Shea butter to combat the signs of ageing.

The progression of age inevitably brings with it skin ageing. Signs of ageing begin to appear from the thirties onwards and are particularly noticeable on the hands and face.

• This is accompanied by structural and functional changes in the components of the extracellular matrix, such as collagen and elastin, with a decrease in their natural production. The skin then loses its elasticity and firmness, which promotes the appearance of wrinkles.

• Alterations in the amino acid composition of ageing skin can reduce levels of natural moisturising factor (NMF), thereby diminishing its ability to bind to water. Dehydrated skin becomes more fragile and promotes the appearance of signs of skin ageing.

• The rate of skin cell renewal slows down, resulting in a deteriorated skin appearance. Depending on the skin's characteristics, it can thin, thicken, or dry out. Wrinkles form around the eyes, lips, and forehead. Its defences against external aggressions also decrease, and the skin may show pigmentation spots.

The shea butter, a thick and yellowish butter produced from the nuts of the shea tree, is rich in fatty acids, tocopherols, triterpenic alcohols, cinnamic acid esters, and retinol. A well-known versatile skincare product in many African countries, it can also be applied to the skin to prevent and slow down the skin ageing process thanks to the numerous properties attributed to it.

• Nourishing

  The skin requires regular nourishment to slow down the ageing process. Shea butter contains a majority of fatty acids: stearic, linoleic, palmitic and arachidic. Oleic acid is a lipid that is part of the composition of sebum. It stimulates the production of sebum by the sebaceous glands. Its application strengthens the skin's protective barrier, which is itself composed of fatty acids, and ensures the balance of the hydrolipidic film.

  Vitamin F refers to the combination of two essential fatty acids: linoleic acid and linolenic acid. Thanks to its high fatty acid content, Vitamin F nourishes the epidermis and maintains the skin's barrier function.

  Shea butter will provide the necessary nutrients to the skin and form a film covering the epidermis.

• Regenerating

  To maintain its health and firmness, the skin regularly renews itself. This process of cellular renewal slows down over time and the appearance of mature skin can quickly deteriorate.

  Typically, a vegetable oil contains less than 1% of unsaponifiables, primarily phytosterols and tocopherols. The content of unsaponifiables in shea butter is at least 4% and can go up to 10% (phytosterols, tocopherols, triterpenes...). A study has shown that triterpenes have a positive regulatory activity on collagen production. They help to inhibit matrix metalloproteinase 3 (MMP-3), which is responsible for the degradation of type III skin collagen. Further studies are still needed to better understand the mechanisms of action of these triterpenes.

  Furthermore, the triterpenes in shea butter contribute to cellular renewal by increasing the thickness of the epidermis. These results show that triterpenes play a part in the resistance and protection of the skin barrier.

  Vitamin A, found in shea butter, stimulates the production of collagen and elastin which helps the skin maintain its elasticity. It smooths wrinkles and fine lines and prevents skin sagging.

  A clinical study was conducted on 49 volunteers who applied pure shea butter twice daily. For 75% of the volunteers, a reduction in wrinkles and an improvement in skin suppleness was observed.

  Thanks to its richness in vitamins and its content of unsaponifiables, shea butter will help the skin regain its suppleness and elasticity, the hallmarks of youthful skin.

• Antioxidant

  The sun is a primary factor in skin ageing. Ultraviolet (UV) radiation breaks down elastin and collagen fibres. These non-functional tissues accumulate in the dermis, leading to the formation of wrinkles. Vitamin E, or tocopherol, found in shea butter, protects against external aggressions such as UV radiation and chemical pollution. Vitamin E is capable of donating an electron to a free radical without becoming unstable. The free radical is stabilised, less reactive, and the oxidation cascade of molecules is halted. This is beneficial in preventing oxidative stress, which is at the root of skin ageing.

  Shea butter is rich in cinnamic acid esters, phenolic substances that strongly absorb UV rays between 250 and 300 nm. An experiment has shown that shea butter, in synergy with a photoprotective treatment, can increase the absorbance of UVB rays. UVB rays can produce free radicals that are responsible for skin ageing.

  Shea butter possesses antioxidant properties that combat free radicals and environmental factors responsible for premature skin ageing.