Can cell phone radiation cause harm?

[ramonegumpert]

Hi Experts,

there are a few types of gsm frequencies eg. 900/1800/1900/2100 MHz.

Is it true that the higher the frequency the more watts consumed?

regards
Ramone

 

[f95toli]

Consumed in what? The phone? Basestation?
In general no, there is no such correlation.

 

[ramonegumpert]

Hi f95toli,

As i know, gsm phones using lower carrier frequency bands are limited to consumer 2 watts whereas phones using higher carrier frequency bands are limited to 1 watt.

This is the basis for my question.

regards
Ramone

 

[berkeman]

Hi Experts,

there are a few types of gsm frequencies eg. 900/1800/1900/2100 MHz.

Is it true that the higher the frequency the more watts consumed?

regards
Ramone

Hi f95toli,

As i know, gsm phones using lower carrier frequency bands are limited to consumer 2 watts whereas phones using higher carrier frequency bands are limited to 1 watt.

This is the basis for my question.

regards
Ramone

It's not so much a "power consumed" issue, it's an allowed transmit power issue. The FCC in the US (and other agencies in other countries) regulate how much power you may transmit in different frequency bands. They do this to prevent unintentional interference between bands, and between different users of the same band in geographically different areas.

 

[sophiecentaur]

That will more likely be related to propagation of signals and reducing interference between units, which is different for different frequency bands.

 

[davenn]

That will more likely be related to propagation of signals and reducing interference between units, which is different for different frequency bands.

the power levels from the handpiece are more related to the saftey standards for EM exposure. generally as you go up in freq the power levels are lowered

1W at 1900MHz is more "dangerous" (and I use that term broadly... Please don't start yet another discussion on EM standards etc) to tissue than 1W at 900MHz.

cheers
Dave

 

[berkeman]

the power levels from the handpiece are more related to the saftey standards for EM exposure. generally as you go up in freq the power levels are lowered

1W at 1900MHz is more "dangerous" (and I use that term broadly... Please don't start yet another discussion on EM standards etc) to tissue than 1W at 900MHz.

cheers
Dave

Is that true (the regulatory part between 1.9GHz and 900MHz)? I wasn't aware of that, but it may be true. Can you please supply a (reliable, scientific, preferably peer-reviewed) link to that? Thanks.

 

[davenn]

Is that true (the regulatory part between 1.9GHz and 900MHz)? I wasn't aware of that, but it may be true. Can you please supply a (reliable, scientific, preferably peer-reviewed) link to that? Thanks.

Im not just referring to cellphones, to any transmission device, you being a fellow amateur radio operator like myself, I would assume you have an awareness of that.

1W @ 1296 is going to cause easier cell dissruption that at 470MHz
as is 1W at 10GHz compared to 1296MHz (1.2GHz)

I know personally, I won't use my hand held radio on 1W with rubber duckie antenna beside my head, on 1296MHz, but am not quite so worried about it at 2m or 70cm even at a higher power level

I know its a real minefield area with lots of arguements both ways even by the so called professionals.
but think about it even from a real basic view, the difference between 1W and 2W from a cellphone isn't going to make any signif difference to other signals services in the near area.
Its all to do with the RF level being directly radiated into the brain a couple of inches away from the antenna.
Its what I have been taught in my field of work, I will, in the mean, time stick with it ;)
haha

cheers
Dave
VK2TDN
active on 40m to 1.2cm almost DC to daylight ;) 47GHz coming soon
actually so passionately active on microwave bands, that ask any of my fellow amateurs and they will tell you "ohh yeah dave ... he believes anything below 1GHz is DC" haha

 

[Jiggy-Ninja]

I've heard that, from a physics standpoint, RF level photons don't have enough energy to disrupt molecular bonds. Increasing the output power just throws more photons out, it doesn't increase the energy of each photon.

Also, from a physics standpoint, the only difference between RF radiation and visible light is frequency. They are all electromagnetic waves. But visible light has a much higher wavelength that radio signals, and therefore much higher energy. If RF radiation is dangerous, visible light should be many times more so.

If you're worried about holding a 1W radio transmitter to your head, 100W light bulbs should have you scared witless.

