Is hibiscus oil comedogenic?

Thehibiscus vegetable oil is recognisable by its sweet and light scent, its golden yellow colour, and its fluid texture. It is used in the composition of many skin and scalp care products under its INCI name "Hibiscus Sabdariffa Seed Oil". This oil is extracted from hibiscus seeds by cold pressing. The absence of chemical treatment and the use of a moderate temperature in this process ensure that the active ingredients are not denatured and retain all their benefits.

Thehibiscus oil owes its nourishing and protective virtues to its richness in linoleic acid (omega-6) and oleic acid (omega-9). These fatty acids indeed contribute to maintaining the elasticity and suppleness of the epidermis. Linoleic acid, in particular, stimulates the synthesis of ceramides, lipids naturally present in the skin and ensuring good cohesion between the cells of the epidermis. Oleic acid, on the other hand, is part of the composition of the skin's hydrolipidic film , a film that limits its dehydration and protects it from external aggressions (wind, temperature variations...). Finally, hibiscus vegetable oil is particularly rich in vitamin E, a natural antioxidant that fights against premature skin ageing by eliminating free radicals. It thus constitutes a choice ally in preventing the appearance of wrinkles and fine lines.

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. These take the form of blackheads or whiteheads. 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. Theoretically, 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 the skin type of each individual.

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 can alter their comedogenicity index.

• The quality of the oil : a virgin oil derived from a cold-press 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. Conversely, the more the oil has a strong affinity with the skin, the more easily it penetrates. These oils are referred to as dry oils and are primarily composed of omega-3 and omega-6.

Hibiscus oil is non-comedogenic. It is easily absorbed by the superficial layers of the skin and scalp and does not leave a greasy film upon application. This is due to the omega-6s present in its composition. Hibiscus oil is indeed a dry oil. Furthermore, it has a low oxidative potential due to the presence of vitamin E, an antioxidant it contains, which makes it stable.

As previously mentioned, comedogenicity also depends on the quality of an ingredient. It is advisable to ensure that the hibiscus oil included in your skincare has been obtained by cold pressing and not by extraction with a solvent, and to store it away from light in a tightly sealed bottle.

• FAKOYA A. & al. Free radical scavenging and antigenotoxic activities of natural phenolic compounds in dried flowers of Hibiscus sabdariffa L. Molecular Nutrition and Food Research (2005).

• HEINRICH M. & al. Hibiscus sabdariffa L. - a phytochemical and pharmacological review. Food Chemistry (2014).