Electrolux, Gorenje, Grundig, Zanussi, LG, Liebherr, Panasonic, Neff, Bosch, Siemens, Servis and Samsung.
Are microwave ovens bad for you?
There is much controversy surrounding microwave ovens and whether the radiation they use can damage your health. A lot of web pages have also been devoted to the effect of microwaves on the nutrients in food. The detractors’ claims against microwaves are persistent, if slightly emotive. We’ll give you some of the arguments on both sides and links to where you can read more.
The science bit
Microwave ovens cook food with waves of oscillating electromagnetic energy that are similar to radio waves but move back and forth at a much faster rate.
Microwaves cause water molecules in food to vibrate, producing heat that cooks the food.
There is no fundamental physical difference between the radiation emitted by mobile phones and cordless phones and that used by microwave ovens, as all are radio waves in the electromagnetic spectrum. Other than frequency, the main difference is power. Phones emit in the order of a few hundred milliwatts to a few watts maximum, while ovens use power levels in the region of 700-1000 watts.
Radiation and cancer
According to the US Food and Drug Administration, microwave energy is changed to heat as it is absorbed by food, and does not make food “radioactive” or “contaminated.”
However, they also say: “...exposure to high levels of microwaves can cause burns, cataracts, temporary sterility but these can only be caused by exposure to large amounts of microwave radiation, much more than the 5mW limit for microwave oven leakage. Less is known about what happens to people exposed to low levels of microwaves. Controlled, long-term studies involving large numbers of people have not been conducted to assess the impact of low level microwave energy on humans. Consumers should take certain common sense precautions [such as not using if door is damaged or open, not standing directly against an oven]”.
According to Cancer Research UK: “Non-ionising radiation has enough energy to move things around inside a cell but not enough to change cells chemically. The radiation from a microwave oven is non-ionising.
“Studies have looked at the possible link between microwave ovens and cancer. Some results suggest there may be a link but other studies haven’t been able to prove this at all.
“Microwaves do produce an electromagnetic field while they are in use. This drops sharply the further you are from the oven and doesn’t last long, as you tend to cook in microwaves for very short periods. Most experts say that microwave ovens don’t give off enough energy to damage the genetic material (DNA) in cells so they can’t cause cancer. Microwaves heat food, but do not make any changes to it that aren’t made in any other cooking method. So they do not make food any more likely to cause cancer.”
Much of the above opinion is supported by the UK Microwave Association, an organisation that represents manufacturers.
However, according to Powerwatch, a non-profit independent organisation with a central role in the microwave radiation debate: “Even when the microwave oven is working correctly, the microwave levels within the kitchen are likely to be significantly higher than those from any nearby cellular phone base-stations.
Remember also that microwaves will travel through walls if the microwave oven is against an inside wall.”
An often stated anti-microwave ‘fact’ is that after some 20 years of research into their use, Soviet Russia banned the use of microwave ovens for heating food in 1976 as they decided that the dangers outweighed the benefit of speed.
Carcinogens were formed in virtually all foods tested. They were allowed again from 1987 when, under Perestroika, Gorbachev allowed many western business pressures to change problematic Russian regulations that did not fit in with “Western Free-Trade” practice. However, we could not verify this ‘fact’ in our online research and no country currently bans microwave ovens.
Cooking in microwave ovens can affect the nutritional value of some foods just like heating foods in any way – boiling, grilling, frying or even steaming – does. A microwave may actually do a better job of preserving the nutrient content of foods because the cooking times are shorter.
The majority of studies on microwaves and nutrition were conducted prior to 2000, probably because the focus of radiation research of late has shifted toward a more ominous threat: environmental radiation from electromagnetic devices, such as mobile phones.
There is concern that microwaving foods in plastic containers can cause toxic chemicals, such as the oestrogen-like compound bisphenol A, to leach into the food from the plastic. Transfer your food into glass or ceramic containers labelled for microwave oven use.
You can get microwaves that have grills as well so you can brown food: microwaves are often criticised for producing pallid food. But you can also get ‘combination microwaves’ which are a combination of a microwave oven, a (conventional) convection oven and a grill. They are space saving and energy efficient if you only need a small size of oven. They are, however, more expensive than solo microwaves.
The following brands make combi microwaves: Whirlpool, Russell Hobbs, Belling, Siemens, LG, John Lewis, KitchenAid, Samsung, Panasonic, Daewoo and Kenwood.
Panasonic operates in a wide variety of sectors producing consumer goods, including owning 51% of Sanyo, but also selling to other businesses (including the aviation sector) and the military.
The company was recently in the news when a worker from a plant in China suffered from aplastic anaemia after working in a toxic environment.
Campaigners Good Electronics reported that a man whose job “involved handling toxic chemicals such as benzene, toluene and xylene” fell ill but the company refused to accept that he was suffering from an occupational disease.
According to campaigners:
“He was told to continue painting DVD cases until further tests revealed that his platelet count was dangerously low; so low in fact that a minor bump could have triggered a fatal brain or visceral haemorrhage. At that point was he hospitalised with severe aplastic anaemia.”
See detailed company information, ethical ratings and issues for all companies mentioned in this guide, by clicking on a brand name in the Score table.
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1 Huffington Post – Is This Common Kitchen Appliance Harming Your Health? 25/8/10 www.huffingtonpost.com/dr-mercola/microwave-cancer_b_684662.html
2 Microwave Oven and Microwave Cooking Overview – Powerwatch,www.powerwatch.org.uk/rf/microwaves.asp 14th May 2014
3 ‘Radiation, microwaves and cancer’ – Cancer Research UK,www.cancerresearchuk.org/cancer-help/about-cancer/cancer-questions/radiation-microwaves-and-cancer, May 2014
4 The Guardian, Is it OK... to use a microwave oven? Leo Hickman, 13th September 2005
5 How to Live a Low-Carbon Life by Chris Goodall, Earthscan 2010
6 MINTEL – Ovens and Microwaves - UK - November 2012
7 Good Electronics, 14th May 2014
This product guide is part of a Special Report on Home Appliances. See what's in the rest of the report.