Oily or combination skin: how to tell the difference
The distinction sounds theoretical, and it is not: it is what decides the soap. Try the simplest test there is. Wash your face in the morning with plain water, put nothing on, and look in a mirror four hours later.
If the shine is everywhere, forehead, nose, cheeks and chin, your skin is oily. If it gathers on the T zone, forehead and nose, while the cheeks stay matte or feel slightly tight, your skin is combination. That is the most common case, and also the one handled worst, because people apply a product designed for the oiliest area to the whole face.
Two extra signs. Visible pores on the nose and around the nostrils point to oily skin. Skin that shines in the evening but feels tight after a shower is almost always combination skin that has been stripped.
Why your current soap may be keeping the shine going
This is the most counter intuitive mechanism in caring for oily skin, and the one people write to me about most. You use a product that promises « clear » skin, the immediate feeling is excellent, the skin almost squeaks under your fingers. And two hours later it shines more than before.
That is not your imagination. Skin is covered by a hydrolipidic film that protects it. A cleanser that is too harsh, typically sulfate based, removes that film along with the dirt. The skin is left bare, and it reacts the only way it knows: it produces more sebum to rebuild its barrier. That is the rebound effect. The more you strip, the more it oils up.
A cold process soap works differently. The glycerine produced by the reaction stays in the bar instead of being taken out, and superfatting deliberately leaves a share of untransformed oils behind. The result: the soap cleans without leaving the skin bare, so it does not trigger the overproduction. I explain it in detail in my article on cold process saponification.
What to read on the label
Four points are enough, and you can check them in ten seconds on any product.
- No SODIUM LAURYL SULFATE or SODIUM LAURETH SULFATE at the top of the INCI list. Those are the surfactants that trigger the rebound effect.
- Names ending in SODIUM …ATE : SODIUM OLIVATE for olive oil, SODIUM COCOATE for coconut. That is the signature of real saponification, not of a reperfumed industrial base.
- The word superfatted. On oily skin it does not weigh anything down: it prevents stripping.
- An absorbing active : clay or activated charcoal, depending on your skin type. That is what captures the excess sebum.
One last, quieter clue. If glycerine appears on the list of an industrial soap, it is often because it was added back after being removed during manufacturing. In a cold process soap it does not appear, because it was never taken out.
Clay or activated charcoal: which one for which skin
Both absorb, but not with the same intensity, and that is where the choice between oily and combination skin is decided.
