Living with a visual
color deficiency.

The world is rich in a variety of hues, from red and blue to green and yellow. But for a small segment of the population, differentiating between these colors can be a challenge.

Although the common term for this condition is color blindness, a more apt explanation is to say that some people experience color deficiency. According to the American Optometric Association, 8% of the world’s population has this visual condition.

Dr. Bret Bodenhamer with Bodenhamer Eye Consultants explains that true color blindness is a rare condition where an individual only sees in tones of gray. A deficiency is when people have trouble differentiating between shades of the same color or are unable to discern one color from another, such as red from green.

“In the eye care world, we see a lot more people who are color deficient rather than being totally colorblind,” Dr. Bodenhamer says.

Color deficiency occurs when there’s a problem with the photoreceptors located inside a person’s retina. The retina consists of rods, which help with seeing at night, and cones, which help with seeing bright lights and perceiving colors.

According to the American Optometric Association, 8% of the
world’s population has this visual condition.

There are three types of cone cells: red, blue, and green. If a person is missing a cone cell or is deficient in one, that is when the individual will experience color vision deficiency.

“The most common deficiency is red and green, followed by blue and yellow,” Dr. Bodenhamer says.

The majority of people who experience a color deficiency have this issue due to a genetic condition. Although it’s inherited through the mother’s genes, color deficiency affects more men than women. According to the National Eye Institute, roughly one in 12 men have some form of the condition. For those born with color deficiency, many people don’t realize they have the condition until they’re grown adults.

In addition to those born with color deficiency, others can become color deficient over the course of their lifetime due to a number of factors, like particular health conditions or as a side effect of taking certain medications. When a person develops color deficiency, it can often alter their daily life. 

This is the case for Walter Johannpeter, who lives with a color deficiency. Although he has learned to adapt his life around having the condition, he wasn’t even aware of the problem until he had to perform a task at work. During a summer job working on the assembly line for Ford, part of Walter’s duties was installing wires that helped power a car’s ignition. When he failed to do this task correctly, he discovered there was a problem with his color vision.

According to the National Eye Institute, roughly one in
12 men have some form of the condition.

“I couldn’t tell the difference in the colors of the wires they were telling me were there,” Walter says.

The auto company gave Walter a color blindness test, which confirmed he had an issue differentiating between hues, particularly reds. Although Walter, who is now retired, went on to become a civil engineer, his condition still impacts his daily life in numerous ways.

“A lot of the dashboard warnings on your car are in red, and a lot of the emergency notices that appear on TV are in red with a dark background, so it’s hard for me to read them,” Walter explains.

Having trouble seeing the color red also impacts how Walter sees food packaging. As a diabetic, it’s important for him to monitor his daily carbohydrate intake, and numerous boxed and canned goods have red text with a dark background, making it harder for him to see the nutrition facts or ingredient list. One way Walter has learned to adapt to his condition is through shining a bright flashlight on the packaging or other physical objects, which makes it easier for him to distinguish colors and read text. When it comes to using a screen, Walter keeps his cellphone on the dark mode setting to help him discern words on the screen.

Dr. Bodenhamer points out that color-correcting lenses can help with color deficiencies. When these specific lenses are worn, they can fill in the color a person is deficient in and allow them to see a full color spectrum. Since color deficiency can be genetic or acquired later in life, Dr. Bodenhamer recommends patients get their vision checked regularly by an eye care professional.


The Ishihara Test

The Ishihara Test is a widely recognized and utilized tool for diagnosing color vision deficiencies. Developed by Dr. Shinobu Ishihara in 1917, this test consists of a series of plates, each featuring a circle filled with various colored dots that form numbers or shapes discernible to those with normal color vision. Individuals with color vision deficiencies may struggle to identify the figures correctly or at all. This simple yet effective test remains a cornerstone in the field of optometry, helping to accurately identify color vision deficiencies.