:confused:
what do you think? I always assumed they were fine .. but having performed a "are microwaves dangerous?" search on google it seems i might have to rethink my cooking habits.
Did you know the has USSR banned them?
apparently the radio waves (radiation) work by causing friction between the food particles which makes them get hot. but it also changes the nutriants etc of the food in the process, so even if you are reheating your homemade healthy food - its still not good for you.
would like to know others opinions....

Try placing a Light Bulb inside your Microwave.

Those things are not safe lol.

If you stick you're head in em I don't think you'd be too well.

Actually, they work by causing the water to molecules to resonate, which makes them get hot. Not sure friction exists on that level.

Microwaves have protective metal shells to keep the waves away from humans. If you don't stand to near then they'll not be harmful.

However if you're on your mobile phone at the time you will be cooking your brain (and that is fact not a joke).

Tim

Originally posted by tim_rutter
If you stick you're head in em I don't think you'd be too well.


Why not, you can't close the door.

it's not radio, it's microwave, hence the name.

It affects water molecules, imparts energy to them and thus they get hot.

U get local hotspots in food due to the penertration of the microwaves and the distribution of water. But the temperatures are no higher than cooking the food in a convential way, so I don't see how it could alter the nutrional content more than normal cooking.

Originally posted by viking
Why not, you can't close the door.

Theres a little microswitch that can quite easily be pressed in using a screwdriver ;)

Originally posted by tim_rutter
Theres a little microswitch that can quite easily be pressed in using a screwdriver ;)

Al have to try that when iv'e had a rake of ale :thumbsup:

Originally posted by tim_rutter
Theres a little microswitch that can quite easily be pressed in using a screwdriver ;)

That's one of those pieces of information you will wish you never knew next time you get really drunk! :D

Originally posted by tim_rutter
... Actually, they work by causing the water to molecules to resonate, which makes them get hot. Not sure friction exists on that level...

Friction is evident at any level so yes this is how the food is cooked. That’s why people used to say Microwaves cook from the inside out, which isn't technically wrong. But we have all tried to heat up a microwave meal, put it in for the allotted 3+ minutes and the outside is the temperature of the sun and the inside more like frosty the snowman’s underpants!

I did hear the British standards are less stringent than the USA's. Also the frequency is very close to that used for wireless networks, so they can cause problems for computers (using a wireless network) when they are working.

The grid on the door of your microwave, behind the glass is set to trap the waves so they can’t escape, works on the same as a faraday cage.

there was once a case where a guy removed the door off his microwave and set it up so he could throw things in and turn it on, it was not quite finished one day when he done it and he got really bad burns on his hand:loopy: :loopy:

This article might interest you

http://darrendixon.supanet.com/microwaveovens.htm#howwork

These are the most frightening parts:

In 1991, there was a lawsuit in Oklahoma concerning the hospital use of a microwave oven to warm blood needed in a transfusion. The case involved a hip surgery patient, Norma Levitt, who died from a simple blood transfusion. It seems the nurse had warmed the blood in a microwave oven. This tragedy makes it very apparent that there's much more to "heating" with microwaves than we've been led to believe. Blood for transfusions is routinely warmed, but not in microwave ovens. In the case of Mrs. Levitt, the microwaving altered the blood and it killed her.

It's very obvious that this form of microwave radiation "heating" does something to the substances it heats. It's also becoming quite apparent that people who process food in a microwave oven are also ingesting these "unknowns".

In intervals of two to five days, the volunteers in the study received one of the following food variants on an empty stomach:

(1) raw milk;

(2) the same milk conventionally cooked;

(3) pasteurized milk;

(4) the same raw milks cooked in a microwave oven;

(5) raw vegetables from an organic farm;

(6) the same vegetables cooked conventionally;

(7) the same vegetables frozen and defrosted in a microwave oven; and

(8) the same vegetables cooked in the microwave oven. Once the volunteers were isolated, blood samples were taken from every volunteer immediately before eating. Then, blood samples were taken at defined intervals after eating from the above milk or vegetable preparations.

