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Color Blindness: What Is It, What Are The Causes & Symptoms?

Hugo and Maya are smiling behind a white line. In it there are different coloured circles touching each other.

Imagine a world where the sky is not blue, leaves are not green, and traffic lights are not red. For people with color blindness, this is a reality. In this article, we will explore the causes and symptoms of color blindness and discuss how individuals can manage the condition to ensure that they have equal access to the world around them.

What Is Color Blindness?

Color blindness is a condition in which a person has difficulty distinguishing between certain colors, or cannot see colors at all. Particularly greens and reds, and occasionally blues. The color blindness medical term is Color Visual Deficiences (CVD).

This condition, also known as color vision deficiency, is caused by abnormalities in the cone cells located in the retina of the eye. The cone cells are responsible for detecting light and color, and when they are not working correctly, it can result in color blindness.

What Are The Types Of Color Blindness?

Now that you know what color blindness is, let’s learn more about its types. There are several kinds of color blindness, and the way they affect the way you see colors is different in each of them. Check out which are some color blind types:

Red-Green Color Blindness

Red-green color blindness, also known as deuteranopia color blindness, is the condition’s most common form. It affects about 8% of men and 0.5% of women of Northern European descent. 

It is characterized by the inability to distinguish between red and green colors or to see them in their true brightness. This type of color blindness occurs when the medium and long-wavelength sensitive cone cells (M and L cones) in the retina do not work properly.

Blue-Yellow Color Blindness

Blue-yellow color blindness is less common than the red-green color kind. It occurs when the short-wavelength sensitive cone cells (S cones) in the retina are not working correctly. People with blue-yellow color blindness have difficulty distinguishing between blue and yellow colors, as well as between blue-green and red-green colors.

Complete Color Blindness

Complete color blindness, also known as achromatopsia, is the rarest form of color blindness. It affects only about 1 in 30,000 people. It is characterized by the inability to see any colors at all and can also cause problems with visual acuity and sensitivity to light.

What Are The Symptoms Of Color Blindness?     

Color blindness symptoms can vary in intensity from mild to severe. Some individuals with mild symptoms may not realize they have a color deficiency. Parents may notice color vision problems in children during early learning stages. Color-blind children may face difficulties in school, particularly in subjects that require color recognition, such as art and science. Here are some most common symptoms of color blindness:

Difficulty seeing colors

One of the prevalent indications of color blindness is the trouble in perceiving colors and their intensity in the regular manner. People with color blindness may see colors differently or not at all. For example, websites that rely heavily on color to convey information may be challenging for individuals with color blindness to interpret, leading to confusion and misunderstandings. Because of this, web accessibility is important to color blind people.

Not differentiating shades of the same or similar colors

A frequent sign of color blindness is the incapacity to distinguish between hues of comparable or alike colors, typically occurring with red and green or blue and yellow. For example, someone with red-green color blindness may have difficulty distinguishing between a red apple and a green one.

Others vision problems

Color blindness, in most cases, does not impact the sharpness of vision unless it’s a severe form known as achromatopsia. People with color blindness can still perceive fine details and read small print. Achromatopsia is a rare condition where individuals are unable to see any color and can only see everything in shades of gray. This condition is usually accompanied by other vision problems such as amblyopia, nystagmus, light sensitivity, and poor vision in bright light.

What Causes Color Blindness? 

What causes color blindness may vary for each person, but the most common color blindness is usually caused by a genetic mutation.

Genetics Causes Of Color Blindness

Color blindness is caused by a genetic mutation that affects the cones, which are the cells in the retina that are responsible for color vision. There are three types of cones, each of which responds to a different range of colors. People with normal color vision have all three types of cones working properly, while people with color blindness may be missing one or more types of cones, or may have cones that do not work properly.

Non-genetic Causes Of Blindness

While color blindness is usually an inherited condition, it can also be caused by certain diseases, medications, or exposure to toxins. Some of the non-genetic causes of color blindness include age-related macular degeneration, glaucoma and diabetes.

Some medications, such as chloroquine and hydroxychloroquine, can cause color vision problems too.

In addition, head injuries or trauma to the eye can damage the retina, such as exposure to certain chemicals, like carbon monoxide.

Am I At Risk For Color Blindness?

If you are wondering whether you are at risk for color blindness, it is important to understand the different factors that can contribute to this condition. Men, in particular, are at a higher risk for being born with color blindness than women. This is because the genes responsible for color vision are located on the X chromosome, of which women have two copies, while men only have one.

How Can I Find Out If I Have Color Blindness?

If you are experiencing symptoms of color blindness or have a family history of the condition, it is important to consider testing for color blindness.