 

[davenn]

those are some seriously bad assumptions ;)

I've heard that, from a physics standpoint, RF level photons don't have enough energy to disrupt molecular bonds. Increasing the output power just throws more photons out, it doesn't increase the energy of each photon.

yes its putting out more photons, EM energy whatever and that's the point RF penetrates and heats tissue in a way light doesn't
from your reasoning it means that being in a more active gamma ray source doesn't make any difference, is no more dangerous to me, because there isn't any increase in photon energy there's just more photons ??
doesnt wash and i think you would agree with that huh ? :)

Also, from a physics standpoint, the only difference between RF radiation and visible light is frequency. They are all electromagnetic waves. But visible light has a much higher wavelength that radio signals, and therefore much higher energy. If RF radiation is dangerous, visible light should be many times more so.

NO, bad assumption, don't forget we cook things with microwaves, NOT light, it has a DIRECT and measurable effect on tissue and not just at the surface ! RF energy literally boils and bursts the cells

If you're worried about holding a 1W radio transmitter to your head, 100W light bulbs should have you scared witless.

not at all, for all of the previous reasons, for my 240VAC, 100W globe and a freq of 50Hz the worst I am likely to suffer is a bit of radiated IR energy slightly warming the side of my head
the same for a 100W DC voltage powered globe

knock that up to 1GHz or 5GHz etc and you are looking at EM energy that will penetrate my skull and do god knows what damage, even at relatively low power levels with relatively sustained exposures.

I got a nasty RF burn at less than 1 W at 24GHz within a few seconds


Now also let's put this cellphone use into the real world. The majority of us ~ 30 + yr olds are not really at risk, we don't have overly long phone calls and the longer ones are rare.
Compare that to the 10 - 30 yr old age group who spend sometimes hours a day talking to their friends on their phones. its going to be really interesting to see population statistics on head trauma relating to physiological and psychological damage in that age group after 20-30 yrs of that sort of activity


cheers
Dave

 

[ramonegumpert]

Dear Experts,

In short, am i right to say that higher frequency band used means lower radiation from a phone to your skull? And both levels of radiation has no effect on your health since 60watts bulb radiates more energy to us than a 2 watt phone?

regards
Ramone

 

[davenn]

Dear Experts,

In short, am i right to say that higher frequency band used means lower radiation from a phone to your skull? And both levels of radiation has no effect on your health since 60watts bulb radiates more energy to us than a 2 watt phone?

regards
Ramone

NO :) read my comments about the differences between a light globe radiation and RF energy radiation

what they are doing with cellphone handhelds is trying to keen the power level to a minimum level that "hopefully " isn't going to cause any harm... That has yet to be seen only time will tell as in my previous comments

cheers
Dave

 

[Jiggy-Ninja]

those are some seriously bad assumptions ;)

yes its putting out more photons, EM energy whatever and that's the point RF penetrates and heats tissue in a way light doesn't
from your reasoning it means that being in a more active gamma ray source doesn't make any difference, is no more dangerous to me, because there isn't any increase in photon energy there's just more photons ??
doesnt wash and i think you would agree with that huh ? :)

The key there is Gamma ray source. Gamma rays are very high energy photons, and are very dangerous. Standing in a powerful gamma ray source is more dangerous than a weak one, because gamma rays themselves are dangerous.

Light in the ultraviolet range or higher has the power to break the molecular bonds in DNA, which is why it can cause skin cancer. RF radiation doesn't have anywhere near that much power.

NO, bad assumption, don't forget we cook things with microwaves, NOT light, it has a DIRECT and measurable effect on tissue and not just at the surface ! RF energy literally boils and bursts the cells

Microwaves are light, just not visible light. RF radiation is electromagnetic radiation, just like visible light, UV light, infrared, gamma rays, x rays, etc. The only difference is frequency.

Microwave ovens have their radiation specifically tuned to resonate with the natural vibration frequency of water, fat, and sugar molecules and make them vibrate harder, and they throw a couple thousand Watts of energy at it. That's a lot more than most hand held transmitters, and if the frequency is changed slightly, no resonance (and no heating).

Sticking your hand in a microwave oven is a bad idea, but a microwave transmitter likely doesn't have the right frequency for resonance or enough power to appreciably heat your body.

Finally, microwaves do not penetrate, at least not very far. I remember seeing a Mythbusters episode where they stuck a big, frozen chunk of meat in the microwave for 20:00. When they pulled it out, the outside was cooked, but the inside was still frozen.

