Is safflower oil among the so-called comedogenic vegetable oils?

An oil is referred to as comedogenic when its application on the skin can potentially lead to the formation of comedones. These are oils with a thick and greasy texture that can clog the skin's pores. The sebum can then no longer flow properly, and pimples, blackheads or whiteheads may appear. Individuals with acne-prone skin are particularly sensitive to comedogenic ingredients, as their topical application may exacerbate their skin problem.

The comedogenicity of a vegetable oil is assessed on a scale of 0 to 5. A rating of 0 means that the ingredient is non-comedogenic and a score of 5 indicates a highly comedogenic effect. This classification was established in 1983 by Dr. MORRIS and his team based on studies on rabbit ears. The appearance of the follicles, the presence of hyperkeratosis, and the manifestation of inflammation after use were particularly observed. The principle of comedogenicity was subsequently re-evaluated in order to be more suited to human skin. Several criteria are taken into account today:

• The sensitivity of oil to oxidation : A high level of unsaturated fatty acids in the composition of a vegetable oil tends to make it vulnerable to oxidation. Conversely, a high concentration of antioxidants has a protective effect. The sensitivity of a vegetable oil to oxidation can be directly correlated to its comedogenicity index, with fragile ingredients being more comedogenic.

• The texture and thickness of the oil : a vegetable oil that penetrates quickly and easily into the epidermis generally has a low comedogenicity index. These oils, which have a strong affinity with the skin, are referred to as dry oils and are primarily composed of omega-3 and omega-6. The greasier oils, which are more comedogenic, tend to contain omega-9 instead.

• The oil extraction process : An oil derived from a cold-press extraction method is often less comedogenic than an oil extracted with a solvent. Indeed, unlike other extraction methods, cold-pressing requires neither chemical treatment nor exposure to high temperatures, which preserves the active ingredients in the oil and prevents their oxidation.

Key Takeaway : An oil with a rating of 0 or 1 is recommended for individuals with oily or blemished skin. For normal to combination skin, it is possible to use an oil with a rating between 0 and 3. Finally, dry skin types are free from restrictions and can utilise all types of vegetable oils.