Syndets: the most respectful facial cleansing

What are syndets?

They are mild synthetic detergents, created specifically for the skin. They are not made with the classic saponification of fats and oils like traditional soaps, but with synthetic surfactants that respect the natural balance of the facial skin. That's why they are called "syndet": synthetic detergent.

How they work

Their molecules have a head that attracts water and a tail that traps grease, sebum, and impurities. When rinsed, they carry everything away without stripping the skin's good lipids or breaking its protective barrier. The result: clean, fresh face without a greasy film or tightness.

pH: the key that makes the difference

Skin has a natural pH between 4.5 and 6, which is slightly acidic. Syndets maintain it exactly there, usually between 4.5 and 6.5. This way, they respect the acid mantle, the microbiota, and the skin barrier. They cleanse deeply without altering anything. That's why they don't dry out or irritate, even on sensitive, atopic, or reactive skin.

Traditional soaps, on the other hand, have an alkaline pH that can reach 9-10. They clean, yes, but at the cost of temporarily altering the skin's balance. For the body, this may be acceptable. For the face, where the skin is thinner and more delicate, syndets are clearly the smarter choice.

Properties and benefits

• Cleanse without disrupting the hydrolipidic film or the skin barrier.
• Respect the skin microbiota thanks to their adjusted pH.
• Do not dry out or irritate, even with daily use.
• Ideal for dry, combination, oily, acne-prone skin, or after treatments like peels, laser, or retinol.
• Suitable for the whole family: children, pregnant women, and mature skin.
• A well-formulated syndet can reduce the need for moisturizer after washing.

Curiosities and facts

Syndets were born in the 1940s-50s because classic soaps greatly irritated soldiers in World War II, whose skin was dry from the cold and hard water. From the war, at least, something good for the skin came out.

The first commercial syndet had the slogan "it's not soap," and it worked because people noticed the difference from the first use.

Syndets do not form the abundant lather of alkaline soaps. Their foam is finer and creamier, and that is precisely a sign that they respect the skin barrier. Fewer bubbles, more care.

They do not contain residual caustic soda like some homemade soaps. The entire process is controlled so that nothing irritating remains in the final product.

In modern hammams and spas, they are increasingly used because they cleanse deeply without leaving the skin feeling "naked" after washing. The ritual that truly cares.

Common surfactants in syndets: how they appear in the INCI

Surfactants are the heart of any syndet. These are the most common in quality formulas and how you will find them on the label:

• Sodium Cocoyl Isethionate: derived from coconut, one of the mildest and most used in solid syndets. Generates a creamy foam and leaves skin soft.
• Disodium Cocoyl Glutamate: plant-derived surfactant from coconut and glutamic acid, very well tolerated even on atopic skin.
• Cocamidopropyl Betaine: amphoteric derived from coconut, improves lather and softens the effect of other surfactants. Also found in mild shampoos. It has its own entry in Betaine.
• Lauryl Glucoside and Coco Glucoside: surfactants from the glucoside family, derived from sugar and vegetable oils. Very mild, biodegradable, and suitable for sensitive skin.
• Sodium Cocoyl Isethionate, Lauryl Glucoside, Disodium Cocoyl Glutamate or Cocamidopropyl Betaine in the INCI are signs that you are looking at a well-formulated cleanser.

Other active ingredients and products that may interest you from our “Learn more” archive

Coconut surfactants: to understand in detail how coconut-derived surfactants work.
Betaine: coconut betaine is one of the mildest and most common surfactants in quality syndets.
Clays: kaolin and illite, present in many syndets to enhance cleansing and absorb sebum.
Aleppo soap: to compare with traditional soap and understand why syndets are different.
Natural deodorants: same philosophy of skin respect, applied to another sensitive area of the body.