Hair Shedding vs Breakage: The Pull Test and the Bulb
Shed hairs are full-length with a small whitish bulb at the root, and losing 50 to 100 a day is normal. Broken hairs are short pieces with no bulb, and they mean the shaft is damaged, not that the follicle is shedding. The pull test tells you whether the shedding is active.
The drain is full of hair, and the panic is the same whether it is shedding or breakage. The two look identical in the shower and mean opposite things, and treating one like the other wastes months. Shedding is a follicle problem. Breakage is a shaft problem. The hair in your hand tells you which one it is, if you look at the end.
A shed hair is a full-length hair with a small whitish thickening at the root end, the bulb, which is the telogen hair leaving the follicle the normal way. A broken hair is a short piece with no bulb, because it snapped somewhere along the shaft. Length and the bulb are the whole diagnosis.
The bulb test
Pick up a few hairs from the brush or the drain and look at the ends. Full-length hairs with a bulb are shed hairs, and they are normal: the American Academy of Dermatology puts normal shedding at 50 to 100 hairs a day, because about 10 to 15 percent of scalp hairs sit in the resting telogen phase at any moment, and those are the ones you find on the pillow, in the drain, or on the brush.
Short pieces with no bulb, especially pieces an inch or two long, are breakage. The shaft snapped, and the cause is damage: heat, bleach, tight styles, rough brushing, or protein overload. Breakage does not mean the follicle is failing. It means the hair that already grew is being destroyed, and the fix is in how you treat it, not in a supplement.
The pull test
The pull test is the standard clinical screen for active shedding. Grab a small bunch, around 40 to 60 strands, between thumb and forefinger and pull firmly from root to tip. Six or more hairs coming free counts as positive for active shedding, which points toward telogen effluvium or another live process. Fewer than six is normal.
Do it on three days, not one, because shedding varies day to day. And do it on unwashed hair, because washing loosens hairs that were going to shed anyway and inflates the count. A positive pull test on three separate days is worth a dermatologist visit. A positive test once, after a wash, is usually noise.
What telogen effluvium actually is
Telogen effluvium is the shedding pattern where a shock to the body pushes a large share of follicles into the resting phase at once, and two to three months later they all shed together. The triggers are a high fever, surgery, childbirth, a crash diet, major stress, or stopping the contraceptive pill. The shedding is diffuse, all over the scalp, and it usually settles within three to six months once the trigger is gone.
The timeline is the diagnostic clue. Shedding that starts three to four months after a clear trigger is almost always telogen effluvium, and the outlook is good. Shedding with no trigger, or shedding that goes on past six months, needs labs: the American Academy of Dermatology recommends checking for thyroid disease, iron deficiency, and nutritional deficiencies as first steps in chronic cases.
Related reading
Readers working through “Hair Shedding vs Breakage: The Pull Test and the Bulb” often find these earlier guides useful as well: Hard Water and Hair: Chelating Shampoos, Noted, Ponytail Headaches and Traction: Notes on Tension, and Scalp Sunburn: The Parting Burn and What Changes Next Time.
Frequently asked questions
How do I tell shedding from breakage?
Look at the hair. Shed hairs are full-length with a small whitish bulb at the root. Broken hairs are short pieces with no bulb. Shedding is a follicle problem, breakage is a shaft problem, and the fix is different for each.
How much hair shedding is normal per day?
Fifty to 100 hairs a day, per the American Academy of Dermatology. About 10 to 15 percent of scalp hairs sit in the resting telogen phase at any moment, so that many coming out daily is normal turnover, not hair loss.
What is the hair pull test?
Grab 40 to 60 strands between thumb and forefinger and pull firmly from root to tip. Six or more hairs coming free counts as positive for active shedding. Do it on three separate days on unwashed hair, because washing inflates the count.
What is telogen effluvium?
Temporary diffuse shedding set off by a physical or emotional stressor two to three months earlier, like illness, surgery, childbirth, or a crash diet. A large share of follicles enters the resting phase at once, and they shed together. It usually settles within three to six months once the trigger is gone.