Significant changes were discovered in the blood samples from the intervals following the foods cooked in the microwave oven. These changes included a decrease in all hemoglobin and cholesterol values, especially the ratio of HDL (good cholesterol) and LDL (bad cholesterol) values. Lymphocytes (white blood cells) showed a more distinct short-term decrease following the intake of microwaved food than after the intake of all the other variants. Each of these indicators pointed to degeneration. Additionally, there was a highly significant association between the amount of microwave energy in the test foods and the luminous power of luminescent bacteria exposed to serum from test persons who ate that food. This led Dr. Hertel to the conclusion that such technically derived energies may, indeed, be passed along to man inductively via eating microwaved food.

According to Dr. Hertel,

"Leukocytosis, which cannot be accounted for by normal daily deviations, is taken very seriously by hemotologists. Leukocytes are often signs of pathogenic effects on the living system, such as poisoning and cell damage. The increase of leukocytes with the microwaved foods were more pronounced than with all the other variants. It appears that these marked increases were caused entirely by ingesting the microwaved substances.

Wow, thanks for the info Zebra. My granny never used to trust microwaves, didn't even want one in the same room with her, now I can see she may not have been entirely wrong.

I remember when we were at school, one of our teachers told us about a woman who washed her poodle and then decided to dry it out in the microwave, to speed things up - DOH! The poodle exploded (at least, that's what our teacher said, although I imagine it would just have died in a slightly less visually impressive way).

I think this was supposed to be a cautionary tale, but of course the only effect it had was to put the whole class into fits of laughter. And probably get half of them looking for small animals to experiment on as soon as they got home.

This jumped out at me too, due to pending twins and if British standards are more lax than American in microwave safety then I dread to think what ours could be doing.

"Microwaves unsafe for baby's milk

A number of warnings have been made public, but have been barely noticed. For example, Young Families, the Minnesota Extension Service of the University of Minnesota, published the following in 1989:

"Although microwaves heat food quickly, they are not recommended for heating a baby's bottle. The bottle may seem cool to the touch, but the liquid inside may become extremely hot and could burn the baby's mouth and throat. Also, the buildup of steam in a closed container, such as a baby bottle, could cause it to explode. Heating the bottle in a microwave can cause slight changes in the milk. In infant formulas, there may be a loss of some vitamins. In expressed breast milk, some protective properties may be destroyed. Warming a bottle by holding it under tap water, or by setting it in a bowl of warm water, then testing it on your wrist before feeding may take a few minutes longer, but it is much safer."

Dr. Lita Lee of Hawaii reported in the December 9, 1989 Lancet:

"Microwaving baby formulas converted certain trans-amino acids into their synthetic cis-isomers. Synthetic isomers, whether cis-amino acids or trans-fatty acids, are not biologically active. Further, one of the amino acids, L-proline, was converted to its d-isomer, which is known to be neurotoxic (poisonous to the nervous system) and nephrotoxic (poisonous to the kidneys). It's bad enough that many babies are not nursed, but now they are given fake milk (baby formula) made even more toxic via microwaving."


I can honestly say I rarely use my microwave and will undoubtedly decrease my use, although I doubt I'll entirely stop. I won't replace it when the time comes though.

Originally posted by serapis
Friction is evident at any level so yes this is how the food is cooked.

I don't want to be pedantic but molecules do not cause friction by vibrating against other molecules. On that level its more to do with molecular attractions and such. Friction is caused by two surfaces rubbing together and is on a much bigger scale - it has no meaning at molecular level. :)

I don't believe in microwaves, nor ghosts, neither. My advice is to go into pernament denial regarding their very existence. Then they will go away. Forever.

Originally posted by Zebra
This jumped out at me too, due to pending twins and if British standards are more lax than American in microwave safety then I dread to think what ours could be doing.

"Microwaves unsafe for baby's milk

A number of warnings have been made public, but have been barely noticed. For example, Young Families, the Minnesota Extension Service of the University of Minnesota, published the following in 1989:

"Although microwaves heat food quickly, they are not recommended for heating a baby's bottle. The bottle may seem cool to the touch, but the liquid inside may become extremely hot and could burn the baby's mouth and throat. Also, the buildup of steam in a closed container, such as a baby bottle, could cause it to explode. Heating the bottle in a microwave can cause slight changes in the milk. In infant formulas, there may be a loss of some vitamins. In expressed breast milk, some protective properties may be destroyed. Warming a bottle by holding it under tap water, or by setting it in a bowl of warm water, then testing it on your wrist before feeding may take a few minutes longer, but it is much safer."

