What lies behind the PP(-) skin typology?
What is the meaning of the term PP(-)?
Skin ageing PRONOUNCED
Oxidation Factor PROTECTED
Sebum Production LOW (-)
The "P" for Pronounced Signs of Ageing.
The first letter "P" indicates that skin ageing is well established. On mature skin, after the age of fifty, expression lines that appeared earlier (crow's feet at the corners of the eyes, frown lines...) become increasingly pronounced, with a loss of firmness at their root. Cellular degeneration continues, coupled with a reduction in the number and size of fat cells in the fatty tissue of the hypodermis, the deepest layer of the skin. This reduction leads to a loss of volume and firmness, which will hollow out the cheeks.
Furthermore, in women, at the time of menopause, deficiencies in oestrogen and progesterone exacerbate the chronological ageing of the skin. Indeed, oestrogens stimulated keratinocytes, the synthesis of hyaluronic acid and collagen, and inhibited the growth of hair follicles. However, with this abrupt drop in the secretion of female hormones, we observe an increased skin dryness, a modification of the barrier function and a loss of radiance.
The letter "P" for Protect against oxidation factors.
The letter "P" signifies that the skin is well protected against the sun's UV rays. Beyond these beneficial effects on mood or vitamin D secretion, excessive sun exposure is the main cause of premature skin ageing and the onset of skin cancers. Indeed, UVA rays can cause dermal changes especially in the elastic tissue, and UVB rays lead to epidermal damage. Activation of free radicals, alteration of the cell membrane, DNA modification... UV rays act differently within skin cells to generate damage, which can alter the cell's function, cause its death or provoke DNA mutations leading in the long term to the formation of cancerous cells. Thus, even though the skin has some defences against UV rays (melanogenesis, endogenous antioxidant system...), it is important to regularly apply a sufficient amount of a sunscreen product that is suitable for your skin type and sun exposure conditions, to ensure reasonable exposure while limiting risks.
The symbol "-" denotes Low sebum production.
The "-" indicates a reduction in the ability of the sebaceous glands to produce sufficient sebum (sebaceous hyposecretion), as well as a discrepancy in the synthesis of natural moisturising factors by keratinocytes, which give the skin the ability to retain water. Tightness, irritation, dehydration fine lines, redness, flaking, dull complexion... are characteristic of this skin type.
Indeed, this lack of lipids reduces the effectiveness of the hydrolipidic film. The skin then becomes vulnerable to all forms of aggression (UV rays, pollution, bacteria, etc.), triggering inflammatory reactions, and no longer prevents transepidermal water evaporation as effectively. Moreover, this alteration in the barrier function leads to a dysregulation of Langerhans cells (cells of the immune system), which begin to induce disproportionate inflammatory responses when they are overly stimulated.
Several factors can influence this low sebum secretion, leading to these disturbances: frequent washing, certain medicinal treatments, unsuitable skincare, seasonal variations, tobacco, UV radiation, genetics... However, although this skin type is more prone to wrinkle formation due to its less supple nature, it is conversely less susceptible to skin sagging given that its thinner epidermis suffers less from the effects of gravitational pull.