This is a non-essential omega-9 unsaturated fatty acid. Being non-essential, it is not required in our diet and can be synthesised by our body from stearic acid. The more the oleic acid content of the oil, the richer and heavier the oil. Oils rich in oleic acid are excellent moisturisers making them especially suitable for dry skin. They form an occlusive barrier on the skin, thus locking in moisture and reducing trans-epidermal water loss (TEWL).
The sebum secreted by the sebaceous glands in our skin also contains oleic acid, however too much is not necessarily good for oily acne-prone skin. Oils with a high oleic acid to linoleic acid ratio can make the sebum thicker, resulting in congested or blocked pores, whiteheads, blackheads and exacerbating some forms of acne. Individuals with conditions like rosacea or seborrhoeic dermatitis may also find that high-oleic acid oils exacerbate these problems.
This is an essential omega-6 unsaturated fatty acid. As it is essential, our body cannot synthesise it and we must include it in our diet. It is indispensable for humans and lack of it can cause deficiencies. With regards to the skin, lack of linoleic acid causes dry skin which can appear scaly with an unhealthy complexion. The barrier function of the skin is compromised and trans-epidermal water loss increases. The nails may tend to crack, there might be an increase in hair loss and the sebaceous glands may experience cornification disorders.
These consequences of linoleic acid deficiency prove how important this fatty acid is for our wellbeing and for the health of our skin.
Linoleic acid prevents barrier and cornifications disorders, reduces TEWL and increases skin moistness. Partly due to its anti-inflammatory properties, it markedly accelerates tissue repair and regeneration after trauma such as sun burn, dermatoses and other burns.
Unlike oils rich in oleic acid, high-linoleic acid oils tend to be thinner and lighter. They nourish the skin but are not as effective as high-oleic acid oils as moisturisers for dry, delicate skin, unless the skin was initially dry due to trauma or linoleic acid deficiency.
Like oleic acid, linoleic acid is also a component of sebum, but because it is much lighter than oleic acid, it can help thin the sebum in oily or congested skin. It has been found that individuals who tend to suffer with blocked pores or acne-breakouts tend to have sebum composed of a lot of oleic acid and little linoleic acid. This thicker, firmer sebum is more irritating, contributes to blocked pores, whiteheads, blackheads, pimples and exacerbates acne. By redressing this imbalance and increasing the linoleic acid content, the sebum is not as irritating or thick and flows freely from the pores, thereby reducing the incidence and severity of the above mentioned problems.
Present as alpha-linolenic acid (ALA), an essential omega-3 fatty acid and gamma-linolenic acid (GLA), an omega-6 unsaturated fatty acid. Although GLA is not itself an essential fatty acid due to it being synthesised by our body (not our skin) from linoleic acid, GLA deficiency can occur as a result of poor linoleic acid intake or in disease states wherein there is excessive consumption of GLA metabolites.
Both GLA and linoleic acid belong to the omega-6 family of fatty acids and are amongst the most important lipids for the maintenance of healthy skin and alleviation of skin disorders. They are essential for maintaining moisture, suppleness and smoothness as well as preventing disorders of the skin. Just like linoleic acid, a deficiency of GLA can cause a plethora of problems for the skin since they are responsible for maintaining the integrity of cell membranes. Skin cells with a healthy membrane keep moisture in and toxins out, thus improving elasticity, reducing sensitivity and minimising trans-epidermal water loss.
deficiency can result in skin which is scaly and dry and which sheds more frequently than normal, the micro-capillaries within the skins layers tend to be weak and rupture easily, water loss from the skin increases and the barrier function of the skin breaks down. Furthermore, other important chemicals produced from GLA, which are responsible for anti-inflammatory activity, wound healing and promoting blood flow may be absent or present in insufficient concentrations.
This is why skin conditions such as eczema, dry skin and dermatitis can sometimes be attributed to insufficient GLA or linoleic acid in the skin and why oral consumption or topical application of GLA has been found to be effective in treating these and other conditions such as acne and sunburn.
A saturated fatty acid. This amino acid is used to synthesise oleic acid in our body. Its primary benefit in natural oils is as a surfactant, allowing grease on the skin to mix with water for keeping skin hydrated and as a cleanser in the case of jojoba oil.
Stearic acid and palmitic acids are members of a group of free fatty acids (FFAs). It has been suggested that FFAs contribute to the acidificaton of the stratum corneum, otherwise known as the epidermis or outer later of the skin. There is some evidence that the acid mantle of the stratum corneum is important for both its permeability barrier and antimicrobial defence properties.
