by Joseph Mercola
Can light affect your health?
In this interview (below
video), Dr. Alexander Wunsch, a world class expert on
photobiology, shares the hidden dangers of light-emitting diode
(LED) lighting that most people are completely unaware of.
In fact, this could potentially be one of the most important video
interviews I've done, as it has enormous impacts - not only on
preventing blindness as you age but it is also a pervasive hidden
risk factor for sabotaging your health.
Largely as a result of energy efficiency, there's been a major
transition to using LED as a primary indoor light source. In this
regard, it worked like a charm, reducing energy requirements by as
much as 95 percent compared to incandescent thermal analog sources
However, the heat generated by
incandescent light bulbs, which is
infrared radiation, is actually beneficial to your health, and hence
worth the extra cost.
There are major downsides to LEDs that are not fully appreciated.
LED lighting may actually be one of the most important, non-native
EMF radiation exposures you're exposed to on a daily basis.
If you chose to ignore these new insights, it can have very serious
long-term ramifications. It could lead to
degeneration (AMD), which is the leading cause of blindness in the
United States and elsewhere.
Other health problems rooted in mitochondrial dysfunction may also
be exacerbated, and these run the gamut from metabolic disorder to
What Is Light?
The definition of light, as applied to artificial light sources, is
Visible light is only
between 400 nanometers (nm) and 780 nm, but "light" is actually more
than just what your eye can perceive.
As explained by Wunsch:
"When we look at
sunlight, we have a much broader spectral range, from somewhere
around 300 nm up to 2,000 nm or so.
For our energy
efficiency calculation, it makes a big difference if we are
talking about this broad natural range or if we are only talking
about… vision performance
[T]he definition that we are only looking at the visible part of
the spectrum [given in the 1930s] … led to the development of
energy-efficient light sources like the fluorescent lamps or
what we have nowadays, the LED light sources, because they are
only energy efficient as long as you take the visible part of
the spectrum [into account] …
[F]or example, [lamps providing]
phototherapy with red light can
be used in medical therapy to increase blood circulation, and
this is a part we are taking away as long as we only look at the
Physicists think that infrared radiation is just thermal waste. But from the
viewpoint of a physician, this is absolutely not true.
last 30 years there have been hundreds of scientific papers
published on the beneficial aspects of a certain part in the
spectrum, which is called
near-infrared or infrared-A."
Near-Infrared so Special?
You cannot feel near-infrared as heat, and you cannot see it, but it
has a major beneficial impact in terms of health.
Near-infrared is what's
missing in non-thermal artificial light sources like LED.
There's also a difference between analog and digital forms of light
sources, and this difference is another part of the complexity. In
essence, there are two separate but related issues: the analog
versus digital light source problem, and the spectral wavelength
Starting with the latter, when you look at the rainbow spectrum, the
visible part of light ends in red. Infrared-A or near-infrared is
the beginning of the invisible light spectrum following red. This in
turn is followed by infrared-B (mid-infrared) and infrared-C
While they cannot be seen, the mid- and far-infrared range can be
felt as heat.
This does not apply to
infrared-A, however, which has a wavelength between 700 and 1,500
"Here you have only
very low absorption by water molecules, and this is the reason
why radiation has a very high transmittance," Wunsch says.
"In other words, it penetrates very deeply into your tissue, so
the energy distributes in a large tissue volume. This
near-infrared A is not heating up the tissue so you will not
feel directly any effect of heat.
This significantly changes when we increase the wavelength,
let's say, to 2,000 nm. Here we are in the infrared-B range and
this already is felt as heat.
And from 3,000 nm on
to the longer wavelength, we have almost full absorption, mainly
by the water molecule, and this is [felt as] heating."
is Critical for Mitochondrial and Eye Health
The near-infrared range affects your health in a number of important
For example, it helps prime the cells in your retina for
repair and regenerate.
Since LEDs have virtually no infrared and an excess of blue light
that generates reactive oxygen species (ROS), this explains why LEDs
are so harmful for your eyes and overall health.
Chromophores are molecules that absorb light.
There's an optical
tissue window that ranges from 600 to 1,400 nm, which means it is
almost completely covered by the infrared-A part of the spectrum. This optical tissue
window allows the radiation to penetrate several centimeters or at
least an inch or more into the tissue.
Chromophores are found in your
mitochondria and in activated water
molecules. In your mitochondria, there's also a specific molecule
cytochrome c oxidase, which is involved in the energy
production within the mitochondria.
(ATP) - cellular energy - is the end product.
