Are LED Lights Safe?

Heather Clouse
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Flicker in an LED Light

Most people use LED lights for reading, as nightlights, or for decorative purposes.

While LED lights use less energy and are brighter than other lighting options, they are not without their drawbacks.

Most LED lights produce light by passing an electrical current through a semiconductor material. Depending on the material used, different wavelengths of light are radiated.

Inside the LED there are small parts called semiconductor junctions. There are gas molecules inside the LED that get excited when electricity passes through.

The semiconductor junctions waste some of that energy by radiating it in the form of heat.

Another type of light that is emitted is infrared radiation. You can feel this radiation very well if you put your hand below an LED lamp and feel no heat but still find that it’s uncomfortable to look at the lamp.

LED light is known to cause headaches and eyestrain.

Eye strain can result from LED lights flickering at frequencies that fall within the human nervous system frequencies, or flicker rates.

The rapid changes in light level emitted by an LED, which can occur in a time as short as nanoseconds, can cause painful headaches.

LEDs are not commonly used for home lighting, but they are beginning to gain popularity due to their energy-saving properties.

What Are the Risks of Flicker?

LED lights are cool. Not only do they offer advantages such as low energy consumption, low heat, low maintenance and long life, they are novel and futuristic, too.

That’s why most people love them and are quick to replace all of their incandescent and fluorescent lights with LEDs in their houses.

There is one potential problem, however. LEDs use individual light sources that blink on and off at high frequency rates.

Brain cells use the frequency of light as a way to translate time and if they’re exposed to rapid on-off rates, they become confused. Imagine that your brain cells have been told to expect a green light means go and a red light means stop.

If they are exposed to both at the same time, they don’t know when to stop and when to go.

The effect is less visible to the human eye than the strobe effect, which Flicker-free bulbs are on the market. That’s why some people don’t even realize it until it affects their sleep or health.

Blue Light in an LED Light

When you’re buying an LED light source, you need to pay attention to the associated BLUE light spectrum. This magic little ray is most often found in BLUE or BLUE Green spectrum light.

The BLUE light is most often produced in a fluorescing diode (LED). This is unlike BLUE light produced by other artificial light sources such as halogen, fluorescent or incandescent light.

The BLUE light radiation is the most intense and can penetrate tissue and some natural materials.

Our brains need to be stimulated by light, the natural way of getting that is from the sun. But when it comes to illuminating an aquarium, you don’t want to stimulate your fish with it.

For this reason, LED lights are ideal for aquarium lighting in that they emit less energy than halogen and incandescent lights.


This is a good question. The fact is that no one really knows, yet.

Some claim that blue lights can disrupt phytochrome photosynthesis, which could have a negative impact on plant growth. This remains a controversial topic.

I personally believe that there is no strong evidence for this any more because LED technology has changed so much.

A few years ago, the LED lights used for a planted tank were very blue. Today, as technology has advanced, LED lights are much less blue and closer to the spectrum of the sun.

There are now also lots of LED lights used for planted tanks that have warm white instead of blue.

Color Spectrum

How does the ideal spectrum affect plant cultivation?

We are used to what we know and for decades, the standard light source for growing plants and vegetables was the incandescent light bulb. These lights work by running electrical current through a tungsten filament to produce heat. This creates light, but a lot of heat as well.

The first generation of LED lights were based on this principle of incandescent lights. By the early 2000s, there were moves made in the LED world to create lights without the heat add on. This led to two breakthroughs:

{1}. Light Emitting Diode The first was replacing the tungsten filament with a diode. Diodes are semiconductors that allow electricity to pass in one direction only. The diode-based LEDs shone without any heat.
{2}. Gallium Nitride

The second breakthrough was exciting because it achieved much brighter light in a much cooler package.

The ordinary LED lights worked by restricting the light to a narrow band. Gallium Nitride diodes had unique quantum properties that made them shine much more broadly and efficiently.

The first generation of lights were only suitable for the warm white spectrum. They could not produce the more desirable cooler white light.

The next generation of LED lights were able to produce 100 lumens on the warm white spectrum or 40 lumens at 4000 kelvins on the cooler spectrum.

Color Temperature

Color temperature is a term used to refer to how pure the color is and how blue or yellow the light is. It has a direct impact on how good your plants’ growth is.

The key to success is to find the color temperature that gives you the best quality of light, which is the one that makes your plants grow healthiest.

HPS (high-pressure sodium) bulbs produce a red and orange color of light which makes the plants absorb the yellow and green colors in this light. They are becoming increasingly rare these days as LED light has overtaken them, as it is much more powerful.

Now you choose LED lights in 2K only, Pure white, 2K (cool white) or daylight (6K). The closer the temperature is to 2K, the richer and purer terms are more. But plants prefer a more blue light, so it does not give the best results for growth.

LED lights are the best quality. The plants absorb the red and blue rays because they are the most important for healthy growth. LED lights produce only these two wavelengths, which means that all the waves are of a very high quality.

So, even if the lighting is blue, it still allows your plants to absorb the benefits of the red light.

What are the Risks of Blue Light?

Researchers have discovered in recent years that blue light, found in LED and on LCD screens, has a direct and indirect effect on the circadian rhythm and sleep. Blue light tells your body that it’s daytime. So when you use blue light devices at night, it throws off your body’s natural rhythm leading to poor sleep quality.

A study show that the wavelength of the blue light produced by computer screens is at the peak of the spectrum that tells the brain to stay awake. That’s why, unlike other lights in the house, you can’t look at your phone when you go to sleep and expect to fall asleep soon. The blue light from the phone affects the sleeping cycle and causes you to have poor sleep quality.

The blue light can also create eye stress. Prolonged exposure to blue light from your phone causes eye fatigue.

Being exposed to blue light for too long can also weaken the eye’s natural filter that protects against short wavelength light, such as Ultraviolet, blue, violet light.

This weakening of the filter can eventually increase the risk for age related macular degeneration (AMD), a major cause of blindness.