The military is also experimenting with non-lethal microwave guns. A short blast causes the skin to heat to a high temperature with low penetration. Wikipedia states the the frequency they use is about 94 GHz.

not at all, for all of the previous reasons, for my 240VAC, 100W globe and a freq of 50Hz the worst I am likely to suffer is a bit of radiated IR energy slightly warming the side of my head
the same for a 100W DC voltage powered globe

knock that up to 1GHz or 5GHz etc and you are looking at EM energy that will penetrate my skull and do god knows what damage, even at relatively low power levels with relatively sustained exposures.

My point was the light. Visible light has a frequency around 400 - 800 THz, well over 1,000 times higher than any RF radiation.

If you are worried about RF because of the frequency, visible light should be much, much worse. Yet we can stand all day under lights of all kinds without worrying about the visible spectrum light "penetrating our skulls and doing god knows what damage".

And in my experience (and what I vaguely remember hearing from sources I can no longer remember), RF radiation doesn't penetrate that well. It reflects off of and refracts around things, rather than penetrate straight through them. That's why a WiFi signal goes way down when you shut the door to the room it's in.

High frequency radiation does penetrate skin and can cause damage, which is why you need X rays to see through skin and view bones, and why you need to limit your exposure to it. RF radiation is far too low energy to do that.

I got a nasty RF burn at less than 1 W at 24GHz within a few seconds

I am curious about this, since it goes against my intuition from physics classes.

Now also let's put this cellphone use into the real world. The majority of us ~ 30 + yr olds are not really at risk, we don't have overly long phone calls and the longer ones are rare.
Compare that to the 10 - 30 yr old age group who spend sometimes hours a day talking to their friends on their phones. its going to be really interesting to see population statistics on head trauma relating to physiological and psychological damage in that age group after 20-30 yrs of that sort of activity

I'm 20 and don't even own a cell phone. :tongue:

One must be careful when interpreting data about something that's not fully understood or with a lot of controversy. i remember reading about one study that proved ice cream consumption and polio infection rates were positively correlated. The key there is that ice cream is eaten most in summer, which was also the season with the greatest amount of polio infection.

cheers
Dave

Cheers.

 

[davenn]

The key there is Gamma ray source. Gamma rays are very high energy photons, and are very dangerous. Standing in a powerful gamma ray source is more dangerous than a weak one, because gamma rays themselves are dangerous.

it just gives them the Power to go right through you rather than just a few cm or so into you

Microwaves are light, just not visible light. RF radiation is electromagnetic radiation, just like visible light, UV light, infrared, gamma rays, x rays, etc. The only difference is frequency.
Microwave ovens have their radiation specifically tuned to resonate with the natural vibration frequency of water, fat, and sugar molecules and make them vibrate harder, and they throw a couple thousand Watts of energy at it. That's a lot more than most hand held transmitters, and if the frequency is changed slightly, no resonance (and no heating).

Most microwave ovens in the home are well less than 1000W, mine is only 650W

the thing with handheld transmitters like cellphones and handheld radios is that the RF source is very concentrated. a lot of those antenna have gain that produces a higher effective radiated power, and that concentrated power is right beside the brain!

Sticking your hand in a microwave oven is a bad idea, but a microwave transmitter likely doesn't have the right frequency for resonance or enough power to appreciably heat your body.
Finally, microwaves do not penetrate, at least not very far. I remember seeing a Mythbusters episode where they stuck a big, frozen chunk of meat in the microwave for 20:00. When they pulled it out, the outside was cooked, but the inside was still frozen.

The point is, they don't have to penetrate far a cm or 2 into the side of the head and with regular exposure the damage is done

yeah true, but the side of your or my head ISNT frozen!

And the mybusters were busting the myth that microwave ovens heat/cook an object from the inside out... it was well busted :)
That point doesn't affect this discussion

My point was the light. Visible light has a frequency around 400 - 800 THz, well over 1,000 times higher than any RF radiation.
If you are worried about RF because of the frequency, visible light should be much, much worse. Yet we can stand all day under lights of all kinds without worrying about the visible spectrum light "penetrating our skulls and doing god knows what damage".

you still miss the point ... light ... regardless of its higher freq still doesn't penetrate
the skin for more than maybe a mm or 3

And in my experience (and what I vaguely remember hearing from sources I can no longer remember), RF radiation doesn't penetrate that well. It reflects off of and refracts around things, rather than penetrate straight through them. That's why a WiFi signal goes way down when you shut the door to the room it's in.