Color Blind Test 

One of the most common methods for testing for color blindness is the Ishihara color vision test. This test involves looking at a series of images containing colored dots and trying to identify numbers or patterns within them. People with normal color vision can easily identify the numbers or patterns, while those with color blindness may have difficulty seeing them.

Another test commonly used to diagnose color blindness is the Farnsworth-Munsell 100 Hue Test. This test involves arranging colored caps or tiles in order of hue. Those with normal color vision will probably be able to arrange them in the correct order.

Genetic Testing 

You may also consider genetic testing. This involves analyzing your DNA to determine if you carry genetic mutations that can cause color blindness. While genetic testing cannot diagnose color blindness, it can help identify if you are at risk of passing the condition on to your children.

How Many People Are Color Blind? 

Color blindness is a condition that affects approximately 8% of men and 1 in 200 women. Globally, it is estimated that there are around 300 million people with color blindness, which is nearly the equivalent of the entire population of the United States!

What is The Treatment For Color Blindness? 

Although there is no known cure for color blindness, there are treatments available that can help alleviate the symptoms associated with this condition. It is important to note that not all individuals with color blindness require treatment. For some people, the symptoms may be mild and not interfere with their daily lives at all. 

Glasses And Contacts 

One common treatment for color blindness is the use of color blind glasses or contact lenses that have especially designed filters. These filters can enhance the color contrast between different colors and help individuals better differentiate between colors. These glasses or contact lenses work by selectively filtering out certain wavelengths of light that cause confusion for those with color blindness.

Visual Aids 

Another option for those with color blindness is the use of visual aids such as color-coded charts, digital devices, or computer programs that help individuals interpret color better. These visual aids can be used in a variety of settings, from the classroom to the workplace, to help individuals with color blindness perform tasks more effectively. Also, making your content accessible to color blind people is an important step towards creating an inclusive environment.

How Much Do Color Blind Glasses Cost? 

The cost of color blind glasses can vary depending on the brand, style, and where you purchase them from. Some color blind glasses can cost anywhere from a few hundred dollars to over a thousand dollars. However, there are also more affordable options available on the market, with some pairs at between $200 and $400.

What Are The Color Blind Person Rights?

Color blindness affects millions of people worldwide. Despite this, color blind individuals often face barriers and discrimination in various aspects of their lives. As a result, there are various laws and regulations in place to protect the rights of color blind people and ensure they have equal access to opportunities and resources as anyone else.


Denying job opportunities to color blind individuals solely based on their condition is considered discriminatory. Employers are required to make reasonable accommodations to allow color blind individuals to perform their jobs safely and effectively. 

For example, a color blind person may be able to use technology or specialized equipment for accessibility to help distinguish colors or work in roles where color distinction is not essential.


In many countries, color blindness is not an automatic disqualification for a driver’s license. However, color blind individuals may need to pass alternative tests or demonstrate different methods of identifying traffic signals and road signs.

Piloting Aircraft 

In the United States, color blind individuals are allowed to obtain a private pilot’s license, but there are restrictions on the type of aircraft they can operate. Commercial pilots, on the other hand, are required to have normal color vision. However, the Federal Aviation Administration (FAA) allows color blind people to use certain color vision aids to meet the color vision requirements for obtaining a commercial pilot’s license.

Frequently Asked Questions 

When it comes to color blindness, there are a few questions that come up frequently. In this topic, we’ll answer some of those to help provide clarity on the subject. Check it out!

Are Dogs Color Blind?

Dogs are not completely color blind, but they do have a limited ability to see colors. Specifically, dogs have two types of color-sensitive cells (called cones) in their eyes, while humans have three. This means that dogs can see some colors, but their ability to distinguish between colors is much more limited than that of humans.

Are Cats Color Blind? 

Similar to dogs, cats are not completely color blind, but their ability to see colors is limited. Cats have two types of cones in their eyes as well, which means they can see some colors, but their color vision is not as rich as humans.

Can Women Be Color Blind? 

Women can be color blind, but it is a much less common condition than it is for men. Color blindness is a genetic condition that is passed down from parents to their children. The genes responsible for color vision are found on the X chromosome. Since women have two X chromosomes and men have one X and one Y chromosome, women are less likely to inherit two copies of the gene responsible for color blindness.


While it is typically not a severe condition, color blindness can impact a person’s daily life in significant ways. Knowing the causes and symptoms of color blindness can help individuals understand why they may be experiencing difficulties with color perception. By being aware of the condition, people can take steps to manage their symptoms and ensure that they have access to the same opportunities as everyone else.

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