The primary chemical responsible for making hair darker is melanin. This pigment is produced by cells called melanocytes and is responsible for the color of our skin, hair, and eyes.
Types of Melanin
There are two main types of melanin:
- Eumelanin: This type of melanin gives hair its brown or black color.
- Pheomelanin: This type of melanin gives hair its red or blonde color.
The ratio of eumelanin to pheomelanin determines the shade of hair color. More eumelanin leads to darker hair, while more pheomelanin leads to lighter hair.
Factors Influencing Hair Color
Several factors influence the amount of melanin produced, including:
- Genetics: Hair color is largely determined by our genes.
- Age: Hair color can change with age due to a decrease in melanin production.
- Hormonal changes: Hormones can also affect melanin production, leading to changes in hair color.
- Exposure to sunlight: Sunlight can stimulate melanin production, leading to a darker hair color.
Hair Dyes and Melanin
Hair dyes work by either adding color to the hair or by changing the existing melanin in the hair.
- Permanent hair dyes typically contain chemicals that permanently alter the melanin in the hair.
- Semi-permanent hair dyes deposit color onto the hair shaft, but do not change the melanin permanently.
- Temporary hair dyes simply coat the hair with color and wash out with the next shampoo.
