It is truly the little things that can bring people together, like a common interest or a similarity. One of the most popular things to bond over is hair color.
You may wonder whether you belong to a large group of people boasting the most common hair color in the world or a small group of people possessing the rarest hair color. Likewise, if you are interested in studying hair and hair color as a career path, you may need to know what the most common color of hair you will work with is and how hair color is determined and affected over time.
In this article, you will learn everything you need to know about hair color, including the most common hair color, the rarest hair color, the prevalence of other hair colors, the factors affecting hair color, and even the most common dyed hair colors.
What Is the Most Common Hair Color?
If you live in North America or Europe, you may notice many people have a brunette hair color. This may lead you to believe that brunette is the most common hair color. But surprisingly, black is the most dominant hair color around the globe.
What Is the Rarest Hair Color?
Blonde hair and red hair are incredibly rare natural hair colors, yet red hair is the rarest hair color in the world. That said, all hair colors have various shades underneath their color umbrella. Therefore, it may be more accurate to say that strawberry blondes are the rarest color, being an incredibly light shade of red.
How Common Is Each Hair Color?
There are five main types of natural hair color:
- Black hair or very dark brown hair
- Brunette hair
- Blonde hair
- Red hair
- Gray or white hair
If you have ever wondered how many people in the world have particular hair colors, and where those hair colors originate, read more below.
Black hair comes in shades from a deep or dark brunette to jet black. In North America and Western Europe, black hair may be one of the least common, natural hair colors. However, if you travel to Latin America, Africa, Asia, Eastern Europe, and Southern Europe, you will notice that the majority of people have black or very dark brown hair. Since the combined populations of these areas are quite large, black hair makes up the majority of natural hair colors in the world. In fact, it ranges between 75% and 85% of the world’s population.
Surprisingly, natural brunettes only make up 11% of the world’s population. The majority of people consider dark brunette hair to be black hair, as it does not reflect light in the same way as most brown hair. Accordingly, their initial appearance is similar to raven-haired people. Yet, upon closer inspection, the muted brown is more noticeable. On the other hand, the brunette range more readily reflects light even on first impressions; from light brown to dark chocolate brown. These hair shades are found all over the world, although the highest concentrations are found in Europe and areas with European descendants.
Blonde hair is one of the rarest natural hair colors, estimated to comprise 3% of the world’s population. As it is one of the most sought-after dyed hair colors, this may be quite a shocking statistic to those who see blondes everywhere. It is most predominant in Northern Europe, such as Norway, Sweden, Finland, Iceland, and Denmark. Yet, it also occurs naturally in some parts of Africa, Asia, and the Pacific Islands. For instance, there are blonde-haired Solomon Islanders in the Pacific.
Red hair is very rare, only making up 2% of the world’s population. Redheads come in a broad spectrum of shades, from strawberry blonde to dark auburn. This hair color is predominantly found in Scandinavia, the United Kingdom, Scotland, and Ireland. Yet, like other hair colors today, redheads can be found all over the world in descendants from these areas.
Gray or White Hair
Although you may believe that gray or white hair only occurs when you are aging, there are also other reasons why people have gray or white hair. For instance, people may have piebaldism, which is a disorder that creates a white hair section at the front of their hairline. They may also have albinism, or a lack of pigmentation in their eyes, hair, and skin. No matter how they develop white or gray hair, they only make up less than 5% of the world’s population. Likewise, it occurs equally across geographic regions.
How Is Hair Color Determined?
You may be curious to understand how someone develops a particular hair color and what factors may affect or change that color. Read more below to find out about the fascinating science behind hair color.
What Creates Hair Color?
Ultimately, the main aspect determining hair color is the amount of pigment or melanin. There are two different types of melanin: eumelanin and pheomelanin. The type and the amount of melanin both play a role in the final hair color.
Eumelanin is a dark pigment. Naturally, this occurs in heavier concentrations in brown hair and black hair. Conversely, those with light hair, such as blondes, have very low amounts of eumelanin. Uniquely, pheomelanin is a light pigment, found in red hair. Yet, since many redheads and brunettes appear to have reddish-brown hair, they most likely have a mix of both melanin and pheomelanin.