ATP is the fuel your cells need for all of their varied functions,
including ion transport, synthesizing and metabolism. Remarkably,
your body produces your body weight in ATP every day.
And, while you can
survive for several minutes without oxygen, were all ATP production
to suddenly stop, you'd die within 15 seconds.
an Important Role in Biological Energy Production
This is why this issue of lighting is so important. Light is a
sorely misunderstood and overlooked part of the equation for
biological energy production, specifically at the
As further explained by
"The cytochrome c
oxidase, which is this [light] absorbing molecule, is the last
step before the ATP is finally produced in the mitochondria.
Here we have this
tipping point where light in a wavelength range between 570 nm
and 850 nm is able to boost energy production, especially in
cells when energy production is depleted…
We know today that many signs of aging, for example, are the
consequence of hampered mitochondrial functioning, and so we
have a very interesting… tool to enhance the energy status in
our cells, in the mitochondria in our cells, and not only on the
surface but also in the depths… of the tissue.
This is one important
aspect and there are hundreds of papers published on these
Infrared saunas are
another magnificent way to nourish your body with near-infrared
light. But not just ANY infrared
Most offer only FAR-infrared and are not full spectrum. Most
also emit dangerous non-native EMFs. So you need one that emits low
or no non-native EMFs.
After searching for a long time I finally found a near perfect one
and hope to have it made to my customized specs in a few months. And
it should be significantly less than $1,000.
So stay tuned for this
and Anti-Aging Procedures Make Use of Near-Infrared
These beneficial effects can be seen in wound healing and anti-aging
procedures where near-infrared is employed.
Since the cytochrome c
oxidase is responsible for an increased production of ATP, the cell
has a better supply of energy, which allows it to perform better,
and this is true no matter where the cell resides.
This means liver cells with more ATP will be able to detoxify your
body more efficiently; fibroblasts in your skin will be able to
synthesize more collagen fibers and so on, because ATP is crucial
for all cellular functions.
Wunsch expands on this
even more in the lecture above.
According to Wunsch, as little as one-third of the energy your body
requires for maintaining the thermal equilibrium comes from the food
you eat. The electrons transferred from the food, primarily the fats
and the carbohydrates, are ultimately transferred to oxygen and
The more near infrared
you get, the less nutritional energy is required for maintaining
That said, a differentiation is in order.
Most of the METABOLICALLY
USED energy does come from food.
But there is a thermodynamic aspect
to it as well.
Maintaining a normal body
temperature (37°C or 98.6°F) involves two
energy production in
your mitochondria from food
photonic energy (near-infrared
radiation from sunlight and incandescent light bulbs) that is
able to penetrate deeply into your tissue, even through
can enter your body and then be transformed into longer
wavelengths in the infrared part.
They are very
important for supporting the temperature level, the thermal
energy level, of our body which is… a very crucial aspect.
A lot of energy
comes in the form of radiation and this is supporting our
thermal balance," Wunsch explains.
The key take-home message
here is that your body's energy production involves not just food
intake. You also need exposure to certain wavelengths of light in
order for your metabolism to function optimally.
This is yet another
sun exposure is so vitally
important for optimal health.
LED lamps are a form of digital non-thermal lighting whereas
incandescent light bulbs and halogens are analog thermal light
"For a color changing
system you have three different LEDs, a red, a green and a blue
LED, and the intensity of these three colored channels has to be
changed in order to achieve different color use, which is
perceived by the eye in the end.
The control of the
intensity output of an LED is realized in a digital manner
because it's very difficult to have a low intensity in many
The dimming of LEDs is realized by a so-called pulse-width
modulation, which means the LEDs switch on to the full intensity
and then they fully switch off, and then they switch on again.
So we have the
constant on and off in frequencies, which are higher than our
eyes are able to discriminate. But on the cellular level, it is
still perceivable for the cells…
[T]his causes a flicker, which is not perceivable for let's say
90 percent of the population. But it's still biologically
And flicker is
something that is very harmful to your [biology]."
You've likely experienced
this if you're old enough to recall the older TVs that had a very
visible and intense flicker.
Modern flat screens do
not have this perceptible flicker, but they're still switching on
and off. Scientists are now trying to develop systems capable of
transmitting information via high-frequency flicker in the LED
lighting to replace the wireless LAN system.
According to Wunsch, this
is a very bad idea, from a health perspective.
"I call these LEDs
Trojan horses because they appear so practical to us.
They appear to have
so many advantages. They save energy; are solid state and very
robust. So we invited them into our homes.
