Where is the skin located?
The skin forms an effective barrier between the organism and the environment, protecting against the invasion of pathogens, chemical and physical attacks, as well as the uncontrolled loss of water and dissolved substances (salts, metabolites, etc.). It also helps with thermal insulation, temperature regulation, and as a receptor for some senses.
What is the skin?
The epidermis is the top layer of the skin and is made up of epithelial cells. It does not contain any blood vessels. Its main function is protection and participation in the maintenance of the homeostasis. It consists of four types of cells: keratinocytes, melanocytes, Merkel cells and Langerhans cells. The main type of cells that make up the epidermis are keratinocytes, which produce keratin. Keratin is a fibrillar (filamentous) protein that makes up the extracellular space of epidermal cells. Millions of keratinocytes are shed every day. A large part of the skin is keratinized and therefore waterproof, otherwise when bathing for example, some of water would enter freely through the layers and the human body would swell. All the microorganisms from our unique skin microbiome live on the surface of the epidermis. A healthy epidermis also ensures moisture retention inside the skin.
What are the main functions of the skin?
Healthy skin is a dynamic system that flexibly adapts to changing environmental conditions, such as:
- adapts heat loss to the outside temperature;
- regulates water loss depending on temperature and humidity – “under normal conditions” between 0.5 and 1 liter per day;
- eliminates salts (through the sweat glands) and lipid substances (sebum, “lipid mantle of the skin”);
- serves as a barrier against foreign substances and microorganisms, including control of the pH level of the skin surface;
- builds individual protection against stress caused by UV light;
- protects against mechanical stress;
- transmits pain, temperature and tactile stimuli (touch) through the nerves.
What skin types are there?
Each person is unique, and this does not only apply to character. There are many systems aimed at characterizing and classifying different skin types, but scientists have not reached a consensus. Broadly speaking, we can divide skin types into six types:
“Sensitive skin” is not exactly a skin type, but rather a symptom caused by various factors. People tend to describe their skin as “sensitive” if it often reacts with redness, itching, burning, or dryness to topical skin care products. The causes of this condition can be a hidden skin disease, allergies, contact with irritants in certain products or incorrect use of cosmetic products.
How to take care of your skin?
+ Apply sunscreen every day.
+ Monitor the type and size of your moles and freckles – if they grow fast, have an irregular shape or itch, it’s best to consult a dermatologist.
+ Use products that meet the needs of your skin. If you are not sure visit Personal Diagnostics by L‘ali.
+ Don’t use harsh exfoliating products more than once a week, and even then don’t use force.
+ Wash your face with appropriate products every morning, at night before going to bed and after sweating.
+ If you have sensitive skin, wash the cleansing products off your face with lukewarm water, even if you only use micellar water.
+ Drink enough water (according to weight, about 30 ml / 1 kg / day).
+ Diet and exercise may not seem directly related to healthy skin, but they are. Exercise as much as possible and eat a varied diet.
+ If you have any concerns about your skin or scalp, see a dermatologist.
This is an editorial prepared especially for you by L‘ali.
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