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Are negative ions good for you?
Normally I'd dismiss such a question out of hand.
In fact that's exactly what I did when a friend brought
it up about a month ago. But he was insistent he said no this is for real
there's science behind it.
And so I looked into it and I found this.
There are literally hundreds of published peer-reviewed scientific studies on the
biological effects of ions.
It's a body of research that begins about a century
ago and continues to the present day.
And this is just a fraction of it.
Now these studies aren't just about any old ions they're about atmospheric ions or air
ions. And although the results are not uniform, they all begin with the premise
that positive ions make us feel bad and negative ions make us feel good.
So in this video I want to get to the bottom of this.
These are Himalayan salt lamps.
With the heat from the light bulb, it releases negative ions into the air and of
course negative ions are what you breathe in and produce the serotonin in
the body and in serotonin is like the primary neurotransmitter in your whole
body and all living things and that's what makes you feel good...
awesome.
Can I jump in here for a second. When I first heard all this business
about atmospheric ions, my first thought was 'why should we expect there to be
many ions in the atmosphere at all?' I mean to recap, an ion is just an atom or
a molecule that has gained or lost an electron. If it loses an electron it's a
positive ion. If it gains an electron it becomes a negative ion. But here's the
thing: unlike charges attract. So moving about in the atmosphere I'd
expect the positive and negative ions to find each other and then BOOM they're
back to being neutral.
However, as it turns out there are some processes that
are constantly generating atmospheric ions.
For example cosmic rays. These are
highly energetic particles from across the universe that slam into our
atmosphere and transfer their energy to the air, creating ions in the process.
Cosmic rays are thought to create around 500 ions per cubic
centimeter at ground level. In fact they're the most significant source of
ions generated over the oceans.
But here on land there are other sources of
ionization, things like natural radioactivity.
There are these long-lived
isotopes of uranium and thorium and their decay products that can spit out
highly energetic particles in the form of alpha, beta and gamma rays.
These ionize the air and they vary widely from place to place but they can contribute
hundreds up to many thousands of ions per cubic centimeter.
If you were to recommend one of these to me that like has the most negative ions, er, which one
do you think?
I would just go for which one's hottest. -yeah?
Because it's the heat from the lightbulb that creates the heat, which makes the reaction in the salt.
Got it.
Wow! This one's great. Yeah? This would just be perfect
And then you have thunderstorms. Each lightning strike generates copious
amounts of ions.
Perhaps one of the more surprising sources of negative ions is waterfalls.
As water droplets collide with each other or with wetted surfaces
with high velocity, the water molecules create this electrified spray with
negative ions that can be transferred to the air around it.
Depending on your distance from the waterfall, ion levels can reach tens of thousands of ions per
cubic centimeter. And the same effect occurs with ocean waves crashing on shore.
Hello! Hi Derek, how are you?
Good, Can I give you that? Sure.
So what I want to know is how many negative ions are there coming off that lamp when it's on?
We have a technique involving mass spectrometry that measures negative ions coming off
of solids and so we can give it a try.
Are you an ion expert? I've been studying
ions for 55 years. Whoa
And have written hundreds of papers on all
aspects of ions.
So this is my salt lamp. it's meant to give us lots of negative
ions. Can you tell me whether it's giving us some negative ions?
We're gonna have a look and the thing we're utilizing here is that the inlet to this mass
spectrometer is at atmospheric pressure and if there's ions there we'll be able
to detect them. So this is like.. is it is it kind of like an electronic nose or
something for ions? sniffs the ions. - You could think of it as a nose for ions. Yeah, yeah, sniffs the ions. -OK
The lamp is next to the ion sampling cone. I mean it's not on yet but we'll see
if there's any ions coming from it. -No so this display here this would be this
is our mass to charge axis here so how how heavy they are in molecular
weight essentially and if there's ions being formed we're gonna see some signal
on this screen. -There'd be like some peaks? Some peaks, yeah
Now does it need to warm up?
er -I think that's the idea, yeah.
Now there are some places that do naturally
have lower concentrations of ions, namely the interiors of houses and businesses.
Because these structures provide some shielding from the cosmic rays and from
the natural radioactivity. Plus if you have metal ducting and air
conditioning, well some of those charged ions will get stuck in the ducts
so typically levels inside homes and businesses can be as low as around 100
or 200 ions per cubic centimeter.
Ion concentrations are also typically lower
in polluted areas, in big cities or around factories. And that's because the
ions actually cling to those pollutants or the aerosols and so they
don't live as long in the atmosphere.
So the assertion that we live in
environments with fewer ions than our ancestors is true.
If you're thinking that you feel better around waterfalls and oceans and after
thunderstorms than you do in polluted cities or around big factories, well
maybe that's the reason why scientists have been studying the effects of
negative ions on human health for nearly a century.
So let's consider the evidence...
In one study people suffering from seasonal affective disorder were
randomly assigned to one of three treatment groups: bright light therapy
high concentrations of negative ions or low concentrations of negative ions.
They found that both bright light therapy and high-density negative ions independently
produced antidepressant effects, but not low density negative ions.
In another study, participants in a high-density negative ion environment had significantly faster
reaction times and reported being more energetic than those in an ambient air control.