But we are not aware
that they have many stealth health-robbing properties, which are
harmful to your biology, harmful to your mental health, harmful
to your retinal health, and also harmful to your hormonal or
endocrine health," he says.
Unfortunately, the use of
LEDs has been mandated by 'federal policy' in both the U.S. and much
of Europe, in an attempt to conserve energy.
effective in that regard, the biological impact of these bulbs has
been completely ignored, and by mandating them, options have been
the Dangers of LEDs
Understanding how LEDs can harm your health begins with the
recognition that light emitted from an LED bulb is of a different
quality than a natural light source.
Normally, a natural light
source is a black body radiator that gives off all kinds of
wavelengths in a more or less continuous manner.
LEDs are fluorescent lamps, consisting of,
of the blue light into longer wavelengths, thereby creating a
The yellowish light from
the fluorescent layer combines together with the residual blue light
to a kind of whitish light, a large portion of which is an
aggressive blue light.
"Blue has the highest
energy in the visible part of the spectrum and produces,
infuses, the production of ROS, of oxidative stress," he says.
"The blue light causes ROS in your tissue, and this stress needs
to be balanced with near-infrared that is not present in LEDs.
We need even more
regeneration from blue light, but the regenerative part of the
spectrum is not found in the blue, in the short wavelength,
It's found in the
long wavelength part, in the red and the near-infrared. So
tissue regeneration and tissue repair results from the
wavelengths that are not present in an LED spectrum.
We have increased stress on the short wavelength part and we
have reduced regeneration and repair on the long wavelength
part. This is the primary problem… [W]e don't have this kind of
light quality in nature. This has consequences.
The stress has
consequences in the retina; it has consequences in our endocrine
You probably know by now
that blue light in the evening reduces melatonin production in your
But you also have cells
in your retina that are responsible for producing melatonin in order
to regenerate the retina during the night.
If you use LED lights after sunset, you reduce the regenerative and
restoring capacities of your eyes. Needless to say, with less
regeneration you end up with degeneration.
In this case, the
degeneration can lead to AMD, which is the primary cause of
blindness among the elderly.
However, and this is that
most fail to appreciate, LED light exposure that is not balanced
with full sunlight loaded with the red parts of the spectrum is
always damaging to your biology. Just more so at night.
So, to summarize, the main problem with LEDs is the fact that they
emit primarily blue wavelengths and lack the counterbalancing
healing and regenerative near-infrared frequencies.
They have very little red
in them, and no infrared, which is the wavelength required for
repair and regeneration. When you use these aggressive lower
frequencies - blue light - it creates ROS that, when generated in
excess, causes damage.
So when using LEDs, you
end up with increased damage and decreased repair and regeneration.
Are There Any
There's a wide range of LED lights on the market these days.
Some are cool white,
others are warm white, for example. The former emits higher amounts
of harmful blue light. The warm LEDs can be deceptive, as they give
out a warm-appearing light but do not actually have the red
The warmth comes from
masking the blue with high amounts of yellow and orange.
There are also LEDs available with less blue, which are closer to
the spectral distribution of incandescent lamps with regard to the
blue part of the spectrum.
tools to measure it, you won't know exactly what you're getting.
This is in sharp contrast
to an incandescent light bulb, where you know exactly what kind of
light spectrum you're getting.
"With LED, the layman
is not able to tell if it's a tailored spectrum where you have
the blue part only masked by excessive parts of other spectral
regions," Wunsch says.
"There are different
Soraa, for example, have violet
driver LED, not blue… By their technology, the red is a little
bit more emphasized compared to the standard white light
So there are in fact better and worse LED types around. But the
spectral distribution is just one thing…
We are interested in
the R9, which represents the full reds. This information is
sometimes given on the package. You have, for example,
which is the color rendering index of 95 with an R9 of 97 or so.
This is the only sign
for the customer that you have a high level or a high index for
Identify a Healthier LED
So, when buying LEDs, one way to get a healthier light is to look at
Sunlight is the gold
standard and has a CRI of 100. So do incandescent light bulbs and
candles. What you're looking for is a light that has an R9 (full red
spectrum) CRI of about 97, which is the closest you'll ever get to a
natural light with an LED.
Another factor to look at
is the color temperature.
There are two different
kinds of color temperature:
Physical color temperature
Which means the
temperature of your light in degrees Kelvin (K).
This applies to
sunlight, candlelight, incandescent lamp light and halogens.
What this means is that the source itself is as hot to the
touch as the color temperature given.
