Seasonal Hair Shedding: Why You Lose More Hair in Fall
Seasonal Hair Shedding:
Why You Lose More Hair in Fall
And How to Tell When It Isn't.
Every autumn the same call comes in: more hair in the drain, more on the brush, and the fear that something is wrong. Usually it is the season. Sometimes it isn't — and in September the two look identical. Here is how a trichologist tells them apart.
Seasonal hair shedding is real, and the shedding you notice in autumn began in summer — a hair pushed into its resting phase stays anchored for roughly three months before it releases. Normal daily shedding is 50 to 100 hairs, and after an excessive shed, fullness usually returns within six to nine months.[1] The strongest evidence comes from trichograms in 823 women studied over six years, which found resting-phase hairs peaked in summer.[2] The part that matters clinically: a seasonal shed and a shed that will not stop look the same in September. The difference is in how long it runs, whether a pattern is forming, and whether the scalp hurts.
- What seasonal hair shedding actually is
- What the research really shows — and what it doesn't
- Why it happens is still an open question
- How much hair shedding is normal
- The gap nobody mentions: textured hair
- What actually helps — modifiable contributors
- Gentle scalp care while a shed runs its course
- Five signs it isn't just the season
- Seasonal shedding compared with other hair loss
- What happens at a scalp evaluation
- The evidence behind this article, graded
- Frequently asked questions
What Seasonal Hair Shedding Actually Is
Every hair on your scalp moves through a cycle: a long growth phase, a brief transition, and a resting phase. At any moment most of your hair is growing and a minority is resting. When a hair finishes resting, it releases, and a new hair grows in behind it. That is shedding, and it happens every day of your life.
Seasonal shedding is what happens when an unusually large group of hairs enters the resting phase at roughly the same time. They do not fall out immediately. A resting hair stays anchored in the scalp for around three months before it releases. So a cluster of hairs that shifted into rest during June and July comes out in September and October, all together, which is why it feels sudden when nothing sudden has happened.
The autumn shed starts in summer. Articles that explain fall shedding by blaming cold air, dry weather or dropping temperatures have the sequence reversed — the follicles made their decision months earlier, while it was hot. This matters practically: if you are looking for the cause, look at June and July, not at October.
What the Research Really Shows — And What It Doesn't
This topic attracts a great deal of confident writing that the evidence does not support. Here is the actual literature, with the sample sizes named, because the sample sizes are the story.
The strongest study analyzed trichograms from 823 women over six years at a Swiss university clinic, after excluding anyone with a disease or medication known to cause hair loss. It found a genuine annual rhythm: the proportion of resting-phase hairs peaked in summer, with a smaller second peak in spring, and the lowest values in late winter.[2]
A second study collected trichograms from 2,857 people across two consecutive years and found an increased frequency of telogen effluvium between July and October. Its authors added a detail almost nobody quotes: the effect looked more like a summer phenomenon than an autumn one in regions above the Tropic of Cancer.[3] North Carolina sits well above that line.
After those two, the evidence thins quickly. One study followed 41 volunteers.[4] Another, cited constantly as proof of seasonal shedding, followed 14 men.[5]
You will see articles citing research that "hair loss peaks in August and September," with precise multipliers comparing seasons. Those come from two Google Trends analyses[6][7] — they counted how often people searched the phrase hair loss, not how much hair anyone lost. Both were published as short research letters without abstracts, and their full texts sit behind paywalls, so the specific figures circulating online cannot be checked against the source. They are worth knowing as evidence that worry peaks in late summer. We are not going to print numbers we cannot verify.
Why It Happens Is Still an Open Question
The usual explanation is that humans retain a faint version of the seasonal coat-shedding other mammals have, triggered by changing daylight. It is a reasonable theory. It is also mostly supported by research in animals — badgers, sheep and goats — rather than in people.
A second theory points to cumulative sun exposure over the summer, sometimes called actinic effluvium. There is real mechanistic support for it: laboratory work on scalp skin showed that solar ultraviolet radiation reaching the skin surface triggers hair follicle damage, dystrophy and oxidative DNA damage.[8] But that work was done on tissue outside the body, not on living people going about a summer.
