Ever wondered why different people are born with varying colors of hair? The question has been there in our minds forever now. The presence of two types of melanin- eumelanin and pheomelanin, causes the hair color.
The amount of eumelanin in the hair follicle determines how light or dark the pigmentation would be. That is, more eumelanin causes darker hair color, while a small amount of it causes a lighter hair tone.
Hair color, though a genetic symptom, depends on the level of pigmentation due to the melanin, which may change over time as a result of aging, and other biological disorders.
Artificially, in recent times, hair shade can be changed by a person himself and is called hair coloring. Hair coloring is a process of transforming the natural color into a shade that the person desires for.
Genetically Determining The Hair Color
The theory of genetics and hereditary explains well the reason behind the hair shade of each organism. According to genetics, we already know, 23 pairs of chromosomes control the basic traits of an organism. Similarly, two gene pairs control the pigmentation of the hair.
Explaining The Phenotypes
The phenotypes mentioned above describe and explain why an individual has either a brown or blonde hair color. The brown hair shade, firstly, in this case, is dominant over the blonde. It proves why the majority of the population has brown colored hair. However, when a homozygotic pair crosses over with a heterozygotic one, the offspring has a 50% probability of being a blonde.
Similarly, the non-red allele here is the dominant one. Being recessive, the red allele is suppressed by the non-red allele in the heterozygotic condition. During the homozygotic condition present in one parent, the chances of having a red trait are 50%. The Punnett square determines the probability of traits.
Types Of Natural Hair Colors
Alterations Of Hair Color – Naturally And Artificially
Due to several medical and biological disorders, any individual may experience a change of hair color.
Malnutrition is yet another cause that leads to a change in hair tone. These are natural causes.
Artificial factors include hair, coloring, and dying.
Classification of hair shade can be categorized into permanent and semi-permanent.
- Permanent Hair Colour:
This process of dying involves the permanent alteration of the natural structure of the hair follicles. Firstly, the hair is treated such that it loses the natural texture, shade off the cuticles. The next step involves drying the hair with the desired synthetic shade. Finally, retentivity, even though permanent, is less, and natural hair can be seen growing from the roots. To maintain the dye, constant hair therapy is required to be followed.
- Semi-Permanent Hair Color:
This process of dying involves a temporary alteration of the natural structure of the hair follicles. Unlike the permanent hair colors, these last only up to six to eight weeks. Moreover, these are less harmful to the hair.
Should You Be Using It At All?
Rigorous studies and investigations showed that hair dyes are not suitable for organisms and contain cancer-causing ingredients. Thus it is advisable not to use hair dyes.