Learn more about your hair and scalp.
Find out how to take better care of them.
Chat led by Doctor Philippe ASSOULY, Dermatologist specializing in the scalp, associate at Centre Sabouraud, Hôpital Saint Louis, Paris.
Chat transcription:
Question 1
Internet user: What is a hair? What is the scalp made of?
Doctor Philippe ASSOULY: Comprised of keratin, the hair is a skin appendix, like fingernails. It is found on the scalp. The scalp is what covers the human head. It could be called "the skin of the cranium". Diseases can affect the hair itself, but mostly the scalp.
Question 2
Internet user: I suffer from itching at the bottom of my neck whenever I dye my hair. What should I do?
Doctor Philippe ASSOULY: It may be eczema, a rash (allergy) or a simple irritation. If it is an allergy, a doctor will diagnose it and may order tests. If it is a simple irritation, you may just wish to switch your hair colour product or your shampoo.
Question 3
Internet user: When you suffer from scalp irritation and itching, how can you know if it is psoriasis or seborrhoeic dermatitis?
Doctor Philippe ASSOULY: Psoriasis is characterized by thick, scaly, clearly defined patches. Seborrhoeic dermatitis is more widespread and also often affects the face. A dermatologist is the best person to decide which of the two is present. However, a same person may suffer from both of these conditions at the same time.
Question 4
Internet user: Does chamomile really lighten the hair?
Doctor Philippe ASSOULY: That is an ancient notion that is not completely false. However, its effect remains limited.
Question 5
Internet user: Is washing your hair everyday necessary? For information, I have greasy hair and I have to wash my hair every day. What hair product do you recommend?
Doctor Philippe ASSOULY: Your hair needs to be washed when it is dirty. If daily shampoo is necessary, it is not a problem if the shampoo that is used is mild (for example, the shampoos in the Nodé range). If a woman has very greasy hair and is on birth control, it should be adapted.
Question 6
Internet user: I lost a lot of hair after my pregnancy. What do you recommend to revitalize my hair and especially my scalp?
Doctor Philippe ASSOULY: Losing hair a few weeks after giving birth is a common and normal phenomenon. During pregnancy, almost of all a woman's hair is in the growth phase (the anagen phase). After childbirth, this phenomenon stops and a higher percentage of the hair enters the shedding phase (called the telogen phase). This hair loss is in fact physiological. It can continue if there is an iron deficiency, so this may be something to watch for. While this phenomenon is particularly observed when you wash your hair, shampoos are not responsible and should be used as usual.
Question 7
Internet user: My hair alternates between greasy and dry. How can I make it normal?
Doctor Philippe ASSOULY: You should check to see if external factors may be causing these modifications: aggressive shampoos, extreme heat sources or blow-drying, occlusion (hat, cap, helmet, etc.).
Question 8
Internet user: How can I have shiny hair that is less brittle, especially during pre-menopause when I dye my hair every month? Do I need to take lots of food supplements?
Doctor Philippe ASSOULY: A balanced diet is more useful than food supplements. A hormonal treatment prescribed by a doctor can improve the hair's condition in the pre-menopause period. The dye that you use should be as mild as possible.
Question 9
Internet user: Can I highlight or dye my hair right after a period of intense hair loss (post-childbirth, season, stress, etc.)?
Doctor Philippe ASSOULY: Hair dyes, if they do not cause irritation, do not trigger hair loss. They are therefore not problematic in this case.
Question 10
Internet user: Why does hair colour change over time? What phenomenon is responsible for the onset of grey hair?
Doctor Philippe ASSOULY: When melanocyte (cells that determine skin and hair pigmentation) activity slows down, it causes grey hair to grow. This is a form of local cell ageing that depends on predispositions that are usually inherited.
Question 11
Internet user: Do you have tips to soothe the scalp? To keep from scratching the scalp when it itches?
Doctor Philippe ASSOULY: An itchy scalp is merely a symptom. If changing your shampoo does not help, a diagnosis needs to be made by a dermatologist.
Question 12
Internet user: Conditioners are highly recommended by brands. What do they really do? Are they necessary or purely commercial?
Doctor Philippe ASSOULY: A conditioner can be useful for dry and damaged hair. It may not be necessary if the responsible factors are eliminated (aggressive shampoos or brushing, etc.).
Question 13
Internet user: I have thin hair (like a lot of elderly people). Is it hereditary or is it caused by excessive dyes and perms?
Doctor Philippe ASSOULY: Androgenic alopecia (lack of hair) on the top of the scalp (vertex) can be related to hormonal factors and ageing. This phenomenon is indeed influenced by heredity - but not just that. Perms could promote increased hair loss if they are aggressive and repeated.
Question 14
Internet user: Can cold weather damage hair? If so, what should be done to protect it?
Doctor Philippe ASSOULY: Cold weather itself causes little damage to the hair. During this period, the shampoos you use should be particularly mild. Wearing protective clothing (winter hats, etc.) may promote the onset of itching and dandruff. You should therefore adapt your shampoo.
Question 15
Internet user: My hair is very curly and dry. Can you recommend a specific shampoo? If so, what would its benefits be?
Doctor Philippe ASSOULY: Shampoos (specific for dry hair) should not be applied frequently. You should avoid violent traumas (especially straightening). In your case, conditioners are generally useful.
Question 16
Internet user: Where should I go for a diagnosis of my scalp and hair?
Doctor Philippe ASSOULY: To a dermatologist.
Question 17
Internet user: How do anti-hair loss lotions prevent or curb hair loss?
Doctor Philippe ASSOULY: One single molecule has proven to be effective over time when applied locally in the case of chronic hair loss: minoxidil.
Question 18
Internet user: Do styling gels damage the hair and scalp?
Doctor Philippe ASSOULY: Not especially.
Question 19
Internet user: Do the hair and scalp need to be protected from the sun?
Doctor Philippe ASSOULY: The sun dries out and bleaches the hair. The hair protects the scalp from the sun. If the hair is sparse, the scalp will need to be protected, like the rest of the body, from possible sun damage.
Question 20
Internet user: Are anti-hair loss food supplements really active and do they limit hair loss?
Doctor Philippe ASSOULY: If the hair loss is short-term, it may be useful to take food supplements temporarily. However, a balanced diet is healthier and does not require supplements.
Question 21
Internet user: What are the best practices to prevent hair loss?
Doctor Philippe ASSOULY: If there are no medical causes behind the hair loss, the best strategy will be to limit local traumas. In the case of androgenic alopecia (constitutional hair loss in men or women), a treatment may be prescribed by a dermatologist.
This transcription does not necessarily represent all the discussions that occurred during the chat..