Dr. Lita Lee of Hawaii reported in the December 9, 1989 Lancet:

"Microwaving baby formulas converted certain trans-amino acids into their synthetic cis-isomers. Synthetic isomers, whether cis-amino acids or trans-fatty acids, are not biologically active. Further, one of the amino acids, L-proline, was converted to its d-isomer, which is known to be neurotoxic (poisonous to the nervous system) and nephrotoxic (poisonous to the kidneys). It's bad enough that many babies are not nursed, but now they are given fake milk (baby formula) made even more toxic via microwaving."


I can honestly say I rarely use my microwave and will undoubtedly decrease my use, although I doubt I'll entirely stop. I won't replace it when the time comes though.

caused no doubt by the high temperatures achieved. If you heated food conventionally to the high spot temperatures you find in a microwave then you'd see some of the proteins and enzymes being denatured or changed.
Simply cook it more slowly in the microwave or turn the food more often to reduce the temperatures that hot spots reach.

microwave (radar) ovens are just brilliant for cooking fish.

dangerous? no more than burnt food is dangerous.

sure, if you overcook your food in a microwave you will end up with all sorts of strange byrpoducts, just as if you burned it in the oven

A microwave works by, as has been mentioned ealier, by vibrating water molecules. The more a molecule vibrates, the hotter it is.

The food is cooked by the water in it getting hot.

Put something completely dry in a microwave and it should have little effect.

Originally posted by DanSumption
.......- DOH! The poodle exploded ....

I think this was supposed to be a cautionary tale, but of course the only effect it had was to put the whole class into fits of laughter.

:hihi:

Yep, I can't quite see it being possible to talk about exploding poodles in school without the class erupting!

Originally posted by tim_rutter
I don't want to be pedantic but molecules do not cause friction by vibrating against other molecules. On that level its more to do with molecular attractions and such. Friction is caused by two surfaces rubbing together and is on a much bigger scale - it has no meaning at molecular level. :)

Tim_rutter,
According to my knowledge friction does cook the food ... take a look at this site, it has excerpts from the book The Complete Microwave Oven Service Handbook Especially the bit Friction Produces the Heat That Cooks the Food
http://www.gallawa.com/microtech/howcook.html

Originally posted by serapis
Tim_rutter,
According to my knowledge friction does cook the food ... take a look at this site, it has excerpts from the book The Complete Microwave Oven Service Handbook Especially the bit Friction Produces the Heat That Cooks the Food
http://www.gallawa.com/microtech/howcook.html

I'm really not convinced by that argument. I am definitely being pedantic tho - I am science geek! :D Did a module a uni on friction and as such so know quite a bit about it. I think it would be called something else at a molecular level.

Hmm, if you rub two molecules together hard enough, can you generate enough friction to start a fire? :)

Originally posted by DanSumption
Hmm, if you rub two molecules together hard enough, can you generate enough friction to start a fire? :)

How many cules does the average mole have? Im sure if they had two they could start a fire.

Originally posted by tim_rutter
How many cules does the average mole have?
I think the answer has something to do with avocado's constant.

friction is a physical process where 2 substances rub against each other imparting energy from the vibration into their molecules.
Microwave energy directly excites the water molecules that absorb the radiation and they get hot, which is to say they move around faster.
Same effect as friction, different mechanism for how it occurs.
The energy is then transferred by conduction to the other molecules around the water.

I suppose the exact mechanism for the induction of energy involves exciting an electron into a higher orbit and that decaying, but this is suposition and may be completely wrong.

Originally posted by Cyclone
I suppose the exact mechanism for the induction of energy involves exciting an electron into a higher orbit and that decaying, but this is suposition and may be completely wrong.

