Oily Skin: Ingredients and Actives to Avoid in Your Skincare.

The term "comedogenic" originates from the word "comedones" and refers to the property of a cosmetic ingredient or a cosmetic product to block the sebaceous glands, which are responsible for the production of sebum. However, this blockage prevents the natural evacuation of sebum, which tends to cause various skin problems, such as dilated pores, open microcysts also known as blackheads or closed microcysts or whiteheads.

The concept of comedogenicity is measured on a scale from 0 to 5. A score of 0 indicates that no comedones have developed, meaning the pores are not blocked, and a score of 5 signifies a high probability that the cosmetic ingredient in question will cause comedones. The comedogenicity index of an ingredient is based, among other things, on its rate of penetration into the superficial layers of the skin and its vulnerability to oxidation. Any ingredient that has received a score of 2 or less is considered non-comedogenic. Here is a list of ingredients to avoid, incompatible with oily skin presenting occasional pimples.

• The animal waxes: Beeswax (cire d’abeille) and Lanolin (lanoline);

• Some mineral oils and waxes derived from hydrocarbons, often found in conventional foundations: Paraffinum Liquidum, Cera Microcristallina, Synthetic Wax, Petrolatum, Mineral Oil, Ceresin Wax, etc... ;

• Some vegetable oils and butters: Triticum Vulgare or Wheat Germ Oil, Argania Spinosa (Argan Oil), Persea Gratissima (Avocado Oil), Coco Nucifera or Coconut Butter, Cocoa Butter or Theobroma Cocoa (Cocoa Butter), Butyspermum Parkii or Shea Butter, Rosa Canina or Rosehip Oil, Castor Oil, etc... ;

• The gums and resins : Carageenan (Carrageenan), Algin (Sodium Alginate), Xanthan, etc...

• Certain fatty esters : Particularly derivatives of stearic and oleic acids or even isopropyl myristate, the unsaponifiables, squalanes and squalenes, etc...

These types of ingredients are effective only in the short term for "drying out" oily skin but are counterproductive in the long term. Indeed, following the drying phase, the skin system re-establishes itself to initiate a reactive hyperseborrhoea. Thus, the sebaceous glands produce a larger amount of sebum. This accumulation of sebum also promotes the growth of bacteria responsible for the onset of acne. This is the rebound effect.

The most common drying or detergent ingredients to avoid if you have combination to oily skin are:

• alcohol derivatives (SD 40 alcohol, denatured alcohol, ethanol, and isopropyl alcohol);

• Some surfactants such as lauryl sulfate or sodium laureth sulfate.

These harsh ingredients, if used over a prolonged period, can disrupt the skin's barrier function, making it difficult to retain moisture and also causing inflammation and irritation. This can worsen the overall condition of your skin and lead to excessive dryness, which will subsequently be compensated for by an overproduction of sebum.

Physical exfoliants, also known as mechanical scrubs, require manual rubbing, which can irritate skin already inflamed by acne. Therefore, they should be avoided in the case of acne. Moreover, excessive mechanical exfoliation can damage the hydrolipidic film. Harsh scrubs make the skin more sensitive and drier. Overly dry skin compensates and produces more sebum, which increases the risk of acne outbreaks.

Avoid all scrubs based on grains, whether these are natural (derived, for example, from crushed fruit kernels) or synthetic (poly-ethylenes or -propylenes PEG/PPG: polyethylene glycol, polypropylene...).

Opt for chemical exfoliants that work by breaking the intercellular bonds on the skin's surface to stimulate cell renewal. The best exfoliating acids for acne-prone skin are beta-hydroxy acids (BHA), astheirsebum-regulating propertiestarget the formation of comedones and prevent the pore blockages that cause blackheads. In skincare, the main B.H.A. used issalicylic acid, a fat-soluble acid. This active ingredient, originally extracted from willow bark, has interesting properties for the care of oily skin prone to imperfections. Thanks to itsantiseptic action, it prevents the growth and proliferation of fungi, viruses, and bacteria, such asCutibacterium acnes, a microorganism responsible for the inflammatory reactions ofacne.