Seasonal Hair Loss: Why September Is the Worst Month (And What Actually Works)

Every autumn, the same worried question floods search engines: "why is my hair suddenly falling out?" The answer is reassuring — and actionable.

The science of seasonal shedding

Hair grows in cycles: an active growth phase (anagen), a short transition, and a resting phase (telogen) at the end of which the hair falls. Studies tracking hair cycles across the year consistently find that a larger share of follicles enter the resting phase in summer — likely influenced by sun exposure and daylight patterns. Since telogen lasts two to three months, those hairs let go together in September and October. The result: shedding can visibly increase for several weeks, in both women and men.

The good news: it is temporary — and treatable

Seasonal shedding resolves on its own, but there are two reasons to act rather than wait. First, reducing the fall and stimulating regrowth shortens the visible thinning period. Second, autumn is when any underlying shedding (stress, postpartum, ageing) stacks on top of the seasonal wave — the earlier you support the scalp, the smaller the dip.

What actually works

Forget miracle promises: what works is consistent scalp care over a full hair cycle (3 months minimum). Caudalie's new VineOxyl™ range was clinically tested exactly on this: −53% hair loss after 3 months and +87% hair thickness in dermatologist-scored studies. The routine is two steps:

Caudalie

Anti-Hair Loss Serum — 3 to 4 pipettes on the scalp daily, no rinsing

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Caudalie

Density & Volume Shampoo — thickens the fibre at every wash

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Explore the full VineOxyl™ anti-hair loss collection — including the clinical results and the full FAQ.

Timing is everything

Starting in early September — before the shedding peak — means the actives are already working when the wave hits. Start now, hold for three months, and by the holidays your brush should be back to normal.

This article is for general information and does not replace medical advice. If hair loss is sudden, patchy or lasts beyond three months, talk to a dermatologist. Clinical figures provided by the manufacturer (Caudalie).