I think you're more on the right lines there. THat isn't what happens with friction. Friction occurs on a macro level, where tiny imperfections in the surfaces interact. Heat is generate as these imperfections interact and deform plastically/elastically or break on a macro scale. You can examine this with microscopes. Molecules don't really come into it!

This is getting too deep now.

Originally posted by tim_rutter
This is getting too deep now.
No, not deep enough, what's happening on a sub-atomic level. I'm not happy until we hit quarks, baby!

Originally posted by tim_rutter
Not sure friction exists on that level.


There goes my entire PhD.... :P :D

Originally posted by tim_rutter
I'm really not convinced by that argument. I am definitely being pedantic tho - I am science geek! :D Did a module a uni on friction and as such so know quite a bit about it. I think it would be called something else at a molecular level.

Friction does exist at the molecular level. In fact it is the basis of how some microscopes work (A subset of Atomic Force Microscopy focuses only on the frictional interactions between a surface and an atomically sharp tip :) )

Don't have a clue how microwave cookers operate though ;)

Oops... hit the wrong button and quoted myself :roll: Well, it has been a long day...

Originally posted by TracieJC
Friction does exist at the molecular level. In fact it is the basis of how some microscopes work (A subset of Atomic Force Microscopy focuses only on the frictional interactions between a surface and an atomically sharp tip :) )

Don't have a clue how microwave cookers operate though ;)
Typical bloody scientist, knows all about Atomic Force Microscopy but can't work a microwave :D

Originally posted by DanSumption
Typical bloody scientist, knows all about Atomic Force Microscopy but can't work a microwave :D

I've only just mastered the kettle :P :D

A microwave works because the electric field of the microwave (which is just a plain old electromagnetic wave, somewhere in between visible light, and radio waves) interactions with the dipole moment of water molecules (water has a positively charged end, and a negatively charged end). This causes water molecules in whatever you're cooking to flip and jiggle about - they have more energy.

The molecules are not hotter because of friction....they are 'hot' because they are moving around. When you heat things up in a pan - you make the molcules jiggle about more, when you cool things down in the fridge, you're making them jiggle less - jiggling = heat . (Thats why Beyonce is hot - because she does alot of jiggling)

FRICTIONAL HEATING is a macroscopic effect (as tim says) but a FRICTIONAL FORCE is simply a force that exists perpendicular to the direction of the applied force - this is what is measured in Friction Force Microscopy (AFM). So....everyone's right :)

I'll pm you about quarks later Dan ;) Tracie - put the kettle on pet :hihi:

So, let me see if I've understood this correctly, if there really is any risk inherent in cooking with a microwave, in future we might be able to avoid this by using some other type of cooking, say for example a... Beyoncé-powered oven!!!

Yes, a Beyoncé in every kitchen, it makes perfect sense. Why, I'm getting hot just thinking about it!

hmmm... tres interesant , but, rather drifted off me question.. what about my original point-hm?! health? how come russia banned them?

Beyonce powered LMAO.
Another part of the article link I posted:

In commercial models, the oven has a power input of about 1000 watts of alternating current. As these microwaves generated from the magnetron bombard the food, they cause the polar molecules to rotate at the same frequency millions of times a second. All this agitation creates molecular friction, which heats up the food. The friction also causes substantial damage to the surrounding molecules, often tearing them apart or forcefully deforming them. The scientific name for this deformation is "structural isomerism".

We've all been told that microwaving food is not the same as irradiating it (radiation "treatment"). The two processes are supposed to use completely different waves of energy and at different intensities. No FDA or officially released government studies have proven current microwaving usage to be harmful, but we all know that the validity of studies can be - and are sometimes deliberately - limiting. Many of these studies are later proven to be inaccurate. As consumers, we're supposed to have a certain degree of common sense to use in judgment.

"A basic hypothesis of natural medicine states that the introduction into the human body of molecules and energies, to which it is not accustomed, is much more likely to cause harm than good. Microwaved food contains both molecules and energies not present in food cooked in the way humans have been cooking food since the discovery of fire. Microwave energy from the sun and other stars is direct current based. Artificially produced microwaves, including those in ovens, are produced from alternating current and force a billion or more polarity reversals per second in every food molecule they hit. Production of unnatural molecules is inevitable. Naturally occurring amino acids have been observed to undergo isomeric changes (changes in shape morphing) as well as transformation into toxic forms, under the impact of microwaves produced in ovens.