Now if all this sounds too subjective, EEG experiments showed people
exposed to high-density negative ions had a slower alpha wave frequency with
higher amplitude. Participants also reported increased relaxation, alertness,
and improved working capacity. And opposite results have been found with
positive ions. In one study volunteers were exposed to high concentrations of
positive ions for two hours. Symptoms of anxiety and excitement significantly
increased. During the time of exposure serum serotonin levels also increased
significantly. This has even been taken into real-world work environments. An
air ionizer was fitted to the air-conditioning unit in an office
building and periodically turned on and off over 12 weeks. When the ionizer was
pumping out negative ions, workers reported 50% fewer headaches. They also
reported increased alertness, perceived atmospheric freshness, and environmental
and personal warmth. It's feeling it's feeling pretty hot it's been on for an
hour? yeah. So the question is can a salt lamp generate negative ions? let's check
for negative ions? -let's look again
Doesn't look like it.
But, I mean there's not even like a background.
No, there's not... it's just like
it's not even sitting there.
So your conclusion after testing this device is
that it's producing no negative ions. -We're certainly not able to detect any negative ions.
The idea for how these salt lamps are meant to create negative
ions is that water molecules are meant to land on the surface and liberate
chloride ions from the lattice.
But ask any chemist worth their salt and they'll
tell you the energy required to do this is way too high so it just doesn't
happen.
What I find ironic is that there are crystals which when heated will
produce ions. It's just that salt doesn't have the
right crystal structure to make this work. The gemstone tourmaline does.
Those samples are worth many thousands of dollars.
Tourmaline has a structure such that if you heat it and cause it to expand, it will actually
develop an electric charge on the faces of the of the crystal you have
discharges between those faces, breakdown in air and forming ions and that
charge then can get transferred to any organic molecule that's present in the air.
A five degree change was enough to generate ions. -I just find this
extraordinary that there is a crystal, there is a material that you could heat
up and create negative ions. So the reason people wouldn't have tourmaline
lamps is because tourmaline is just really expensive?
okay so we didn't get
any ions off of the salt lamp but I brought something along that I think
might give us some ions. This is an ionic air purifier. When this product was first
launched it sold a two million units. It works by using high voltage to ionize
the air and accelerate those ions to produce the light breeze you can feel
without any moving parts. -Okay I feel a breeze coming out of it
and that should be going into the nozzle? we've got it pointed right at our ion
Inlet so that's good.
We seem to be seeing some ions at the moment and we
have the ionic breeze right up next to the source so.
These are negative ions
these are negative ions.
So if you want negative ions what you need in your
house is not a salt lamp, it's an ionic air purifier.
Before you rush out to buy
one I should warn you that generating these ions produces an unfortunate
by-product:
ozone. So right now we're measuring about 17 parts per billion
actually of ozone. So let's put this up to the front and see whether or not
we see an increase in the amount of ozone.
It's up over 80. So now I think
we're actually at the level of a smog alert.
So you're saying that this device
is creating air that would be considered smog in a city?
I believe so yeah.
That is kind of ridiculous for something that's meant to purify the air. Can you smell
the ozone? -yeah -whoa
Does it trouble you? Oh, it doesn't bother me. I know it and I
want to either leave the lab or turn it off.
What am i smelling for here?
should... -oh yeah the sweet smell -oh yeah -that smell a
little sweet? yeah? yeah -I uh...
A lot of people like that smell but if you smell that it's
not good. so perhaps we should shut this off before we asphyxiate ourselves.
So, generating clean negative ions is challenging but is it even worth
the effort? the research is inconsistent. No significant difference. Evidence for
beneficial effects of negative ions on mood and performance could not be
demonstrated. Of the studies that report significant results,
many have methodological problems in some participants weren't blinded to the
treatment they were receiving. When they were blinded they may still have known
when negative ions were present by the faint smell of ozone. Most of the studies
have very small sample sizes. Plus they surveyed participants on a number
of measures increasing the likelihood that at least one would show a
significant difference, just due to random chance. Ion levels were typically
measured at the source and the distance to subjects was not tightly controlled
nor were the other components of the air so there's no guarantee that
participants were even receiving the expected levels of ions.
A meta-analysis from 2013 reviewing all the prior human ion studies concluded there was quote "no
consistent influence of positive or negative air ionization on anxiety mood
relaxation sleep and personal comfort measures" the only link they found was
between negative air ionization and lower depression scores, though the authors
caution future research is needed to evaluate the biological plausibility of
this association.
Because fundamentally the idea that ions have any biological
effect is implausible.
Consider that in a cubic centimeter of air there are 10 to
the 19 air molecules. So even with tens of thousands of ions the amount is
insignificant, not even one part per billion we're talking parts per million
billion. And there's no reason to suspect the extra electrons would do anything
anyway. I mean in your daily life you are constantly building up charge on
your skin and discharging it through little zaps
say when you touch a doorknob. What would a few more stray electrons
extracellular do? - yeah
Uh, probably not much. So if ions do anything it would likely
be indirectly say by removing pollutants and odors from the air.
The ions would cling to the chemicals and then they would say get attracted to surfaces
surfaces and stick to the surface the chemicals stay on the surface.
So I think ultimately if you are looking for a way to improve your mental and physical
health that is backed by strong scientific evidence, then you should take
a walk outside. I mean you can walk near a waterfall or near the ocean if you
like but the thing that is proven to boost your mood is the exercise.
And as an added bonus you're guaranteed to get some fresh air.
Hey this episode was sponsored by LastPass. You know I remember the very
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Are Negative Ions Good For You?

23 分類 收藏
林宜悉 發佈於 2020 年 3 月 29 日
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