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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