A lot of WiFi signals are at 2.4 GHz, the same as the microwave oven!

I am curious about this, since it goes against my intuition from physics classes.

...about the RF burns well there you go, you can't believe everything they tell you in class
I have practical experience! :) or should I be :(
RF, particularly microwave RF energy IS dangerous even at low levels
In days go by when I worked for a national communications company, it was (still is) a total NONO to work on/or near powered antennas on radio towers (dish antennas etc) even tho the majority of these dishes were only receiving less than 5W of power from the transmitter.

Its been recognised for many decades that being in close proximity to even low energy microwave sources is dangerous.

Cheers
Dave

 

[Jiggy-Ninja]

it just gives them the Power to go right through you rather than just a few cm or so into you

The frequency gives it the power to go right through you, not the amplitude. Gamma rays are very high frequency, and its photons are very high energy. RF photons have very low energy in comparison, so they can't penetrate as far.

Most microwave ovens in the home are well less than 1000W, mine is only 650W

the thing with handheld transmitters like cellphones and handheld radios is that the RF source is very concentrated. a lot of those antenna have gain that produces a higher effective radiated power, and that concentrated power is right beside the brain!

Wasn't sure the exact number, i just knew it was pretty big. Point is, microwave ovens have much, much higher wattage than any handheld transmitter.

The point is, they don't have to penetrate far a cm or 2 into the side of the head and with regular exposure the damage is done

yeah true, but the side of your or my head ISNT frozen!

And the mybusters were busting the myth that microwave ovens heat/cook an object from the inside out... it was well busted :)
That point doesn't affect this discussion

You missed the point, the experiment was entirely relevant. Microwave ovens do not cook from the inside out because microwaves do not penetrate very far.

you still miss the point ... light ... regardless of its higher freq still doesn't penetrate
the skin for more than maybe a mm or 3

Visible light and RF radiation are the exact same phenomenon. Just because RF is invisible does not make it magical.

RF has lower frequency than visible light, with less energetic photons, so it should have less penetrating power and be less dangerous, by what I've learned.

A lot of WiFi signals are at 2.4 GHz, the same as the microwave oven!

And much lower power than a microwave oven.

...about the RF burns well there you go, you can't believe everything they tell you in class
I have practical experience! :) or should I be :(
RF, particularly microwave RF energy IS dangerous even at low levels
In days go by when I worked for a national communications company, it was (still is) a total NONO to work on/or near powered antennas on radio towers (dish antennas etc) even tho the majority of these dishes were only receiving less than 5W of power from the transmitter.

Its been recognised for many decades that being in close proximity to even low energy microwave sources is dangerous.

Cheers
Dave

I'm currently in my Communications class, so i'll see what I learn about this stuff then.

And I don't take everything the teachers say for granted. Which is a problem in and of itself, since I can sometimes hold the class up with my ceaseless questioning.

I have a Scientific American article somewhere that says the same things I've been saying. If I dig it up I can give you a reference for it. Might need to dig it up anyway to show in my Comm class.

EDIT: Found it. Oct. '10 issue, Skeptic section, Can You Hear Me Now?: Physics shows that cell phones cannot cause cancer. by Micheal Shermer. It's online at the http://www.scientificamerican.com/article.cfm?id=can-you-hear-me-now". It only mentions cancer, instead of the microwave heating thing, but I still think that shouldn't be much of an issue because of the low power involved.

 

[davenn]

Th
I have a Scientific American article somewhere that says the same things I've been saying. If I dig it up I can give you a reference for it. Might need to dig it up anyway to show in my Comm class.
EDIT: Found it. Oct. '10 issue, Skeptic section, Can You Hear Me Now?: Physics shows that cell phones cannot cause cancer. by Micheal Shermer. It's online at the http://www.scientificamerican.com/article.cfm?id=can-you-hear-me-now". It only mentions cancer, instead of the microwave heating thing, but I still think that shouldn't be much of an issue because of the low power involved.

wonder of you read any of the following comments to that article ?

Sci Am were slammed strongly for releasing such a shoddy piece of so called research

Dave

 

[russ_watters]

wonder of you read any of the following comments to that article ?

Sci Am were slammed strongly for releasing such a shoddy piece of so called research

Dave

You really shouldn't put much stock in those comments. Anyone can post a comment there.

