Is avocado oil comedogenic?

Derived from cold pressing of avocado kernels, theavocado oil is rich in vitamins and fatty acids, giving it nourishing and protective properties. This oil is used for skin massage or as a natural ingredient in certain cosmetic treatments (INCI name: Persea Gratissima (Avocado) Oil).

It presents itself as a thick, oily liquid ranging in colour from green to brown. Avocado oil has a distinctive mild scent, and its texture is quite rich. When the temperature drops (below 20°C), the oil solidifies and becomes almost solid.

This ingredient also has benefits for the hair. Nourishing, it coats the hair fibre to keep it protected from external aggressions and prevents the appearance of split ends and white hairs. After application, the hair is strengthened and appears shinier.

An ingredient is said to be comedogenic if, when applied to the skin, it blocks the pores and promotes the formation of an "occlusive" film. This prevents the normal evacuation of sebum and contributes to the appearance of blemishes: comedones. If you have acne-prone skin, applying a comedogenic ingredient is likely to exacerbate this skin infection.

To determine whether an oil is comedogenic or not, one can refer to its comedogenicity index, which ranges from 0 to 5. In theory, an ingredient with an index of 0 is considered non-comedogenic. From 1 to 2, it is deemed slightly comedogenic. An index above 3 indicates that the ingredient is comedogenic. This index is calculated to assess the occlusive potential of an ingredient.

However, it is important to note that the comedogenicity of an active ingredient does not necessarily lead to the appearance of skin imperfections. Similarly, the application of a skincare product containing a comedogenic ingredient does not always result in spots. This depends on its concentration in the product. Finally, the risk of developing imperfections after using a comedogenic ingredient also depends on each person's skin type.

Generally, it is advisable not to exceed a comedogenicity index of 2 for oily skin types. This type of skin is indeed more prone to blemishes and the appearance of spots. Normal to dry skin types, on the other hand, can tolerate oils with an index of up to 3.

Various factors influence the comedogenicity index:

• Oxidation Sensitivity : Vegetable oils are often defined by their oxidative potential. When the fatty acids that make up the oil tend to degrade, this can affect the quality of the product and increase its comedogenicity index. Several factors can trigger this oxidation, such as the oxygen in the air, light, interactions with the container, or even heat.

• Freshness : Over time or when improperly stored, vegetable oils can oxidise, which may alter their comedogenicity index.

• The quality of the oil : a virgin oil derived from a cold pressing extraction method retains the active substances found in the raw materials, such as fatty acids and vitamins. This process does not require chemical treatment or heating the oil to a high temperature, which could destroy certain fatty acids in the vegetable oil and lead to the formation of new compounds, not necessarily beneficial for the skin. Thus, virgin vegetable oils often have a lower comedogenicity index.

• The rate of penetration of vegetable oil into the epidermis : a thick and greasy oil is difficult for the skin to absorb, which increases its occlusive nature. On the contrary, the more the oil has a strong affinity with the skin, the easier it penetrates. These oils are referred to as dry oils and are primarily composed of omega-3 and omega-6. Greasy oils, on the other hand, tend to contain omega-9.

The vegetable oil of avocado is non-comedogenic. It easily penetrates the skin tissues without leaving a greasy film on the skin. Furthermore, it has a low oxidative potential due to the presence of Vitamin E, an antioxidant, which it contains, making it stable.

Given that the freshness of the oil plays a role in determining its comedogenicity index, it is essential to use fresh avocado oil. After opening, do not keep the oil for more than six months and store it in a place protected from light in a tightly sealed bottle. It is also advisable to ensure that the avocado oil included in your care has been obtained by cold pressing and not by extraction with a solvent.

• HEREDIA J. B. & al. Fatty acid profile, total carotenoids, and free radical-scavenging from the lipophilic fractions of 12 native mexican avocado accessions. Plant Foods for Human Nutrition (2019).

• ORTIZ-VIEDMA J. & al. Avocado oil: characteristics, properties, and applications. Molecules (2019).