The Science of Graying Hair

While we talk often about wrinkles and dry skin, nail and hair problems are also an important part of dermatology. We’re here to talk about a concern that a lot of people have, but don’t often like to talk or even think about: The dreaded graying hair.

How do we get color?

Like skin color, melanin is responsible for the color of human hair. There are two types of melanin involved; eumelanin is responsible for producing dark hair, and pheomelanin is responsible for lighter colored hair, which accounts for the difference in hair color in humans. Gray/white hair, on the other hand is not a "color" but simply lack of color, or melanin. With age, most people slow their production of this pigment in the hair follicles, causing white hair to grow. The speed and timing at which this grows varies widely (some start as early as their teens while some may not have any white hair in their 60s). Generally, Caucasians start to gray earliest, followed by Asians, and then Africans.1 Due to white hair strands being more noticeable against darker hair, the change in appearance may be less noticeable for people with lighter hair color.

“There is only one cure for gray hair. It was invented by a Frenchman. It is called the guillotine.” P. G. Wodehouse

Graying seems to be a near universal phenomenon, and something that has bothered people from ancient times, and across various cultures. Graying hair, like other cosmetic changes in the skin due to aging, has significant psychological impact, and is inextricably tied to social norms and expectations. For this reason, graying hair is perceived differently between men and women, and the dynamic also varies across different cultures. It can also affect job prospects as well as relationships.2 Graying hair will eventually happen to almost everyone.

Gray Hair Myths

Genetics, not stress: Blaming premature graying on stress has been popular3, and there is some evidence that hair health can be correlated to increased cortisol (stress hormones)4. There are also some rare medical conditions that affect hair color, but genetics appears to be primarily responsible for when and how fast your hair will gray. You will likely follow the pattern that your parents went through with regard to how fast your hair will turn gray.

50/50/50 rule: The rule states that at age 50, 50% of the population has 50% gray hair. While this is not a bad generalization as far as anecdotes go, it seems that 50% graying isn’t quite this common5 but most people, by the age of 50, most people will have some gray hair.

Pluck a gray hair; two more show up for the funeral: This is similar to the myth of shaving hair, causing it to grow back faster, darker, or coarser6. With gray hair, the number of hair that has lost its color can increase quickly, over the period of a few years, giving the perception that something like plucking may have caused this to occur. In reality, increased gray hair is most noticeable during the early stages of graying (when people tend to pluck - it’s too impractical to pluck out a lot of hair). That said, it’s still a very bad idea to get into the habit of plucking your hair.

Treatment Dos and Don'ts

While we are beginning to unravel the genes involved in loss of hair color, it will likely be decades before there will be a “cure” for graying hair. In the meantime, concealing and coloring is by far the most convenient and popular “treatment” choice. Coloring your hair at the stylist/salon or using a store bought hair coloring product is relatively low maintenance. The drawback is that hair grows relatively quickly, and roots of the hair, which are white, can become noticeable in a week or two, so in between visits, you will likely need to use a hair coloring product to maintain your look.

Highlights: Highlighting your hair can be a great way to conceal graying strands as well as giving your hair a new spark! There are a million different variations to fusing different colors, and it can add a new sparkle to your looks while concealing any signs of gray.

Braids/Knots/Headbands/Curls: Another creative solution similar to highlights that involves a change in hairstyle. Gray hairs can be a shocking change, but very often it’s about perspective. A major change in hairstyle can not only be effective in hiding gray hair, but it can also give you a brighter, more positive outlook about your hair.

Don't Do List

Plucking: Plucking your hair can be tempting, especially if you only have a few isolated strands of white hair. Don’t fall for this temptation, as plucking damages your hair follicles. It likely won’t destroy them immediately, but hair grows relatively quickly, and if plucking becomes a habit, you may end up having no hair instead. Once graying starts, plucking will quickly become unmanageable as a strategy anyways, and in the meantime you definitely don’t want to be damaging your hair follicles.

Dark Dyes: If you naturally have dark hair, too bad! If you’re more of a blonde or light brown, use a lighter toned dye to cover your white hairs. White hairs are more noticeable in contrast to darker hair, which is why it often seems like Asians have more gray hair, even though they tend to get gray hair later than Caucasians. Using darker shades can hide the gray nicely, but it can accentuate the white hairs that show up from the roots.

3Not that something as ubiquitous and general as stress is all that easy to avoid.
5The rate of people with 50% gray hair at age 50 is 6-23%. This said, 74% of people aged 45-65 had some amount of gray hair.
6Despite constant reminders that this is untrue, this myth just will not die. At most, it gives the shaved hair a “blunt tip” making it possibly more noticeable.