The sun, for example, which has a color temperature of 5,500
K, has a temperature of 5,500 K at its surface, were you to
actually touch the sun.
lamps have a maximum of 3,000 K, as the filament would melt
if the temperature got any higher.
Correlated color temperature
This is a
measurement that tells you how the light source appears to
the human eye.
In other words,
it is a comparative measurement. A correlated color
temperature of 2,700 K means it looks the same as a natural
light source with a physical color temperature of 2,700 K.
The problem here is that while such a light LOOKS the same
as a natural light, it does not actually have the same
quality, and your body, on the cellular level, is not fooled
by what your eye sees.
On a cellular
level, and on the level of the retina, the majority of the
light is still cold, bluish white, despite its apparent,
Incandescent light bulbs
have a color temperature of 2,700 K whereas LEDs can go up to 6,500
K - the really bright white LED. In this case, the closer
you are to incandescent, the better.
Lastly, there's the digital
component, which is virtually unavoidable no matter what.
To determine how good or
bad a particular LED is:
"You would have to
measure somehow if the LED produces flicker or not.
Two, three years ago,
it would have been much easier because the camera of an older
smartphone was not as high-tech equipped as they are today.
With an old
smartphone camera, when you look into the light source, you can
see these wandering lines, so you can detect if the light source
is flickering," Wunsch explains.
A simpler way would be to
flicker detector, which are available fairly
Another way to determine
the flicker rate would be to use the slow motion mode on your
camera. Record the light source in slow motion mode and check it for
Unfortunately, it doesn't always work.
Some newer cameras and
smartphones have a built in algorithm that will detect the flicker
frequency and change the shutter speed accordingly to improve the
recording, thereby eliminating the interference.
If your camera has this
algorithm, it will not record a visible flicker even if it's there.
I like being on the cutting edge of technology and I quickly
switched out all my incandescent bulbs for LED lighting.
I now realize the
enormity of my mistake, but at the time - going back almost 10 years
now - I was completely unaware that it could have health
Before that, I used
full-spectrum fluorescents, which is equally deceptive, as it is
full spectrum in name only.
I'm now convinced LED light exposure is a very serious danger,
especially if you are in a room without natural light. The
biological risks are somewhat mitigated if you have plenty of
sunlight streaming through windows.
At night, LEDs become a
greater danger no matter whether you're in a windowless room or not,
as there is no counterbalancing near-infrared light.
Personally, I've not swapped all my lights back to incandescent
because they're such energy hogs. But all the lights I have on at
night have been switched to clear incandescent bulbs without any
coating that changes their beneficial wavelengths.
So the take-home message
of this interview is to grab a supply of the old incandescent if
you can and switch back to incandescent light bulbs.
Just remember to get incandescent that are crystal clear and
coated with white to give off a cool white light. You want a 2,700 K
incandescent, thermal analog light source. Actually, fragrance-free
candles would be even better.
Be particularly mindful
to only use this type of light at night.
After sunset, I also use
"It is definitely a
good idea to keep away the short wavelengths in the evening, so
It's also a good idea
not to intoxicate your environment with too much light. We know
that artificial light levels at night have reached insane
The candle, the
intensity of the candle for example, is absolutely sufficient
If you have to read in the evening or at night time, my personal
favorite light source for reading tasks is a low-voltage
incandescent halogen lamp, which is operated on a DC
transformer. Direct current will eliminate all the dirty
electricity and it will eliminate all the flicker.
There are transformers available where you can adjust the output
between 6 volts and 12 volts.
As long as it's
direct current, there is no flicker, there is no dirty
electricity, and you are able to dim the halogen lamp into a
color temperature that is comparable to candle light even.
This is the softest,
the healthiest electric light you can get at the moment," Wunsch
lights are also very energy efficient - up to 100 percent more
energy efficient than the standard incandescent lamp.
Just be sure to operate
it on DC. Incandescent lights, including halogen, can be operated at
both AC and DC, but when operating on AC, you end up generating
dirty electricity, Wunsch explains.
On DC, you get no
electrosmog with a low-voltage halogen.
The following graphic illustrates the differences in color spectrum
between an incandescent light, which has very little blue, compared
to fluorescent light and white LED.
This next graph illustrates the differences between daylight,
incandescent, fluorescent, halogen, cool white LED and warm white
As you can see, there's a
tremendous difference between incandescent and warm LED. While they
may look the same to the naked eye, there's no comparison when it
comes to their actual light qualities.
Looking at the spectral differences between incandescent and halogen
lamps, there seems to be no difference at all.
