Melanin

introduction

Melanin is a color pigment and is therefore responsible for our skin color, hair color and the color of our eyes.Depending on how much melanin these structures contain, we have a lighter or darker skin type. In addition to melanin, heredity also plays a role here.
Melanin is made from an amino acid with the help of UV rays and a hormone in our body.

Function of melanin

At Melanin it is a pigment that is used for Coloring for skin, Hair and the color pigments in the eye.
A distinction is made between two different melanins in humans. There is the brown-blackish eumelanin and the yellowish-reddish pheomelanin. As a rule, the melanins occur as mixed forms. The content and ratio of the two melanins play an important role in the color of hair.

The production of melanin is increasingly stimulated by the sun's rays and a hormone that stimulates melanocytes. The pigment has an important protective function, especially in human skin. Due to the brownish to black color pigment, the epidermis is protected from damaging UV rays protected from the sun.
The sun's rays cause more melanin to accumulate in the skin. The more melanin is produced by the melanocytes, the darker the skin color appears. This is eventually transferred to keratinocytes (mainly skin cells that occur) and stored in them. The melanin surrounds the cell nucleus (which is also the genetic material that DNA, contains) the keratinocytes around to protect them from the sun's rays, which can change cells.
UV rays can damage the genetic material, which can lead to cells degenerating and cancer. Melanin therefore acts as a kind of natural "UV protection". This UV protection already exists a short time after the skin has been exposed to sun rays and melanin production has increased.
Melanin does not always have to be completely regenerated, however, as some preliminary products are already present in the skin, so that melanin can be introduced into the keratinocytes relatively quickly in the event of brief exposure to the sun.
However, this so-called instant pigmentation fades again after a few days, whereas with late pigmentation of the skin due to prolonged exposure to the sun, the tan lasts longer and at the same time offers longer protection.
Furthermore, melanin takes on the coloring of the eyes iris. The different eye colors arise depending on the level of melanin in the iris. The inheritance of genes also plays a role here. Lack of pigments in the iris and in the Choroid the blood vessels shine through and the classic image of Albinism (Red eyes).

Melanin in the skin

Melanin is the brownish to black one Color pigment in the skin of the human. There it is formed in certain cells called melanocytes. The production of melanin is stimulated by the UV rays that are in the sun and by a hormone that is produced by the body itself.
There are two different forms of melanin in the skin. Phaeo- and eumelanin determine the skin color of the respective person due to their content. With fairer skin types, there is a higher proportion of Phenomelanin in the skin. Darker skin and hair types have less phenomelanin in the skin. Melanin plays an important role in the skin. It is produced under the action of sun rays or from precursors and is stored in certain cells of the skin, the keratinocytes.
The melanin covers the cell nuclei of the skin cells like a protective coat. This protects the nuclei of the cells from the dangerous rays. They contain the information of the genetic material that can be damaged by the radiation and the development of cancer cells is promoted.
If there is a lack of melanin in the skin due to a genetic defect or a production disorder, those affected have very light skin. This then affects all pigment-containing cells as well as the hair and eyes. The appearance is known as albinism.
On the other hand, it can also lead to an overproduction of melanin. The skin then shows more brown spots of different sizes. These can be moles, birthmarks, and freckles. With these skin changes there is also an increased risk that they will degenerate and become too Skin cancer (malignant melanoma).

For more information, see: Skin color - skin types and effects, What skin type are you?

Melanin in the hair

What hair color a person has is largely dependent on genetic factors and the melanin content in the hair cells. The ratio of eu- and pheomelanin determines the hair color.
Eumelanin contains a lot of black-brown pigment, while pheomelanin contains a lot of red pigment. Accordingly, lighter hair types have little eumelanin and a lot of pheomelanin. Darker hair types have exactly the opposite relationship. Similar to blonde hair types, redheaded people have very little eumelanin and even more of the pheomelanin.
The individual mixture of these different pigments creates different hair colors that can also combine different colors. The melanin determines the hair color, but is not responsible for the hair structure. Gray hair is caused by the loss of the melanin content in the cells.

Melanin in the eyes

The pigment melanin is also contained in our eyes. There it is responsible for the different eye colors, depending on the type of composition and the strength of the pigments. Most newborns have bright blue eyes at birth because the color pigment has not yet been sufficiently produced.
The iris (rainbow skin) is initially still unpigmented and the color is therefore initially due to the pigment epithelium on the back of the iris. Only when the melanin-producing cells are stimulated is enough melanin produced over time to color the eye.
Genetic inheritance also plays an important role in the development of eye color. Depending on how much melanin accumulates in the iris, eye colors can be gray, blue, yellow, green, brown or even black. The eye color mostly corresponds to the skin type. Blond-haired and lighter skin types tend to have blue eyes, dark-haired mostly brown eyes.

Further information can be found at: How does eye color come about?

Melanin in tablet form

Melanin is also available as a man-made substance in tablet form. The amino acids that the body needs to produce melanin are often enriched in the tablets. In this way the production of melanin can be stimulated by the body.
The tablets are most commonly used for Support of getting tanned of the skin. By supplying melanin as tablets, the tanning of the skin should take place more quickly and naturally. Furthermore, one hopes for one's own through the tablets Keep hair color upright. They are also sold as a product against gray hair. There are different opinions about the tablets regarding their effectiveness.

Melanin against gray hair

Gray hair occurs due to a lack of melanin in the hair cells. The hair color fades with increasing age or with a reduced production of melanin. However, other factors also contribute to the graying of the hair, such as hyperacidity, constant coloring in the previous period and psychological stress.
There are various remedies against gray hair that stop it from turning gray or allow the hair to reappear in its original color. So there is for example Re-pigmentation creamsthat replicate the melanin in hair. They react with the air bubbles in the hair that have accumulated there instead of melanin and then make the hair look pigmented again.
Melanin is made from the Amino acid tyrosine by the Tyrosinase enzyme manufactured. It is assumed that with age there is an increasing lack of tyrosine and the important enzyme, which can also be damaged by hydrogen peroxide, for example. So there are different ones Means that contain amino acids to restore melanin production. Furthermore, there are approaches that Administer enzyme tyrosinase to maintain melanin production.
The key to fighting gray hair is melanin. However, so far the researchers have no effective method found yetto maintain the melanin content in the hair even in old age. There are approaches that hair care products that contain substances similar to the hormone melanin can stimulate melanocytes to produce melanin. Previous products against gray hair only cover the hair and only let the hair reappear in color for a short time.