 

[davenn]

You really shouldn't put much stock in those comments. Anyone can post a comment there.

possibily, but on the other hand it still makes you question the total validity of what was being reported

The prob is that jiggy ninja seems to have a real problem separating RF from light. regardless of if they are both photons or not.

Here's something else for him to consider.

Ground penetrating radar commonly uses ~ 400MHz to trade off between good depth and reasonable resolution, depths up to 100m. At 1500MHz depth is greatly restricted to only ~ 10metres max but with greater resolution.
Jiggy, try doing ground penetrating radar with a 100W light globe, what have you got to say for your photons now ? ;) trust me... it aint going to work! RF EM energy penetrates where light doesnt. RF easily penetrates the wall of a building, light wont.

if it can penetrate a wooden or concrete wall easily, how much easier is it for it to penetrate a couple of cm of skin and skull and start heating up things inside when its coming from a concentrated source ?

As I said earlier I have personal experience from RF burns at power levels less than 1Watt
I have worked in the RF telecommunications industry for 30 years. Health effects of RF energy on the body are taken VERY seriously and for good reason ... careless guys have been seriously injured.

look ... if it specifically causes cancer any sort of cancer or not may still be debateable are I won't argue with that. but who knows what effects of long term exposure are occurring even by the low level but concentrated heating effects on brain tissue.

I work on RF from 7 MHz to 47GHz at all sorts of power levels. But as I go up in freq through the uWave bands I become more and more aware of the higher risks from lower power levels.

I pretty much laugh at these clowns with all their paranoia over cell towers etc. anyone with a minimum maths skill and some basic RF/physics knowledge will work out that at distance from an antenna (any RF antenna / freq for that matter) the RF field level drops off rapidly according to the inverse square law... any physical law stating that a specified physical quantity or strength is inversely proportional to the square of the distance from the source of that physical quantity. and that by the time you get 50m or so from an antenna even with a moderate power to it say 50W, typical cell tower. The field strength is very very low.

but with a cellphone the distance is very small, 2-3cm and the EM field at that distance is still quite concentrated.

cheers
Dave

 

[davenn]

The frequency gives it the power to go right through you, not the amplitude. Gamma rays are very high frequency, and its photons are very high energy. RF photons have very low energy in comparison, so they can't penetrate as far.

well my last post blows that theory out of the water ;)

When you figure out for yourself why RF photons with substantially lower energy levels than visible light photons can penetrate solid objects and higher energy visible light photons cannot, then we may be on to something. There is more at play than just the energy level of the photons :)

Dave

 

[davenn]

Have enjoyed our little exchange :) been a lot of fun and hopefully some learning for both of us.
Maybe even given a few other passerbys some "amusement" :)

Thanks lots

Dave

 

[sophiecentaur]

well my last post blows that theory out of the water ;)

When you figure out for yourself why RF photons with substantially lower energy levels than visible light photons can penetrate solid objects and higher energy visible light photons cannot, then we may be on to something. There is more at play than just the energy level of the photons :)

Dave

There are two separate issues about penetration here. Diffraction is a way of explaining the difference. Gamma and Xrays have wavelengths much smaller than atoms so the diffraction pattern will be caused by a number of scattering centres (the nuclei). A large proportion of a beam of Xrays can propagate a long way through the spaces between the atoms before photons are 'stopped' and absorbed by interaction with a nucleus. Radiation of longer wavelengths will have a different interaction with the medium. There are no definable scattering / absorbing centres and the photons interact with the bulk of the material. The depth of penetration will relate to the wavelength and to the actual absorption properties of the substance (resonances). So radio waves will penetrate to the sort of depths that X rays penetrate but the absorption mechanism is different. In the case of high energy radiation, ionisation can occur (each photon will produce one ionation'sworth of damage) but for low energy RF, the only result is heating, which needs considerably more total power before damage is done as a result of heating.

 

[Jiggy-Ninja]

wonder of you read any of the following comments to that article ?

Sci Am were slammed strongly for releasing such a shoddy piece of so called research

Dave

I did not, until just now. I read it in print first, and found the article to link to it.

As Russ mentioned though, comments can be posted by anybody, whether they have the credentials or knowledge. Kind of like here, but at least forums allow for back-and-forth discussion, unlike article comments. Just cherry-picking the dumbest one out of the first two pages of the comments:

The author talks about photons, as if most people used their mobile phones primarily as flashlights. Why is that?