Melanins only produce hair colors such as black, brown, yellow, or red. Moreover, different mixtures and concentrations produce various shades under these color umbrellas. As this is the case, you may wonder how white hair appears. Whereas gray hair has only a small amount of melanin, white hair has no pigment at all. The “color” white you can see is merely the light reflecting off the surface of the hair.
Do Genetics Determine Hair Color?
Now that you have sufficient knowledge of how melanin creates hair color, you may wish to know what determines melanin. While there may be other factors, genetics plays the predominant role in the creation of hair color. Yet, hair color isn’t only created through one gene, rather multiple genes may contribute to the final result. Additionally, some of these genes even establish the color of eyes, skin, spots, and freckles!
Scientists know the most about one gene, the MC1R. MC1R creates a certain receptor located on the surface of specific cells, determining melanin. Accordingly, this receptor determines if the cells produce eumelanin or pheomelanin. If this receptor is active, it triggers certain cells to create eumelanin. However, if the receptor is inactive, then cells create pheomelanin. Furthermore, there are other genes regulating the specific concentrations released by the cells.
The majority of people receive two active copies of the MC1R, one from each parent; this is what will determine a black or brown hair color. Yet, changes or variations in other genes can cause cells to produce less eumelanin leading to blonde hair. For example, researchers discovered a mutant gene, the KIT ligand gene, plays a dominant role in creating blonde hair colors in Northern Europe.
In rare circumstances, one of the copies of MC1R is not active. This variation causes the cells to produce a lower amount of eumelanin and a higher amount of pheomelanin. When this occurs, hair colors are blonde, strawberry blonde, or reddish-brown. Yet, in some people, both copies of the MC1R gene are inactive. As such, cells only produce pheomelanin leading to bright red hair. This explains why red hair only occurs in such a small portion of the population; both parents must carry a copy of an inactive MC1R.
Does Region Influence Hair Color?
One of the strongest theories for why hair colors may be lighter or darker involves geographic region and evolution. People who live in areas where there is a great deal of sun often have dark skin, dark hair, and dark eyes, with a few exceptions. On the other hand, people who live in colder and darker regions tend to have pale skin, light hair, and light eyes. Whereas darker features inhibit the absorption of sunlight and vitamin D, lighter features allow for greater absorption. It could be the case that genetic mutations occurred allowing for lighter features over migrations, or people originated and adapted to the climate in these areas.
There are a few exceptions to this theory. For example, blonde hair is found all over North America or black hair is discovered all over Europe. Researchers can explain most of the exceptions through dependents and migrations. For instance, Scandinavian Vikings made their way to different territories spreading their characteristic blonde, red, or brown hair.
That said, scientists cannot attribute some hair colors to ancestors traveling. For example, the blonde hair found with the Melanesians in the Pacific Islands is a unique case. It turns out European ancestors did not disrupt the natural black hair lineage. Rather, a gene mutation arose by itself on the Solomon Islands and nearby islands. Specifically, the gene TYRP1 goes through an amino acid change. Remarkably, this gene mutation does not occur in light-haired Europeans.
Does Age Affect Hair Color?
You may notice that some people’s hair color changes over time. For instance, the most common change is hair transforming into gray or white when people age. As you may recall, melanin determines hair color. Over time, hair follicles create less melanin, causing a lack of pigmentation in hair. Scientists believe that a gene, specifically the IRF4 gene, may play a role in this age-related loss of pigmentation.
However, remarkably, this can also occur in the opposite direction! For example, white-haired children or very light blonde children often develop darker hair as they become teenagers.
Can Hormones Change Hair Color?
One of the reasons hair color can change over time is due to dramatic hormone changes. This may be part of the reason hair color can change when children become teenagers, when women are pregnant or post-partum, when women go through menopause, or people experience disorders, diseases, or treatments disrupting hormones. Hormone changes can often lead to a decrease or increase in melanin production.
How Does Stress Affect Hair Color?