A saturated fatty acid like stearic acid, this free fatty acid is also an important component of both the skin barrier and the acid layer of the skin. It is an effective skin cleanser due to its surfactant properties, and has shown to exhibit antioxidant action.
The latter may help to explain why aged skin has been found to contain less than 50% palmitic acid compared to normal skin, since the presence of free radicals prematurely age skin and antioxidants are the most effective agents for eliminating free radical formation and action.
Palmitic acid is also an efficient emollient, helping to reinforce the skins barrier for a smoother complexion.
This refers to a group of compounds normally obtained from our diet. The most widely consumed is is gamma-tocopherol, however it is alpha-tocopherol, the second most commonly consumed, that possesses the most biological activity.
Vitamin E is often added to skin care products due to its excellent antioxidant properties.
Antioxidants neutralize the oxidant effect of free radicals which are atoms with an uneven number of electrons. These unstable atoms are formed inside the body following exposure to harsh environments, pollution, smoking and the sun's ultraviolet rays. In an attempt to become stable, they steal electrons from neighbouring atoms, initiating a chain reaction and propagating free radical formation. When these free radicals start taking atoms from healthy skin cells, they can cause permanent harm to the tissue, damaging collagen and causing dryness, fine lines and wrinkles, therefore accelerating the signs of ageing.
Antioxidants neutralize free radicals and prevent cellular damage from occurring. They protect the skin from UV light or other environmental stresses, enhance the skins barrier function, increase the efficacy of sunscreens, reduce the severity of sunburn, help reduce TEWL and prevent and reduce premature ageing of the skin. In addition, the presence of vitamin E in oils or other skin care products slows down their degradation.
Although vitamin E is one of the most powerful antioxidants, our body is unable produce it, therefore we have to ensure we are getting enough in our diet or at least from products we apply to your skin.
This refers to a group of compounds that include retinol, tretinoin and provitamin A carotenoids amongst others. Retinol is normally acquired through consumption of animal food sources and the provitamins which are subsequently converted to retinol in the body are normally acquired though consumption of plant foods.
Vitamin A is necessary for humans and has several important functions. It is important for growth and development and for maintaining a healthy immune system thus allowing our bodies to fight infections. It is necessary for our eyes so we can distinguish colours and see in low light conditions.
Vitamin A is also plays an important role in correcting a range of issues affecting the skin and in this regard has been the subject of much scientific research.
A derivative of vitamin A, tretinoin was used to treat patients with severe acne and found to be very effective at improving their condition. With continued use, these patients experienced further benefits to their skin. Researchers discovered that these patients had less wrinkles and more collagen in their epithelial tissue. However, tretinoin also had certain drawbacks. Patients experienced side effects of tretinoin therapy and complained of dry, irritated and reddened skin. They also experienced sensitivity to sunlight after application of tretinoin on exposed skin.
Despite these side effects, tretinoin and some synthetic derivatives are still used as effective treatments for acne in patients unresponsive to other treatments but their use has been regulated by health authorities by classifying these potent agents as prescription only products.
Fortunately, retinol, a milder less irritating form of vitamin A was found to be almost as effective on skin, both for treating various skin conditions as well as a cosmetic agent to reverse the signs of ageing.
Continued research has found numerous benefits of vitamin A along with the processes by which it yields these benefits.
It has been found to be an effective cell-communicating agent, binding with various receptors to induce cells to revert to normal healthy behaviour. These cells may have been exposed to UV damage or other environmental damage causing them to lose their normal function, e.g. follicular keratin cells which make up the lining of pores not shedding in a timely manner causing them to build up and therefore enlarge pores. By inducing these cells to revert to their healthy behaviour, vitamin A can help reduce enlarged pores.
Vitamin A also binds with receptors to encourage sloughing of the epidermal cells, thus peeling off part of the top layer. At the same time, it increases the thickness of the dermis by increasing blood flow in this layer and stimulating the synthesis of collagen, a protein responsible for keeping skin firm and springy.
The net effect of this is smooth even, plump skin with fewer wrinkles.
Vitamin A helps reduce melanin granule clusters responsible for pigmentation spots.
By normalising circulation in the skin, it helps with wound healing, scarring and conditions such as rosacea. By repairing the cellular structure of the skin, it helps treat various skin conditions including eczema and psoriasis. By restoring the protective nature of the integument and due to its antioxidant activity, it minimises the risk of UV or other environmental damage and reverses some of the damage that has occurred.
Natural plant oils don't just contain the chemical constituents listed above. They contain numerous other beneficial ingredients, some in trace amounts yet so potent that they play a key role in making that particular oil unique.
This is in contrast to laboratory formulated cosmetics and moisturisers which contain just a fraction of the skin nourishing nutrients present in natural organic oils.