Stretch marks are signs that appear on the skin as a result of the breakdown of the elastic fibers of the epidermis. They can be either purplish-red or white in color and involve both men and women. Knowing their causes is important to prevent them from arising, or to reduce their visibility.
The atrophic striae, more commonly known as stretch marks, they are skin lesions which represent a very widespread imperfection, both in women and in men. These blemishes depend on different factors and appear as slightly sunken strips of the epidermis.
Their color can vary from red to white and can appear mainly on the hips, thighs, belly and breasts. Knowing the causes of these signs helps to intervene on your body both to prevent them from emerging, and to reduce them and make them less visible.
The causes of stretch marks
Stretch marks are mainly related to very rapid changes in body weight, but not only. These imperfections are also linked to elements such as the use of corticosteroid-based drugs, which greatly reduce the elasticity of the skin, or to stress. In some rarer situations, stretch marks are caused by previous pathologies.
What unites them in any case is that they are real scars resulting from fractures in the supporting structures of the epidermis.
How stretch marks arise
To understand how these signs emerge, it is necessary first of all to start with an understanding of the structure of the epidermis.
The skin is made up of three layers:
- epidermis: the outermost layer that covers and the melanocytes, the cells responsible for the synthesis of melanin, that is the pigment that colors the skin;
- dermis: it contains nerves, blood vessels, sweat glands and hair structures. This area is rich in connective tissue, collagen and elastin.
- Hypodermis: represents the deepest part that contains the subcutaneous fatty tissue.
When the skin is subjected to more or less severe cases of stress, it goes through three different moments.
- Inflammatory phase: when the skin tissue is stressed and is unable to sustain the effort, discomfort, burning and itching are felt. Traction damages the fibroblasts (ie the skin cells that produce collagen and elastin) and above all alters their activities.
- Regenerative phase: the activity of the fibroblasts is restored, but the elastin fibers remain entangled, while the collagen fibers break. At this time the first reddish streaks begin to appear which are synonymous with skin trauma and poor hydration.
- Healing phase: the fracture in the dermis heals and the skin fills it with a solution consisting of fibrous tissue, the scar. This, however, does not have the characteristics of healthy skin, but is hypopigmented. In this phase, the stretch marks take on the white color which indicates that the phenomenon is now in a degenerative phase and therefore irreversible. These signs, in addition to being visible, are also perceptible to the touch.
What the scars depend on
There predisposition to the formation of stretch marks is related to amount of collagen and elastin present in the skin, which if it is very low determines a very high possibility that these imperfections emerge, in addition to that of wrinkles. Unlike what one might think, stretch marks can emerge in both women and men.
The link with stress determines the fact that the cortisol, the stress hormone, in particular moments of not only physical but also psychological tension, reduces the elasticity of the skin. By the same principle, the application of local ointments containing cortisone also makes the skin thinner and increases the likelihood of these streaks appearing.
Also some diseases that cause alteration of the collagen structure (such as Marfan Syndrome) can cause an increased risk of developing stretch marks
The main causes of stretch marks
Stretch marks can have different colors depending on the scarring phase the skin is facing.
The high weight and the accordion effect, or the weight loss followed by a quick recovery of the kilos, can give rise to stretch marks, but they are the only causes.
- The treatments based on corticosteroids, as mentioned before, they cause a reduction in skin elasticity.
- During puberty, when it starts breast form, the tissues responsible for this growth can be subjected to tension and thus lead to the formation of scars.
- The youthful stretch marks they can also arise between the ages of 14 and 18 involving not only the breasts, but also the thighs, abdomen and buttocks.
- Stretch marks can arise more easily in people who are affected by disorders of the adrenal gland, which causes an increase in cortisol in the blood and therefore a loss of elasticity and endurance of the efforts to which the skin is subjected. Swings in cortisol are mainly related to adolescent development, menopause and stress.
- Also during pregnancy There is a very high probability that stretch marks will form at the height of the thighs, lower abdomen and breasts: this is because during the nine months the body is subject to continual changes and the tissues are particularly stressed.
- Some pathological conditions they can lead to an increased risk of developing stretch marks, such as Cushing’s, Marfan’s or Ehlers-Danlos’s syndrome.