1) The Secret of Skin
The changes in skin color are mainly influenced by the following three factors.
1. The content and distribution of various pigments in the skin affect eumelanin: this is the main pigment that determines the depth of skin color, and its concentration directly affects the brightness of skin tone. Among black people, melanin granules are large and densely distributed; Among Asians and Caucasians, it is smaller and more dispersed. Pheomelanin: gives the skin a yellow to red color tone. Its content and distribution determine the warm and cool tone of skin color, for example, Asians usually have a higher content of brown melanin. Carotenoids and flavonoids: These are exogenous pigments derived from diet, such as carrots, pumpkins, and other foods rich in beta carotene, which can add a yellow to orange hue to the skin.
2. The content of hemoglobin in the blood of the skin is called Oxyhemoglobin: Oxyhemoglobin, which is a bright red color and abundant in the skin, can make the skin look more vibrant and healthy. Deoxyhemoglobin: Non oxygenated hemoglobin appears dark red or purple, and when its proportion in the blood is high, the skin may appear pale.
3. In addition to other factors, skin color is also influenced by blood circulation, oxidative stress, hormone levels, and environmental factors such as UV exposure. For example, ultraviolet radiation stimulates melanocytes to produce more melanin to protect the skin from damage.
2) The secret of pigmentation
Stains, medically known as pigmentation lesions, are a phenomenon of localized darkening of skin color. They can have different shapes, sizes, and colors, and have diverse origins.
Stains can be roughly divided into the following types:
Freckles: typically small, well-defined, lighter colored brown spots that primarily appear on the face and other skin areas frequently exposed to sunlight.
Sunspots or Age spots: These spots are large, ranging in color from brown to black, and are commonly found on the face, hands, and other areas of middle-aged and elderly people that have been exposed to sunlight for a long time.
Melasma, also known as “pregnancy spots,” typically presents as symmetrical dark brown patches on the face that are associated with changes in hormone levels.
Post inflammatory hyperpigmentation (PIH): This is a pigmentation formed due to increased pigment deposition after inflammation, commonly seen after acne or skin damage has healed.
Genetic factors contribute to the formation of pigmentation: Certain types of pigmentation, such as freckles, have a clear familial genetic predisposition. Ultraviolet exposure: Ultraviolet radiation is the main cause of various pigmentation, especially sunspots and melasma. Hormone levels: Pregnancy, contraceptive drugs, or endocrine disorders can all cause changes in hormone levels, leading to the development of melasma. Inflammation: Any factor that causes skin inflammation, such as acne, trauma, or allergic reactions, may trigger post inflammatory pigmentation. Drug side effects: Some drugs, such as certain antimalarial drugs and chemotherapy drugs, may cause pigment deposition. Skin color: People with darker skin tones are more prone to excessive pigmentation.