Similar to aging, stress can cause hair to prematurely turn gray or white. Stress activates the body’s fight-or-flight responses, which are sent throughout the entire body. Chronic stress can have a serious impact on all parts of the body including hair follicles. Namely, it causes the body to release a specific chemical into hair follicles, norepinephrine. This chemical alters the stem cells which were going to become pigment cells. Whereas the cells would typically take time to develop into pigment, they rapidly develop into pigment cells instead. In an orderly fashion, they move out into the hair. Unfortunately, since this happens at a fast-forward pace, there are no new cells waiting to become pigment.
Does Health Play a Role in Hair Color?
Although you may know health plays a role in the strength, softness, shininess, and length of your hair, you may not know that it can also have an effect on your color. In fact, premature gray or white hair has been linked to nutritional deficiencies. Particularly, there is evidence to suggest vitamin B12, vitamin D, copper, iron, and zinc deficiencies, and protein deficiencies can all cause changes to hair pigmentation. Furthermore, certain medications, alcohol, and smoking can alter hair color.
Of course, other environmental factors that affect health may play a role in hair color changes as well. Whereas genetics may account for 30% of premature loss of pigmentation, the other 70% may be due to environmental exposures. Climate change, UV exposure, and contamination of water, air, and food can all contribute to altered cell behavior.
What Are the Most Common Dyed Hair Colors?
Whereas natural hair color is certainly interesting, dyed hair colors are equally as intriguing! The most appealing elements of dyed hair are that you can choose whichever hair color you like the most and you do not have to limit yourself to natural colors. You can choose from a wide range of colors, shades, and tones.
Even though that is the case, the most common dyed hair color in the world is blonde hair. Its popularity dates back to the 1950s when Marilyn Monroe became known for her platinum blonde look. Today, you can choose from light ash blonde to dark blonde.
Of course, the most popular color choices at any given time may depend on a multitude of factors. Although blonde has taken the lead overall, it may differ based on geographic location, culture, and periodic trends. Moreover, social psychology may be a significant factor in hair color choice. Correspondingly, women may be more attracted to dyeing their hair than men. In the United States, more than 75% of women dye their hair at least once. This may be because hair dye is mainly marketed toward women, women are held to high beauty standards, and there is a stigma around aging and graying hair for women.
How Does Hair Dye Change Hair Color?
Although many people may have dyed their hair, they may not know the process their hair goes through in order to change color. Now that you understand how your body creates your natural hair color, you may wish to know how hair dye changes that color.
First, hair dye must break down the protective layer that surrounds the hair shaft, the hair cuticle. The majority of hair dyes include a high alkaline chemical, typically ammonia, to lift the hair cuticle up and away from the shaft. In this way, the dye can reach the underlying pigment within the hair shaft.
Second, if you have darker hair and want a lighter color, you must lift your hair pigment to a significant degree. Otherwise, the dye will have no effect upon the hair color. Since this is the case, companies add hydrogen peroxide to most hair dyes to react with the melanin in a hair shaft. This chemical removes the natural pigmentation.
After removing natural pigmentation, a colored, permanent pigment can bind to the hair cortex, or the majority of the inner hair shaft. The hair color will not wash, only fading a small amount, as the dye molecules enter and expand within the shaft. On the other hand, if opting for a semi-permanent hair dye, the dye mainly stays on the surface of the shaft which is why it washes out easily. In this case, the molecules do not expand within the shaft. Likewise, with some hair dyes whether they are permanent or semi-permanent, they may fade. This most commonly occurs with red hair dye, as the red pigment may not fully penetrate the cortex or expand.
Moving Forward with Common and Popular Hair Colors
Whether you belong to the most common hair color in the world or fall into the rarest types of hair color, you will surely feel a sense of belonging knowing others possess the same colored hair. You may even wish to dye your hair another natural shade or a rainbow of primary hues.
If you are planning on changing your hair color and are searching for the answer to which the most popular hair color is, then the answer most probably is, “The one that you don’t have!”
If you are a hairstylist, advancing in your hair color career is certainly easier when you know the science behind hair color. In this way, you know exactly how natural hair color occurs, what factors affect that color, and how to achieve different hair colors for your clients. You may even be a trusted consultant for certain clients, as you will know exactly why their hair may be changing colors.
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