A 2020 review of the telogen effluvium literature states the position plainly: the ultraviolet mechanism is not scientifically proven.[9]
I would rather tell you that than pretend otherwise. Clinically, the mechanism is not what matters. What matters is what the shedding does next.
How Much Hair Shedding Is Normal?
The American Academy of Dermatology puts normal daily shedding at 50 to 100 hairs.[1] You will see higher numbers repeated across the internet — 50 to 150, or 80 to 100 — but 50 to 100 is the figure a dermatology body stands behind, so it is the one we use.
Counting is not practical and I do not ask clients to do it. A more useful question is whether your scalp still looks like your scalp. Part your hair down the middle and look at the width of the part. Look at your hairline, your temples and your crown. A seasonal shed thins your hair diffusely and temporarily. It does not carve out a shape.
On duration: after an excessive shed, hair tends to regain its normal fullness within six to nine months.[1] If you see a shorter figure quoted elsewhere — six to eight weeks is a common one — it does not come from a clinical source.
The Gap Nobody Mentions: Textured Hair
This is the section I most want the women in my chair to read, and I have not found it anywhere else.
Look again at who was actually studied. The 823-woman study was conducted in Switzerland. The 2,857-subject study was European. The 41 volunteers were in China. The 14 were British men. There is no published study of seasonal hair shedding in Afro-textured hair. Not a small one. None.
The same gap runs through the bedside test. The hair pull test is the oldest and simplest tool in trichology: a gentle pull on a bundle of hairs, counting how many release. For decades the threshold for a positive result was "more than about ten percent," roughly six hairs out of sixty. In 2017 a team actually validated it against 181 people and found the average number of hairs released was 0.44 — and that the old threshold had been repeated for decades with no citation or proof of validation behind it. Their revised guidance: more than two hairs is abnormal.[10]
That validation study's participants were 77 percent Caucasian hair texture, and its authors listed, among the things the pull test lacks, "hair texture considerations."[10] They were straightforward about it. The problem is what happened afterward: the number travelled, and the limitation did not. So for a Black woman sitting in a chair in September, both the seasonal baseline she is being measured against and the test used to measure her were built on populations that did not include her.
There is a further reason this matters. Afro-textured hair tends toward lower hair density and a smaller proportion of hairs in the growth phase than European hair. When the underlying density is lower, the same number of shed hairs represents a larger share of what you had — so a shed that a study would call average can look and feel considerably worse.
None of this means seasonal shedding does not happen in textured hair. I see it every year. It means nobody has measured it, and you should be suspicious of anyone who quotes you a precise number as though they had. Where the clinical picture in textured hair has been documented is in the conditions that hide behind a shed — I have written those up separately in CCCA, traction alopecia and AKN in Black women, with case records and trichoscopy.
What Actually Helps — Modifiable Contributors
You cannot switch a seasonal shed off. The follicles committed months ago and that decision is made. What you can do is address the things stacking on top of it — because in practice, most heavy autumn shedding is a seasonal shed plus something else, and the something else is usually fixable.
Iron and Ferritin Status
A meta-analysis of 36 studies and 10,029 women found those with non-scarring hair loss had ferritin levels significantly lower than women without it, and 21% sat at or below the low threshold.[11] Ask your physician for a ferritin test. Do not self-prescribe iron — iron overload is a real harm.
Rapid Weight Loss & Low Protein
Losing twenty pounds or more is on the AAD's list of shedding triggers.[1] The follicle is one of the most metabolically active tissues in the body, and adequate protein, calories and trace elements matter to it.[12] A summer of restriction shows up as an autumn shed.
Cumulative Sun Exposure
Ultraviolet radiation at the skin surface damages hair follicles in laboratory conditions.[8] The practical response is physical: shade, a hat, covering the part line on long days outdoors. This is the one lever that acts on next September rather than this one.
Smoking
Tobacco use has been associated with adverse effects on hair as well as skin.[13] It is not a seasonal factor, but it is a standing one, and it is on the short list of things genuinely within your control.
Mechanical Load & Traction
Tight styles, heavy extensions and high heat add breakage and traction on top of a shed. This is the only item here that prevents permanent loss rather than temporary shedding — traction alopecia scars if it runs long enough.
