We tend to imagine hair loss as more hair in the shower, on the brush or on the pillow.
But a hair follicle can change long before dramatic shedding becomes apparent.
Sometimes the first sign is not more hair being lost, but less visible density: a widening part, a thinner ponytail, more visible scalp or increasingly fine hairs in an area that once appeared fuller.
This is not simply another way of describing the same problem.
Shedding, follicular miniaturisation and hair-shaft breakage are biologically different processes.
01 / THE HAIR WE LOSE TODAY MAY REFLECT AN EVENT FROM MONTHS AGO
The hair follicle follows a cycle.
During anagen it actively produces hair. This is followed by the short catagen phase of regression and then telogen, while the release of the old hair is often described separately as the exogen phase.
On a healthy scalp, follicles are not synchronised.
In telogen effluvium, a particular event can cause an unusually large number of follicles to transition towards telogen.
Febrile illness, childbirth, surgery, rapid weight loss, certain medications and nutritional disturbances may be among the triggers.
But visible shedding often appears only several months later.
The hair loss we see today may therefore be the biological echo of an event that has already passed.
02 / SHEDDING AND MINIATURISATION ARE NOT THE SAME THING
In androgenetic alopecia, one of the key processes is follicular miniaturisation.
A follicle that once produced a thick terminal hair progressively begins to produce a hair of smaller diameter and shorter length.
A person may therefore never experience a dramatic episode of shedding.
The number of hairs may not initially appear dramatically different, but their ability to cover the scalp is.
One hundred thick terminal hairs and one hundred highly miniaturised hairs are mathematically the same number.
Visually, they are not the same amount of hair.
That is why a widening part may sometimes tell us more than the number of hairs in the shower drain.
03 / TRICHOSCOPY REVEALS WHAT THE EYE MAY NOT YET SEE
Trichoscopy allows us to examine characteristics of the hair and follicular units that are difficult to assess with the naked eye.
In androgenetic alopecia, one characteristic finding is hair-shaft diameter diversity.
Within the same area, thicker terminal hairs coexist with increasingly fine miniaturised hairs.
An increased proportion of vellus hairs and other characteristic signs may also be visible.
This is why a dermatologist does not assess only how much hair is present.
We also assess what kind of hair individual follicles are producing.
04 / SOMETIMES THE FOLLICLE IS NOT THE PROBLEM
Hair can appear thinner because of breakage.
The visible hair shaft is a keratinised fibre that cannot biologically regenerate itself. Bleaching, chemical treatments, heat, UV exposure, friction and repeated mechanical stress can damage the cuticle and cortex.
As the surface becomes damaged, friction, tangling and susceptibility to breakage increase.
The result may be reduced volume, numerous short hairs and a thinner ponytail.
Visually, this can resemble hair loss.
Biologically, it is very different.
In alopecia, the follicle or the hair cycle is changing.
With breakage, the follicle may be producing normal hair, but the fibre is unable to retain its length.
05 / SOMETIMES THE SCALP PROVIDES THE MOST IMPORTANT CLUE
Itching, burning, pain, erythema, crusting or perifollicular scaling associated with hair loss deserve particular attention.
This is especially important in scarring alopecias.
In these conditions, inflammation may affect the region of the follicle containing an important population of epithelial stem cells. If the follicle is irreversibly destroyed and replaced by fibrosis, it can no longer produce a new hair.
This is fundamentally different from telogen effluvium, in which the follicle remains capable of entering an active growth cycle again.
In some scarring alopecias, early treatment is therefore not simply about achieving improvement sooner.
The aim is to prevent further irreversible follicular loss.
06 / FORGET THE OBSESSION WITH “100 HAIRS A DAY”
The number of hairs a person sees depends on washing and brushing frequency, hair length and the point at which an already released hair physically separates from the scalp.
Someone who washes their hair every day may see a small number of hairs each time.
Someone who washes every five days may see many at once.
That does not automatically mean that the second person is losing hair five times faster.
A change relative to your own normal pattern is more informative.
Is the part widening? Is volume decreasing? Is the frontal hairline changing? Are the hairs becoming finer? Is there more breakage?
Standardised photographs taken from the same angle and in similar lighting can be useful precisely because changes developing over months are difficult to notice from one day to the next.
07 / WHAT IS A DERMATOLOGIST TRYING TO DISTINGUISH?
When a patient says, “I’m losing my hair,” the diagnostic process is only beginning.
Was the change sudden or gradual? Diffuse or localised? Is the main problem shedding, miniaturisation or breakage? Is the scalp inflamed? Is there a family history? Was there an illness, childbirth, medication change, dietary change or significant weight loss several months earlier?
Clinical examination and trichoscopy then guide further investigation.
Laboratory testing should be selected according to the clinical findings and medical history.
There is no universal “hair loss panel” that every person requires.
Good diagnostics begin with one question:
What biological process are we trying to explain?
LOOK FOR CHANGE, NOT A NUMBER
Hair may become less dense because more follicles enter telogen.
A follicle may miniaturise.
The hair shaft may break.
And in certain diseases, the follicle itself may be progressively destroyed.
From the outside, all of these can end with the same sentence:
“I have less hair.”
Biologically, they are different stories.
The most important early sign is therefore not a particular number of hairs in the shower.
It is a change from what has been normal for your hair.