closeup of human blue eye

15 Mindblowing Facts About Eyes

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How many colors can our eyes see? What are the perks of having two eyes instead of just one? And just how fast are the eye muscles?

In today’s post, we’re bringing you some of the most interesting eye facts known to science. From eye colors and color vision to the eye’s unique characteristics, there’s a lot to tickle your curiosity.

Explore now the most remarkable facts about the human eye.

Fact #1: The Older You Get, The Less You Cry

Is it because life makes you tougher? Well, you can say that. But mostly it’s because the lacrimal glands located in the outer corner of each eye produce fewer tears as we age.

Fact #2: Your Eye Muscles Are the Fastest in Your Body

When you blink or move your eyes it’s the six muscles in each eye that do the work. Eye muscles can contract in less than 1/100 of a second.

Fact #3: All Our Ancestors Had Brown Eyes Up Until About 10,000 Years Ago

Brown eyes have a higher concentration of the pigment melanin than lighter-colored eyes. This pigment protects the eye against UV radiation. It helped our ancestors survive hot climates. Talking about eyesight facts to remember!

Here are two more interesting brown eye facts:

Fact #4: People with Blue Eyes May Have a Common Ancestor

According to a Danish study, a mutation affecting the OCA2 gene 6,000 to 10,000 years ago created the first pair of blue eyes at a time when all people had brown eyes.

closeup of male right blue eye and eyebrow

Here are some more blue eye facts for you:

  • Blue eyes have less melanin than darker-colored eyes, which makes them more sensitive to light. If you have blue eyes, you need to protect them from the sun wearing sunglasses.
  • Babies born with blue eyes may grow up to have a different eye color as their iris produces more melanin during childhood.

Fact #5: Gray Is the Least Common Eye Color

Less than 1% of people have gray eyes. Gray eyes have the least amount of melanin of all eye colors.

But if we think of gray eyes as a very light hue of blue eyes, as some people do, then the least common eye color is green. Only around 2% of people have green eyes according to the same source.

Fact #6: Night Vision Wouldn’t Be Possible Without Your 100 Million Rod Cells

Rods are photoreceptor cells in the retina at the back of the eye. They are sensitive to dim light and make possible vision in low light—such as in the dark. A whooping number of them work together each time you feel your way to the bathroom in the middle of the night.

On the other hand, there are ”only” about 6 million cone cells. These are sensitive to bright light and pick up the colors green, blue, and red, which the brain combines to make all the other colors we perceive.

Fact #7: Rod Cells Can Detect 500 Shades of Gray

Just how good are rod cells in the retina at detecting light and darkness? Good enough to detect hundreds of shades of gray. Maybe this explains, at least in part, why we like gazing at the Moon?

grayscale moon rising out of black background

Fact #8: Having Two Eyes Makes Seeing in 3D Possible

Having two eyes instead of one comes with a big advantage—it enables depth perception.

The brain receives two different images, one from each eye. By comparing them, it can calculate distances between the object in focus in a way it couldn’t if we had only one eye. Put another way, you may look with your eyes, but you see with your brain.

Having two eyes also enables a wider field of vision. As far as deep, broad vision is concerned, two eyes are better than one.

Fact #9: Your Eyes See Images Backwards and Upside Down

When you look at something, the built-in organic lens in the eye creates an image on the retina. This image is upside down and backward until the part of the brain responsible for vision turns it around. You can think of this process as a kind of amazingly fast live footage video editing.

Fact #10: Your Eyes Can See Around 10 Million Different Colors

Now here’s one of the most impressive facts about the human eye, one that visual artists especially love.

Human eyes can see more colors than human mouths can name—around 10 million. Unless color-blindness comes in the way, that is.

Color blindness occurs when one of three types of cone cells in the retina is missing. For example, people who have no red cones cannot see the color red, a condition known as protanopia.

Fact #11: Up to 80% of Learning is Visual

Visual pathways following the eyes-brain route enable most learning. While all our senses contribute to learning, it’s the eyes that feed our brains the most information.

woman writing on whiteboard full of colored writing

Our list of fun facts about the eyes isn’t done just yet, so read on.

Fact #12: Your Eyes Process About 36,000 Bits of Information an Hour

That amount of processing comes of course at a cost. The eyes use about 65% of brainpower, more than any other organ of the body.

Fact #13: Your Eyes Can See a Candle Flame 1.6 Miles Away

Given the right atmospheric conditions, that is. While some sources claim the human eye may see a candle flame as far away as 10 miles, that’s very likely an overstatement. But 1.6 miles is still quite impressive, isn’t it?

Fact #14: Your Eyes Focus on About 50 Things Every Second

Your eyes may not seem to move as much during the day as your hands or legs, but they sure do a lot of work.

Fact #15: The Iris of the Eye Has 6 Times More Characteristics Than a Fingerprint

An iris has 256 unique characteristics compared to only 40 for a fingerprint. What’s more, the blood vessels on the retina have a unique pattern. That’s why retinal scans work as reliable security checks.

closeup of two human eyes

Your Eyes Are Amazing

After so many facts about eyes, you may feel a new appreciation for the two round wonders under your eyelashes that are now reading these words.

Eyes are remarkable organs, second in complexity only to the brain. But because they usually work so well and smoothly, it’s easy to forget about them.

You don’t have to wait for your eyes to feel tired or itchy or become red to start paying attention to them. One way to take care of your eyes is to eat foods that support healthy vision.

A full-spectrum vision health supplement like SightC can also help keep your eyes healthy—it’s rich in antioxidants and phytochemicals from goji berries and other natural sources.

In the end, your eyes deserve a bit of care, don’t they? Give them the nutrients they need, get enough rest, and avoid eye strain as much as possible to keep your eyes healthy for years to come.

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