They probably are dangerous. I have always been told so, anyway! :thumbsup:

Originally posted by Patchy
They probably are dangerous. I have always been told so, anyway! :thumbsup:
Well, that clears that debate up then :)

Originally posted by DanSumption
Well, that clears that debate up then :)

Nice one Danny lad :hihi:

Originally posted by TracieJC
There goes my entire PhD.... :P :D



Friction does exist at the molecular level. In fact it is the basis of how some microscopes work (A subset of Atomic Force Microscopy focuses only on the frictional interactions between a surface and an atomically sharp tip :) )

Don't have a clue how microwave cookers operate though ;)

I stand corrected!

Is heating a chunky bar of chocholate in a microwave dangerous- because the missus totalled our last microwave that way!

Im sure I read somewhere about the microwaves not been able to get into the chocholate bar or something???

Originally posted by Edd
A microwave works because the electric field of the microwave (which is just a plain old electromagnetic wave, somewhere in between visible light, and radio waves) interactions with the dipole moment of water molecules (water has a positively charged end, and a negatively charged end). This causes water molecules in whatever you're cooking to flip and jiggle about - they have more energy.

The molecules are not hotter because of friction....they are 'hot' because they are moving around. When you heat things up in a pan - you make the molcules jiggle about more, when you cool things down in the fridge, you're making them jiggle less - jiggling = heat . (Thats why Beyonce is hot - because she does alot of jiggling)

FRICTIONAL HEATING is a macroscopic effect (as tim says) but a FRICTIONAL FORCE is simply a force that exists perpendicular to the direction of the applied force - this is what is measured in Friction Force Microscopy (AFM). So....everyone's right :)

I'll pm you about quarks later Dan ;) Tracie - put the kettle on pet :hihi:


Phew! Didn't like the idea of being wrong :D

Ok next question, why does metal goes crazy in a microwave?

Originally posted by ANGELUS
Im sure I read somewhere about the microwaves not been able to get into the chocholate bar or something???
Nah, that can't be right, a microwave is by far the best way of melting chocolate, much better than all that faffing about with a bain marie, just ask Nigella!

You have to be careful how you do it though - medium power for 30 seconds, then check every 10 seconds, if memory serves.

Originally posted by ANGELUS
Is heating a chunky bar of chocholate in a microwave dangerous- because the missus totalled our last microwave that way!

Im sure I read somewhere about the microwaves not been able to get into the chocholate bar or something???

Did you take the foil off? (see my last post!) :hihi:

Originally posted by tim_rutter
Ok next question, why does metal goes crazy in a microwave?

because the microwaves induce currents across the metal, the build ups of currents discharge through the air to the case of the microwave. Do it for long enough and it damages your microwave.

a weird microwave thing happened yesterday. I was heating up some milk in a mug for hot chocolate. Ping 2 mins, took out mug of steaming milk and there on the rim was a greenfly looking none the worse for its experience!

I think the really bad nutritional thing with any food is to heat up oils over a certain temperature - anyone know what that temperature is? Anyway it means CHIPS are very bad news - especially from the chippy where they reheat the oil.

They are bad feng shui i know that much! Although i do have one! How would i heat up my wheat bag otherwise!!

Haha, have you seen 'The Fly'? That is what will happen to that greenfly! Find it and kill it before it eats us all!!

Microwave ovens can be dangerous if they are being dropped on to you as u walk past high rise flats - the wattage is less insignificant than the floor level which i t is dropped and it also mattrs not one wit as to whether the door is closed.

My advice would be to avoid all makes and models as high rise flats are a good leveler and anything above floor two is terminal velocity and therefore at full power even though not even plugged in. (Is that energy saving?)

My Dad's friend worked for British Aerospace for years and he refuses to stand in the same room as a microwave when it is switched on and won't eat microwaved food. He won't use mobile phones either.

He might just be a paranoid crazy, but he was working with all sorts of "special projects" at BAe. ;)