Medications, Illness & Post-Viral Shedding
Surgery, high fever, recovery from illness and stopping birth control all appear on the AAD's trigger list,[1] and each acts two to three months before you see it. Never stop a prescribed medication on your own — raise the timing with the prescriber instead.
Gentle Scalp Care While a Shed Runs Its Course
What follows is ordinary cosmetic scalp care for a scalp that is shedding — not a treatment for shedding, and not a substitute for the evaluation described further down. Most seasonal shedding resolves without any product at all. The purpose here is to avoid adding breakage on top of a shed that is already happening.
Most seasonal shedding settles on its own, and gentle care does not speed that up — it prevents you from adding a second problem on top of the first. If shedding is not easing, or a pattern is forming, that is a reason to be evaluated rather than to buy more products.
Five Signs It Isn't Just the Season
This is the part I want you to keep.
1. It has been going longer than six months
A seasonal shed rides through autumn and settles. Heavy shedding that runs past six months is classified as chronic telogen effluvium, which has its own causes worth finding.[14]
2. Your part is widening, or your hairline is moving
Shedding thins everything a little. Loss creates a shape. If the change has a pattern to it, something is happening alongside the shed.
3. Your scalp hurts
Tenderness, burning, stinging or itching — trichodynia — can accompany ordinary shedding.[9] But burning and tenderness at the crown, particularly with a part that keeps widening, is the presentation I never wave off. Central centrifugal cicatricial alopecia is a scarring condition: the follicles it takes do not come back. Inflammatory symptoms can precede visible hair loss, and they should not be reflexively blamed on dandruff or on styling.[15] In one biopsy-confirmed early-stage case I documented, the overhead view showed nothing more than a slightly wide parting — the perifollicular inflammation and early fibrosis were only visible under trichoscopy. The full case record is in my guide to CCCA, traction alopecia and AKN.
4. The hair is going where the hair is pulled
Traction alopecia hides best in September, because when everything is shedding a little, thinning edges do not stand out. It is common: community studies in Cameroon and Sudan found traction alopecia in 34.5% of 223 women and 25.0% of 192 women respectively.[16][17] Those are African community samples rather than US rates, but the mechanism does not change with geography. Caught early it is reversible: a hairline I treated over six months is documented with before and after imaging.
5. There is a trigger you haven't accounted for
Childbirth — shedding typically begins about two months after and peaks around four.[1] Surgery, high fever, significant weight loss, a medication change, thyroid disease or low iron stores. Each acts two to three months before you notice it, which lands a great many of them squarely in September and makes them look exactly like the season.
Almost every article on seasonal shedding ends with "see a dermatologist to rule out pattern hair loss or alopecia areata." Those are worth ruling out. But they are not the urgent ones. The urgent one is the scarring alopecia hiding inside a seasonal shed, because a seasonal shed costs you a few nervous months and a scarring alopecia costs you follicles. That clock only runs one direction.
Seasonal Shedding Compared With Other Hair Loss
| Feature | Seasonal shed | Chronic telogen effluvium | Female pattern hair loss | CCCA (scarring) | Traction alopecia |
|---|---|---|---|---|---|
| Timing | Starts in summer, seen Aug–Oct, settles | Runs beyond six months | Gradual over years | Slowly progressive | Follows styling history |
| Pattern | Diffuse, no shape | Diffuse, no shape | Widening part, crown | Crown outward, centrifugal | Hairline, edges, where tension sits |
| Scalp symptoms | Usually none; sometimes tenderness | Sometimes trichodynia | Usually none | Burning, tingling, tenderness — may come first | Tenderness, sometimes breakage |
| Reversible? | Yes | Yes, once the cause is found | Manageable, not self-resolving | No — follicles are lost | Yes early; scars if prolonged |
| How urgent | Watchful waiting | Worth investigating | Worth addressing | Time-critical | Time-critical if long-standing |
What Happens at a Scalp Evaluation
A trichological evaluation is a cosmetic assessment of the scalp and hair, not a medical diagnosis. What it is genuinely good at is telling the difference between shedding that will pass and a picture that needs a physician.
- History first. What was happening two to three months ago matters more than what is happening today. Illness, surgery, dieting, a new medication, a birth.
- Looking at the scalp under magnification, at the part, the crown, the hairline and the edges — including whether follicular openings are still visible, which is the question that separates scarring from non-scarring loss.