In order to elucidate
the disparity, Wunsch did some measurements of incandescent and
halogen lamps using his
UPRtek MK350S spectrometer.
The differences are
almost imperceptible, indeed.
How to Make Digital
When it comes to computer screens, Wunsch suggests reducing the
correlated color temperature down to 2,700 K - even during the day,
not just at night.
f.lux to do
this, but I have a great surprise for you as I have found a FAR
BETTER alternative that was created by Daniel, a 22 year old
Bulgarian programmer that Ben Greenfield introduced to me.
He is one of the rare people that already knew most of the
information in this article.
So he was using f.lux but was very
frustrated with the controls. He attempted to contact them but they
never got back to him. So he created a massively superior
alternative called Iris.
It is free, but you'll
want to pay the $2 and reward Daniel with the donation. You can purchase the $2
Iris software here.
OLED screen technology is another development
that may be better than conventional screens.
"[With] the OLEDs
technology, I'm not sure if the color is really stable in every
angle you can look at the display," Wunsch says.
"But definitely, if
you have the screen technology where black is really black, then
you have less radiation coming into your eyes and the OLEDs
technology is able to provide this.
So the high contrasts between the black and white, all the black
areas in the thin-film-transistor (TFT) screen or the standard
screen are not really black.
They are also
emitting shortwave radiation. The OLED screen only emits where
you see light, where there is black on the screen, there is no
This might be
preferable as long as you have no problems with the [viewing]
Your Health and Vision, Stick to Incandescent Lights
LEDs are a perfect example of how we're sabotaging our health with
otherwise useful technology.
However, with knowledge,
we can proactively prevent the harm from occurring. In summary, we
really need to limit our exposure to blue light, both during the
daytime and at night.
So for nighttime use,
swap out your LEDs for clear bulb incandescent, or
incandescent halogen lights that are run on DC power.
I also strongly recommend using blue-blocking glasses after sundown,
even if you use incandescent light bulbs.
modifications, the excessive blue light from LEDs and electronic
screens will trigger your body to overproduce ROS and decrease
production of melatonin, both in your
pineal gland and your retina,
the latter of which will prevent repair and regeneration, thereby
speeding up the degeneration of your eyesight.
"One thing to
emphasize again, it's not the blue light coming from the sun
itself which we should be concerned about.
It's the blue light,
the singular high energy visual light (HEV), which comes from
cold energy-efficient non-thermal light sources.
This is what causes
the problem, not the blue light which comes together with longer
wavelengths in a kind of natural cocktail that has the
beneficial near-infrared spectrum …
The light surrogates from non-thermal light sources, these are
[what cause] problems, and you have to be clever to avoid these
If you want to
make it [safe], stay with the candles, stay with the
incandescents," Wunsch says.
Healthy Light Alternative
Candles are even a better light source than incandescent bulbs, as
there is no electricity involved and is the light that our ancestors
have used for many millennia so our bodies are already adapted to
The only problem is that
you need to be very careful about using just any old candle as most
As you may or may not know, many candles available today are riddled
with toxins, especially paraffin candles. Did you know that paraffin
is a petroleum by-product created when crude oil is refined into
Further, a number of
known carcinogens and toxins are added to the paraffin to increase
burn stability, not including the potential for lead added to wicks,
and soot invading your lungs.
To complicate matters, a lot of candles, both paraffin and soy, are
corrupted with toxic dyes and fragrances; some soy candles are only
partially soy with many other additives and/or use GMO soy.
There seems to be a
strange mind-set that exposure to small amounts of toxins is OK,
even though the exposure is exponential over time!
The soy is non-GMO, is clean burning without harmful fumes or soot,
is grown in the U.S. and is both sustainable and renewable. Also, my
candles are completely free of dyes. The soy in these candles is not
tested on animals, is free of herbicides and pesticides.
It's also kosher, 100 percent natural and biodegradable. All of my
fragrances are body safe, phthalate- and paraben-free, and contain
no California prop 65 ingredients.
The wicks are simply flat
braided cotton coated in a natural vegetable wax and self-trimming,
which reduces carbon build up.
Enjoying a Circle of Life Farms naturally good soy candle and
following the simple burn instructions - located inside the candle
lid - will give approximately 70+ hours of burn time.
Every candle is
hand-poured with love for you to enjoy a cooler, cleaner burn, all
while being kind to the both the environment and yourself. You can
search online healthy candles, but if you like, you can use the ones
I found at
This is not an affiliate
link and I earn no commissions on these candles; I just thought you
might benefit from the ones I now use in my home.