Amidst the mass of plausible-sounding biology stuff that I don't fully understand, there is this one:

Mr Shermer does not even mention the fact that numerous studies of mice and rats, who were deliberatly bred to be to be susceptible to various cancers, have shown no increase in any cancer even when they were exposed to cell phone microwave radiation 24 hours a day for their entire life spans.

I wonder if I could fin one of those, could be interesting to read.

Though, I have a slight feeling that if you substituted the article with one about why vaccines don't cause autism, you'd get remarkably similar comments.

A number of people brought up the point that some researchers have proposed plausible mechanisms about how low energy non-ionizing EM radiation can be detrimental to health through things like affecting proteins and the like. My (only slightly uninformed, I think) opinion about that is to remember that aether was once proposed as the medium through which light waves propagated. And all of us here should know what happened to that. Just because it might be a mechanism doesn't mean it is a mechanism.

possibily, but on the other hand it still makes you question the total validity of what was being reported

The prob is that jiggy ninja seems to have a real problem separating RF from light. regardless of if they are both photons or not.

I have a problem because RF and visible light are both electromagnetic radiation, and aren't that different from each other. Visible light is just one small subsection of the broader EM radiation spectrum.

Here's something else for him to consider.

Ground penetrating radar commonly uses ~ 400MHz to trade off between good depth and reasonable resolution, depths up to 100m. At 1500MHz depth is greatly restricted to only ~ 10metres max but with greater resolution.
Jiggy, try doing ground penetrating radar with a 100W light globe, what have you got to say for your photons now ? ;) trust me... it aint going to work! RF EM energy penetrates where light doesnt. RF easily penetrates the wall of a building, light wont.

if it can penetrate a wooden or concrete wall easily, how much easier is it for it to penetrate a couple of cm of skin and skull and start heating up things inside when its coming from a concentrated source ?

I did not think of ground penetrating radar. Kinda throws a wrench on my interpretation. I'll hold off on answering that until I better understand it.

As I said earlier I have personal experience from RF burns at power levels less than 1Watt
I have worked in the RF telecommunications industry for 30 years. Health effects of RF energy on the body are taken VERY seriously and for good reason ... careless guys have been seriously injured.

look ... if it specifically causes cancer any sort of cancer or not may still be debateable are I won't argue with that. but who knows what effects of long term exposure are occurring even by the low level but concentrated heating effects on brain tissue.

I work on RF from 7 MHz to 47GHz at all sorts of power levels. But as I go up in freq through the uWave bands I become more and more aware of the higher risks from lower power levels

I have nothing to dispute personal experience with. As I mentioned before, I'm still a student, trying to learn as much as I can.

Health issues can be a really complicated issue that is very hard to understand. For most people, the inner workings of life are pretty much witchcraft. Wasn't Asimov who sad that any sufficiently advanced technology is indistinguishable from magic? I think biology certainly counts there. There are potentially billions (or even more) different ways that something can interact with something else to produce an effect we can't understand.

Even EE isn't free of "witchcraft" elements. Put a dozen electrical professionals in a room and ask them whether AC or DC is more dangerous. The justifications you get for either side will be plausible sounding, but ultimately unquantifiable.

And if you felt that that wasn't enough of a Pandora's Box, ask them whether 120 or 240 mains are more dangerous. Go on, I dare you. :tongue:

A burn though, is not witchcraft, I'll give you that. If it's just heating, I don't think it would be that dangerous. You'd probably get worse from the noon-day sun. I'll have a talk with my teacher about that, see what he says.

Have enjoyed our little exchange :) been a lot of fun and hopefully some learning for both of us.
Maybe even given a few other passerbys some "amusement" :)

Thanks lots

Dave

Same here. Given the sort of career I'm going for (which you can guess from where I hang out), there's nothing better than giving the old science muscles a good work out. Now I just need to start giving the rest of me a workout...

As a closing note, a bit less unscientific and more personal opinion than the previous, it seems like every month some researcher somewhere is coming out with a finding that something or other is potentially bad for your health. Even things like milk. At some point, you either ignore most of it so that you can live a normal, non-paranoid, non-obsessive life, or go completely insane, wearing your tin-foil hat so that the microchips the government implanted during your last physical don't transmit your innermost dirty thoughts.