- A gentle pull test, read against the current evidence-based threshold rather than the old unvalidated one, and interpreted with its limitations in mind.[10]
- A wash test where it is useful — performed after five days without shampooing, counting the hairs released.[9]
- Knowing when to refer. Bloodwork and a scalp biopsy belong to a physician. A good evaluation ends in a referral when a referral is what you need.
The Evidence Behind This Article, Graded
Well supported, in narrow populations
Two independent trichogram studies — 823 women over six years[2] and 2,857 subjects over two years[3] — agree that resting-phase hairs increase in summer and shedding rises from July through October. The limit: both were European, and the smaller supporting studies had 41 and 14 participants. The pattern is real; the precision claimed for it online is not.
Meta-analysis level, and still disputed
A systematic review and meta-analysis pooling 36 studies and 10,029 women found significantly lower ferritin in women with non-scarring hair loss.[11] A separate review of 2,851 women with telogen effluvium found low ferritin in 46.5% of them.[18] The limit, stated plainly: the meta-analysis opens by noting there is no clear-cut evidence of the association, and a controlled study found no relationship between ferritin above 10 and hair loss activity in women.[19] Common, associated, causally unsettled.
Mechanistic only
Ultraviolet radiation reaching the skin surface produced hair follicle cytotoxicity, dystrophy and oxidative DNA damage in scalp tissue studied in the laboratory.[8] The limit: that was tissue outside the body, and the 2020 telogen effluvium review states the ultraviolet mechanism is not scientifically proven.[9] Plausible, unconfirmed in living people.
What the literature does not show
No study has examined seasonal shedding in Afro-textured hair. No controlled trial of any Kapyderm product in seasonal shedding or telogen effluvium exists, and none is claimed. Kapyderm formulas are cosmetic scalp care. Nothing on this page should be read as evidence that a product shortens a seasonal shed — most seasonal shedding resolves on its own, which is precisely why claims to the contrary are difficult to justify.
Frequently Asked Questions
- American Academy of Dermatology. Do you have hair loss or hair shedding? Source of the 50–100 hairs per day figure, the trigger list, the postpartum timeline and the six-to-nine-month recovery window. aad.org
- Kunz M, Seifert B, Trüeb RM. Seasonality of hair shedding in healthy women complaining of hair loss. Dermatology. 2009;219(2):105–110. doi:10.1159/000216832. PMID 19407435. Retrospective study over six years; 823 women after exclusions; maximal telogen proportion in summer, smaller peak in spring, lowest in late winter. pubmed
- Piérard-Franchimont C, Piérard GE. L'effluvium télogène actinique: une facette de la chronobiologie humaine. Int J Cosmet Sci. 1999;21(1):15–21. Trichograms from 2,857 subjects over two consecutive years; increased telogen effluvium July–October; effect described as more summer than autumnal above the Tropic of Cancer.
- Liu C, Yang J, Qu L, et al. Changes in Chinese hair growth along a full year. Int J Cosmet Sci. 2014;36(6):531–536. 41 volunteers — a small study, named as such.
- Randall VA, Ebling FJG. Seasonal changes in human hair growth. Br J Dermatol. 1991;124(2):146–151. Fourteen men. Widely cited as proof of seasonal shedding; the sample size is rarely mentioned alongside it.
- Hsiang EY, Semenov YR, Aguh C, Kwatra SG. Seasonality of hair loss: a time series analysis of Google Trends data 2004–2016. Br J Dermatol. 2018;178(4):978–979. PMID 29048738. A search-volume analysis, published as a research letter without an abstract.
- Buontempo MG, Ingrassia JP, Shapiro J, Lo Sicco K. Seasonal trends in hair loss: a big data analysis of Google search patterns and their association with seasonal factors. J Eur Acad Dermatol Venereol. 2023;37(12):e1458–e1460. PMID 37471104. Also a research letter without an abstract; full text paywalled. Measures search interest, not shedding.
- Gherardini J, et al. Transepidermal UV radiation of scalp skin ex vivo induces hair follicle damage that is alleviated by the topical treatment with caffeine. Int J Cosmet Sci. 2019. Solar UVA and UVB at the skin surface triggered follicle cytotoxicity, dystrophy and oxidative DNA damage. Ex vivo tissue, not living subjects.
