Beauty has no age, and more and more people wish to shine and keep their face looking young and radiant. However, the myriad of skin-rejuvenation products on the market can be daunting. Do all these cosmetics have the same effect? Of course not. So we have to ask ourselves: Which substances should be included in an anti-ageing product? What should be considered the star ingredient?
Human skin undergoes a natural ageing process over time. Unlike other organs, the skin is continuously exposed to environmental factors, such as radiation and pollution, which cause it stress.
Many histological and structural studies have revealed that, over time, the skin undergoes morphological changes which are characterised in particular by the loss of hydration and collagen, its main structural protein. This causes the epidermis and dermis to thin, which leads to changes in texture and flaccidity, which mainly take the form of wrinkles and changes in pigmentation. The skin becomes more fragile and vulnerable.
The fact that changes in the skin are the most visible signs of ageing means that their appearance has a significant emotional and psychological impact on our quality of life and on society in general. But that’s not all. At the clinical level, aged skin also has a negative impact, in terms of wound healing, vascular fragility, and influence on developing diseases such as cancer.
To mitigate these effects and in order to rejuvenate the skin, anti-ageing preventive treatments have been proposed. It has been demonstrated that the results are significantly better if the treatment includes topical application of retinoic acid (tretinoin, vitamin A) or its derivatives, retinoids such as retinol (ROL), retinol esters (retinyl palmitate) or retinaldehyde.
How does retinoic acid or its derivatives act on the skin?
Their success is due to the fact that they act on the main skin cells:
- They stimulate keratinocyte proliferation by increasing the thickness of the epidermis and reducing the size of pores.
- They stimulate dermal endothelial cell proliferation by increasing dermal vascularity.
- They activate dermal fibroblasts by increasing ECM production (type 1 and 3 collagen, fibronectin and elastin).
- They inhibit collagenases and, as a result, prevent collagen destruction.
- They improve homeostasis of the epidermis and dermis.
- They regulate sebum production.
- They induce hyaluronic acid production and stimulate gene expression of the three forms of hyaluronic acid synthase (HAS).
- They normalise melanogenic activity.
- They act as powerful antioxidants.
Their multifunctional activity enables them to be used to prevent or reverse substantial skin problems. Hundreds of clinical studies and measurements confirm their extraordinary ability to increase skin hydration and collagen levels, reduce wrinkles, combat acne, improve skin texture, unify skin tone and reduce hyperpigmentation. It is also important to highlight the fact that retinol and its derivatives are photosensitive and photosensitizers. As such, sunscreen use is recommended.
The effectiveness and tolerability of retinol depends on the dose applied. Topical retinoic acid is the one which provides the greatest anti-ageing effects. However, tolerance to it is limited, as it tends to cause irritation, a burning sensation, flaking and dermatitis. Its prescription and use must therefore be done under the supervision of a professional at all times. Retinyl palmitate and retinol are better tolerated and, as such, the level of treatment adherence is higher. Once applied, the body transforms them into retinoic acid. These are allowed to be sold to the public (as a cosmetic and cosmeceutical, depending on their purity and concentration). Nevertheless, these must be used with caution. Expert advice is recommended when using.
Despite the fact that there are very few studies comparing retinoic acid and retinol, some confirm that, while the magnitude of the effect of retinoic acid tends to be greater, retinol induces similar changes in the skin’s histology and the gene and protein expression. They typically evaluate hydration, reduction in fine wrinkles and unification of the skin tone on the cheeks and eye area.
When formulating a cosmetic with retinoids, it must be taken into account that the ingredients are easily oxidisable and are degraded with light, air, temperature, low pHs and time. The results of various studies show that its use combined with other vitamins (E and C) cause its degradation rate to be lower. New encapsulated forms have been designed not only to protect the active material from degradation, but also to obtain a controlled release, thereby decreasing the irritation but not the effectiveness. Given this, it is important to know its actual concentration. The application of 0.1-0.3% is considered to be a low, tolerable dose, while 0.5-1.6% is considered to be high. In terms of treatment time, this will depend on the purpose, dose and patient tolerance. It is a highly versatile active material which can be adapted to the skin type and treatment purpose. Examples of application protocol and concentration include: retinol at 1% for 12 weeks, 0.4% for 7 days on alternate weeks, or even 0.1% daily throughout the year.
Here at Neftis Laboratorios, where we always keep up to date with the latest cosmetic trends and developments, we are pleased to offer a wide range of products to help prevent and reverse skin ageing. We like to provide our customers with youth, health and radiance.