Vegetable oils and fats have been used for nutrition and health for centuries. It is still the case that more than half of the world’s population produces and uses these fats and oils locally. Due to their fantastic skin care properties, availability and low cost, these natural oils and fats are immensely popular as skin moisturizers. They protect the skin and make the skin resistant to environmental influences. Many types of vegetable oils are used and new ones are added every month.
These natural oils are also receiving more attention in our regions because of their numerous benefits. The value lies in the so-called bioactive components of the fat or oil with a demonstrable effect on the skin (for an overview, see Sarkar 2017 and Vaughn 2018, among others). In contrast to mineral oils, natural oils and fats are able to use the components as building blocks in the formation of a healthy epidermis. In addition to emollient qualities, natural oils and fats possess components with antimicrobial and antioxidant properties. Many varieties have great potential in skin repair and maintenance of healthy skin.
There are many mechanisms involved in skin healing and hydration, but in this text we focus on two ways in which the plant oils function: repairing the skin barrier and moisturizing the skin. The role of a natural oil is to properly hydrate the skin and therefore a moisturizing plant oil should be the basis of any skin care product.
Natural oils and fats moisturize the skin by penetrating the stratum corneum, the stratum corneum layer of the epidermis. This stratum corneum consists of 15-20 flat thin layers of dead skin cells. There are various causes that cause openings or tears in the stratum corneum, such as aging, lifestyle, environmental influences, wrong skin products and incorrect use of the products. The figure below shows how natural oils and fats can restore the skin.
Restoring the skin barrier
Several studies have shown that natural oils with a high content of polyunsaturated fatty acids (especially linoleic acid) and a low percentage of oleic acid (a monounsaturated fatty acid) can best penetrate the skin and restore its barrier function. Conversely, oils high in oleic acid can irritate the skin and do not restore barrier function. For example, sunflower oil has been shown to quickly restore the barrier function of damaged skin. A good quality sunflower oil consists of more than 60% linoleic acid. When olive oil was tested on damaged skin, barrier function did not recover and trans-epidermal water loss worsened. This does not mean that only natural oils with a high content of linoleic acid should be used on the skin. But it does mean that if you want to choose a good moisturizer, it’s a good idea to choose a natural oil that is high in linoleic acid and low in oleic acid. Some good oils are sunflower seed, rosehip, sacha inchi, cactus and hemp seed.
It is worth noting that coconut and jojoba are low in linoleic or oleic acid. However, there is evidence that jojoba and coconut can reduce moisture loss from the skin. Apparently other mechanisms are at work here. Jojoba is actually a wax, so it functions differently on the skin. Jojoba resembles human sebum and is able to maintain an occlusive layer on the skin. In combination with another plant oil such as argan, rosehip, sacha inchi and hemp seed, jojoba is a top product for the skin.
For example, the properties and function of each natural oil or fat should be determined. For example, specific effects of various natural oils have been demonstrated. For example, sweet almond oil has been found to reduce the effect of skin aging caused by UV rays and slow down the aging process. Argan oil (Argania spinosa) improved skin hydration in postmenopausal women by restoring barrier function and reducing moisture loss. Argan oil was also taken in the study and that fact alone turned out to be a factor in skin repair!
In short, natural oils and fats function in a number of ways, two of which are highlighted in this article. They penetrate the stratum corneum, restoring the barrier function, minimizing water loss and using the ingredients as a building block for healthy skin. In addition, these oils form an occlusive layer so that the skin can protect itself well. Choose a plant oil with a high content of polyunsaturated fatty acids (especially linoleic acid) and a low percentage of oleic acid (a monounsaturated fatty acid), so that it can best penetrate the skin and restore the barrier function.