- Asghar F, Shamim N, Farooque U, Sheikh H, Aqeel R. Telogen Effluvium: A Review of the Literature. Cureus. 2020;12(5):e8320. doi:10.7759/cureus.8320. States the actinic effluvium mechanism is not scientifically proven; also the source for trichodynia and for the modified wash test performed after five days without shampooing. pubmed
- McDonald KA, Shelley AJ, Colantonio S, Beecker J. Hair pull test: evidence-based update and revision of guidelines. J Am Acad Dermatol. 2017;76(3):472–477. 181 participants analyzed; mean 0.44 hairs removed; the previous threshold had been propagated without citation or validation; sample was 77% Caucasian hair texture; authors note the test lacks hair texture considerations.
- Treister-Goltzman Y, Yarza S, Peleg R. Iron deficiency and nonscarring alopecia in women: systematic review and meta-analysis. Skin Appendage Disord. 2022;8(2):83–92. doi:10.1159/000519952. 36 studies, 10,029 participants; mean difference in ferritin −18.51 (95% CI −25.85 to −11.16, p<0.01); 21% (12–29) at or below the low threshold. The authors open by stating there is no clear-cut evidence of an association.
- Trüeb RM. Effect of ultraviolet radiation, smoking and nutrition on hair. Curr Probl Dermatol. 2015;47:107–120. doi:10.1159/000369411. PMID 26370649. Normal supply of proteins, calories, trace elements and vitamins is fundamental to a tissue with the hair follicle's biosynthetic activity. pubmed
- Trüeb RM. Association between smoking and hair loss: another opportunity for health education against smoking? Dermatology. 2003;206(3):189–191. PMID 12673073.
- Whiting DA. Chronic telogen effluvium: increased scalp hair shedding in middle-aged women. J Am Acad Dermatol. 1996;35(6):899–906. The reference point for shedding that persists beyond six months.
- Olsen EA, Callender V, McMichael A, et al. Medical and environmental risk factors for the development of central centrifugal cicatricial alopecia: a population study. J Am Acad Dermatol. 2011. PMID 21482861. 326 African American women; 28% graded 2 or higher on a standardized central scalp alopecia photographic scale, 59% of those at grade 3 or higher with clinical signs of scarring; significant associations with type 2 diabetes, bacterial scalp infection and traction hairstyles. Note: a separate 2011 study of 529 African American women reported a prevalence of 5.6% — the two disagree substantially, and better prevalence data is still needed. pubmed
- Kouotou EA, et al. Hair care and epidemiological-clinical profile of traction alopecia among women in hair salons in Yaoundé, Cameroon. 223 women, mean age 24.9; traction alopecia prevalence 34.5%.
- Prevalence and associated factors of traction alopecia in women in north Sudan: a community-based, cross-sectional study. 192 women; 48 (25.0%) with traction alopecia; median age 42.
- Karakoyun Ö, Ayhan E, Yıldız İ. Retrospective review of 2851 female patients with telogen effluvium: a single-center experience. J Cosmet Dermatol. 2025;24:e70037. doi:10.1111/jocd.70037. PMID 39950230. Ferritin low in 1,123 of 2,413 tested (46.5%); iron deficiency in 685 (29.5%).
- Bregy A, Trüeb RM. No association between serum ferritin levels >10 µg/l and hair loss activity in women. Dermatology. 2008;217(1):1–6. The counterweight to the ferritin literature above, and the reason this article does not present iron as a settled cause.
19 sources: 1 systematic review and meta-analysis, 15 peer-reviewed journal articles, 2 search-interest research letters cited without their figures because those figures cannot be verified to source, and 1 clinical reference body. Sample sizes are named throughout rather than omitted, and studies with 14 and 41 participants are identified as such. No controlled trial of any Kapyderm product in seasonal shedding or telogen effluvium exists. No published study has examined seasonal hair shedding in Afro-textured hair. Last reviewed September 2026.
Most Autumn Shedding Passes.
The Rest Is Worth Looking At.
If your shedding has run past six months, your part is widening, or your scalp burns or feels tender, that is worth an evaluation rather than another product. Our specialists assess the scalp under magnification and refer to a physician when that is what the picture calls for.
