Sun and photo-aging
The sun plays a major role in our daily lives. It boosts morale, regulates our internal clock, promotes vitamin D synthesis...... but it is the skin's number one enemy! Indeed, in addition to cancers caused by repeated sunburn, it is the first exogenous aging factor: it is photo-aging.
The skin undergoes natural, chronological ageing, to which are added the effects of exposure to the sun, which precipitate and aggravate skin sagging. Indeed, the sun is the primary cause of aging among all environmental factors. The signs of this photo-aging are found in the areas most exposed to the sun: the face, neckline and hands.
UV rays create oxidative stress in the dermis altering fibroblasts. The latter will stop producing the components of the cellular matrix but will produce enzymes that are at the origin of collagen degradation. The hyaluronic acid naturally present in the dermis is also destroyed by UV rays.
Photo-aging is mainly reflected by:
- Brown spots or hyperpigmentation: increase in melanin on the skin leading to pigment disorders
- Solar elastosis: loss of firmness due to the degradation of collagen and hyaluronic acid
- Sagging of the dermis-epidermis junction that creates the appearance of wrinkles