Thinning hair: what a trichology assessment looks at

Before you go: what to bring

• The dates: when the shedding or thinning began, and what happened in the months before, such as an illness or high fever, a birth, an operation, a new medicine, a strict diet or a stressful time.
• Recent blood test results, if you have them.
• A list of your medicines and supplements, biotin included: biotin can make some blood test results wrong.
• How you wear and treat your hair: tight styles, extensions, a tightly pinned scarf, bleaching, relaxers or high heat.

Step one: your story

Most of the diagnosis comes from the history. The doctor asks when the loss began and how, whether it is more hair in the brush or finer hair growing back, and what happened in the months before. Timing matters because shedding after a trigger usually starts a few months later, so a fever in spring can show in the shower in summer. Diet, health, medicines, family history and periods (in women) all count: pattern hair loss often runs in families, and acne, irregular periods or new hair growth can point to a hormone condition.

Step two: the pattern and the scalp under magnification

The doctor looks at where the hair is thinner: the temples or crown, a wider parting with the front hairline kept, round smooth patches, or the hairline where styles pull. A gentle pull on a small bunch of hairs shows how many come away. Then the scalp and hair are examined under magnification, called trichoscopy: it is non-invasive, helps tell the kinds of hair loss apart, and gives a record against which changes can be followed over time. A small skin sample is needed only in difficult cases.

Step three: blood tests, when they would help

Not everyone needs them. When your history or scalp suggests it, the doctor may suggest tests, for example for iron or thyroid function, since low iron and a thyroid problem can both cause shedding and can look much like pattern hair loss. If iron is low, putting it right is recommended; a thyroid problem needs its own treatment. Supplements make most sense once a test shows what, if anything, is missing: too much vitamin A or selenium can itself cause hair loss.

What the assessment tells apart

• Pattern hair loss: finer, shorter hairs at the temples or crown in men, or over the top with a wider parting in women; gradual, and tends to continue.
• Shedding (telogen effluvium): sudden, even shedding all over, a few months after a trigger; it usually settles as the body readjusts.
• Alopecia areata: round, smooth patches that appear quickly; hair often regrows, though new patches can follow.
• Traction: thinning where styles pull; early on, hair can recover once the pull stops.
• Breakage: hair snapping along its length after bleaching, relaxing or heat, not loss from the root.
• Scarring: smooth, shiny skin where the follicle openings have gone; uncommon, and the hair does not regrow.

When it is a dermatologist's case

See a doctor promptly if hair falls out suddenly or in patches, if a child is losing hair, or if the loss comes with tiredness, weight change or feeling unwell. A scalp that is painful, red or scaly, or smooth and shiny where hair has gone, can mean scarring hair loss, which a dermatologist should see quickly: hair lost to scarring does not regrow, so early diagnosis matters. A trichologist's title covers different training, and in many countries trichologists are not medically qualified; at CREAMÉ the assessment is with a doctor, Dr. Olga Seredina, and if it points to a dermatologist, we tell you.

What a first visit should not do

It should not sell you a course, shampoo or supplement before anyone has told you what kind of hair loss you have. No shampoo or serum corrects low iron, a thyroid problem, traction or a scalp infection, and for some causes, such as shedding after an illness or a birth, the honest answer may be no treatment at all. Where treatment does fit, expect months rather than weeks: for pattern hair loss, the usual treatments need at least six months before they can be judged.