When growing facial hair of any kind, it is not unusual for men to discover red hairs in their beards, sideburns, and even their mustaches, even when they do not have red hair on their head or body.
But what is the cause of this common phenomenon, and what secrets does it hold about our shared ancestry?
What Causes Red Beards?
It is indeed a strange phenomenon, particularly when no one else in your family has red hair, however there is a relatively simple scientific explanation as to why this occurs.
The answer is genetics.
While most people might assume that we have a specific gene that gives us brown hair etc, it is actually a little more complex than that.
The gene that determines the color of our hair is called an ‘incomplete dominant hereditary trait’, and with incomplete dominance, there is not a single gene that governs our hair color – more like a combination of unfinished genes that influence one another and blend together.
This is why when a man shaves one month, his mustache might be lighter, or even blonde, and why other times he can shave and it grows back with a red tint – all despite having a head of dark brown hair.
So, What Decides The Color?
Due to the seemingly random blend of incomplete genes, there is really no way to predict what hair and beard color a person is going to have with 100% accuracy.
The combination of genes that you possess is based not just on your parents, but also their parents, and their parents’ parents, which means there is a lot of room for variation, anomalies, and a surprising sprout of red hair in your beard.
Within northern and western Europe, red hair is a genetic mutation that is incredibly prominent, particularly focused amongst people of Celtic heritage found in the British Isles.
People who have red hair all over their bodies have two of these supposedly mutated genes (known as the MC1R gene), while people who have just the one mutated gene can grow red hair in unexpected places, like their beard, sideburns, mustache, and even eyebrows.
However, while the red hair gene might be especially prominent amongst Celtic people, the presence of red hair in your beard is not necessarily an indication of Celtic heritage – instead just representing a gene that is one of millions present within the genetic makeup of your ancestors, grandparents, and parents.
Why Do Genes Do This?
To understand how the genes behave, we first need to understand what genes create which hair colors.
The pigmentation genes that people have can vary.
Those who have very dark brown or black hair have a gene called eumelanin that produces black pigments, while redheads have a gene called pheomelanin, which produces red pigments.
People with blonde hair have a much more limited amount of both pigments, which is why their hair is fairer and pale in color.
Now that we understand which genes create which pigments, we can now talk about the way they can be combined, as a result of our family history, and the genes present in our overall genetic coding.
One major role of the MC1R gene is to recode for a protein called melanocortin.
The job of melanocortin is to convert red pigments into black ones, but if the individual in question has two mutated MC1R genes, then the protein won’t be able to be as effective, leading to the person having red hair instead of darker colored hair.
Likewise, those with brown hair and a red beard can thank the way the genes behave. Scientists have found that those with this combination are simply a reflection of their MC1R gene reacting differently within different parts of the body.
This differential expression of pigment can result in a darker brown eumelanin in their hair, and a yellowish-red pheomelanin in their beard hair.
What Else Does Pigment Determine?
Of course, with certain pigment genes, there are various genetic traits that accompany them.
For Full Redheads
For redheads with two MC1R genes, these traits are much more defined, and can consist of a propensity to get sunburn, insufficient response to local anesthetics, pale skin tone, sensitivity to thermal pain, and a higher risk of melanoma.
For MC1R Carriers
For those who merely carry one MC1R gene, these traits are still present, albeit in much lower levels, and many who can grow a red beard will experience none of the associated health risks that full redheads are subject to.
When Can This Happen?
Men can develop this combination of hair colors at any stage throughout their lives, but it tends to be quite prominent as they age.
This is because the pigment-producing cells of the beard and hair age at different rates, resulting in different colored hair and beards.
It would perhaps be easier to think of the different genes fading or reducing at different rates – with the red pheomelanin sticking around the longest in the facial hair.
So, What Does This Mean For The Individual?
While it doesn’t denote any specific Celtic heritage in the person’s family history, what it does mean is that those with brown hair and red beards are carriers of the redhead gene.
This means that, as they too have children and grandchildren, they have a chance of continuing this trend throughout their own lineage.
And there we have it, everything you need to know about why men grow red hair on their beards.
This common phenomenon is laden with misconceptions and urban myths, and while these can make interesting stories and sources of humor amongst our friends, the real reason lies a little closer to home – hidden in the countless ancestral genes that blend together to make up our very being.