So-called atopic skin combines several disadvantages. The first of these is an altered hydrolipidic barrier, which no longer fulfills its protective function correctly. Hence a hyper-reactivity of the skin to climatic conditions, to pollution and more particularly in the city, which often results in itching, redness, or tightness. Then, atopic skin will be extremely sensitive to allergens, which will sometimes lead to the appearance of atopic dermatitis, often in the form of eczema. Poor protection against contact allergens will maintain inflammatory reactions that will sensitize and weaken the skin a little more, which will make it even more reactive to the next allergen contact.