Today we are going to talk about a skin problem that is becoming more and more common: seborrheic dermatitis.
As name suggests, this is a dermatitis problem caused by hypersecretion of sebum. In fact, not all people with this condition have oily skin. People with dry skin may also develop disease in areas rich in skin glands.
How to tell it apart from acne by symptoms
Everyone knows symptoms of acne. There are various stages of blockage/inflammation/cyst/nodule of hair follicle, but in general it is still a diffuse lesion. With seborrheic dermatitis, most areas of skin prone to disease are rich in sebaceous glands: around mouth, nose, auricle, superciliary arches, as well as scalp, armpits, groin, chest and back, etc.
Symptoms are mainly scaling and redness (often erythema in skin folds), yellowish-white scales fall off, sometimes scabs and itching symptoms appear. For most people, seborrheic dermatitis starts on scalp, and dandruff can also be thought of as mild seborrheic dermatitis.
Excessive sebum secretion is an important predisposing factor for seborrheic dermatitis, but there is no causal relationship between two. Studies have found that composition of sebum of patients with seborrheic dermatitis differs from composition of sebum of normal skin: content of triglycerides and cholesterol is higher, and content of free fatty acids and squalene is low.
An even more closely related factor is associated with a lipophilic fungus: Malassezia. Yes, it is microbe that causes dandruff. How volitional is it? You can consult with friends who have beriberi (not beriberi, simple beriberi is also caused by fungi). Sometimes it goes away without treatment, and sometimes it recurs. Friends with seborrheic dermatitis, we must first work hard on psychological construct for a long-term fight.
Simply put, lipids secreted by skin glands are food for Malassezia bacteria, which can promote multiplication of Malassezia acquired by chance and/or genetically on skin. Irritants such as active oxygen penetrate our fragile skin barrier. , causing inflammation/flushing/scaling/itching that further damages barrier and recurs.
Anti-dandruff shampoo is not recommended
It goes without saying that anti-dandruff shampoo contains Malassezia-inhibiting ingredients that can help control seborrheic dermatitis in terms of effectiveness; however, in real conditions, there are also testimonials from patients with seborrheic dermatitis: using a shampoo (containing zinc pyrithione-ZPT) to wash your face and get rid of acne, why is this?
Firstly, ability of hair and scalp to be contaminated with oil is much stronger than that of skin of face, after washing it will be very dry and barrier will not be protected. At same time, to make hair less dry after washing, silicone oil is usually added to shampoos to smooth hair, which has a strong sealing effect (so-called blunt pox).
Can I use shampoo without silicone?
The answer is still no. Because silicone oil free shampoo needs to add other conditioners for smooth hair. For example, cationic conditioners are most common substitutes for silicone oil. Cationic conditioners irritate skin and can easily aggravate skin inflammation.