The Science of Cleansers

Cleansers primarily work through surfactants, which are molecules that bind to oily soils on the skin and help wash them away with water. There are different types of cleansers, including micellar waters and surfactant-based cleansers like soaps or synthetic detergents. Micellar waters have gained popularity, especially for makeup removal, often used as a first step in double cleansing. However, because micellar waters are typically no-rinse products, there’s a risk of leaving residues on the skin, which may irritate sensitive skin, especially if the products contain active ingredients. For this reason, it’s important that micellar waters be followed by rinsing and gentle cleansing to ensure the skin barrier is protected.

Surfactant choice is crucial for sensitive skin. Traditional soaps had a high alkaline pH that could disrupt the skin’s barrier by swelling the outer layer and making it more porous. Modern synthetic surfactants have a pH closer to the skin’s natural acidity, around 5 or 6, which helps maintain the acid mantle and reduces irritation. There is also a misconception that foaming is necessary for effective cleansing. While foaming agents produce satisfying bubbles that many consumers associate with cleanliness, research shows foam is not essential for cleansing to occur. Nonetheless, many patients prefer foaming cleansers because of the sensory experience, which can make adherence to a routine easier.

Patient preference plays an important role in cleanser selection. Many people expect a foaming sensation and even tingling, associating these sensations with a clean face. Despite the availability of milder surfactants that do not require pH-balancing toners, some patients remain attached to these sensations, which can pose challenges in clinical advice. The goal is to find a balance between effective cleansing and preserving the skin barrier, while also considering the patient’s experience and comfort with their routine.