Some children start life as platinum blonds — often called "towheads" — but experience a darkening of hair color before they reach puberty. Just what causes this change in hue?
To begin: Your hair color is determined by the amount of natural pigment, called melanin, you have in your hair. Two distinct types of melanin exist — eumelanin and pheomelanin — and the ratio of these pigments guides hair color.
Eumelanin can be further broken up into two flavors: black and brown. Essentially, the more eumelanin you have in your hair, the darker it will be.
Pheomelanin regulates the redness of your hair, similar to the way eumelanin controls the darkness of your hair. The more pheomelanin you have, the redder your hair will be, though the color may not be entirely visible if you also have a large amount of eumelanin as well.
The exact concentrations of eumelanin and pheomelanin in your hair depend on which genes are turned on or off. Importantly, the expressions of the genes responsible for hair color are not constant throughout your life — these shifts in gene expression give rise to the changes in hair color that some kids experience.
Typically, children with dark hair will keep their dark hair into adulthood. But some children with light hair, including towhead blonds, strawberry blonds, dishwater blonds and redheads, see their hair go dark brown by their 10th birthday.
The reason for this change is because the amount of eumelanin in your hair increases as you mature, according to some research. But just why eumelanin production ramps up (or why those specific gene expressions change) is not entirely clear.
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Originally published on Live Science.
FAQs
The biggest contributing factor is your hormones. Generally speaking, blonde hair usually turns brown – or at least darker – as we age. We've all seen photos of relatives or friends who were so fair as a child that their hair was almost white.
Why does my blonde turn dark? ›
Hormonal Changes: Hormonal fluctuations, especially during puberty, pregnancy, and menopause, can affect melanin production. These changes can result in blonde hair darkening over time.
Why does some people's hair get darker as they age? ›
The genes for making melanin might turn on or off over the course of a person's lifetime. If this happens in the cells at the bottom of your hairs, your hair might change color!
What is the rarest hair color? ›
Yes, auburn or red hair can be natural. Red hair is in fashion these days. Natural red hair is the rarest hair color in the world. A mere one to two percent of people are born with auburn hair.
Do blondes go grey faster? ›
Talking of natural hair colour, is it just us, or does darker hair seem to go grey faster than blonde? Both Ricardo and Eva are quick to clarify that there's no correlation between natural hair colour and our propensity to grey. The speed of greying is in our genetics, they tell us.
Why do they call blondes a toe head? ›
Typically, blond hair grows darker as people age — even if you are blond as an adult, you hair will still be a darker shade of blond than it was when you were a young child. The word comes from the noun tow in the sense of "flax," which is usually a golden color.
Does blonde hair darken with age? ›
Blonde fact #3: Natural blonde hair darkens over time
Blonde locks tend to darken over time to brown, or even black. If you're still a natural blonde – consider yourself lucky!
Why are blonde babies born with dark hair? ›
There are over 120 genes involved in the pigmentation of mammals. With this complexity two blond adults could produce a dark haired baby or one dark haired and one blond.
How to go dark after blonde? ›
How to Go From Blonde to Brown Hair
- Step 1: Don't Go Too Dark at Home. ...
- Step 2: Find a Professional You Trust. ...
- Step 3: Start With Clean Hair. ...
- Step 4: Use a Filler Shade First. ...
- Step 5: Apply Brown Dye. ...
- Step 6: Finish With a Hair Glaze.
Sometimes it is also influenced by genetic factors. Some people start to have white hair in their 30s or 40s. But others have it as early as their teens or 20s.
Hirsutism is excess hair growth on the body or face. For women, the hair may grow in areas where men often have a lot of hair, but women often don't. This includes the upper lip, chin, chest, and back. It's caused by an excess of male hormones called androgens.
Does pubic hair stop growing? ›
As you age, your pubic hair, just like the hair on your head, will naturally start to thin and turn grey. Part of the aging process includes hair loss and the slowing of the rate of hair growth. Typically, hair in the armpits, chest, and pubic region will start to thin and turn grey later than scalp hair.
Do blonde toddlers stay blonde? ›
Hair Color Changes Throughout Life
Even then, babies and toddlers with blonde or red hair often develop brown hair as they age. It may darken slowly during early childhood, or it may change more abruptly during adolescence due to hormonal changes.
Why is my white hair turning dark again? ›
However, the rate of hair colour loss is largely determined by your genes. The chances are that you will experience premature greying if your parents do. However, certain nutritional deficiencies and underlying medical conditions may play a role. In these cases, yes, white hair can turn black again.
Why is my blonde fading so fast? ›
Additionally, frequent washing, use of hot water, exposure to sunlight, use of harsh shampoos, and styling with heat tools can all contribute to color fading. Proper hair care, including using color-safe products and minimizing exposure to these factors, can help prolong hair color vibrancy.
