Seasonal hair loss is a natural and temporary phenomenon that affects both men and women, mainly in autumn and spring.
It corresponds to an acceleration of hair renewal called acute telogen effluvium: more hairs simultaneously enter the resting phase, then fall out over a period of 4 to 8 weeks.
Normally, we lose between 50 and 100 hairs a day. During a seasonal peak, this loss can double or even triple, which can be significant but is not necessarily cause for concern. Seasonal hair loss is reversible and does not cause permanent bald patches.
However, if hair loss persists for more than three months or is accompanied by noticeable thinning of the hair, it is probably no longer a simple seasonal phenomenon. A specialist consultation can then help distinguish between temporary hair loss and a hair problem requiring treatment.
Seasonal hair loss refers to a greater than normal amount of hair loss occurring during the transitions between seasons. This phenomenon is distinct from pathological alopecia: it is diffuse (affecting the entire scalp), temporary, and does not leave permanent thinning areas.
Each hair follows a three-phase life cycle : growth (anagen), transition (catagen), and shedding (telogen). Normally, about 10 to 15% of hairs are in the telogen phase at any given time. During seasonal changes, this proportion temporarily increases, resulting in more significant hair loss a few weeks later.
This mechanism is well documented by dermatological research. Indeed, seasonal hair loss can increase daily hair loss to up to 175 hairs, or even more in the most sensitive individuals.
Autumn is the season when hair loss is most visible. This peak results from several mechanisms that combine.
During the summer, prolonged exposure to the sun stimulates the production of hormones that accelerate hair growth. More follicles enter the anagen phase, which explains why hair often appears denser in summer.
The flip side of this stimulation occurs 2 to 3 months later: hair that has completed its accelerated growth cycle enters the telogen phase en masse, and then falls out. This is why peak hair loss generally occurs between September and November.
At the same time, the reduction in light levels in autumn alters the production of melatonin, a hormone involved in regulating biological rhythms, including those of hair follicles. This hormonal change contributes to the synchronisation of hair loss.
The sun, seawater, chlorine from swimming pools and heat weaken the hair fibre and upset the balance of the scalp during the summer months. These cumulative stresses do not show up immediately, but contribute to the hair loss observed in autumn.
The return to work, the change of pace and end-of-summer fatigue are well-identified aggravating factors. Chronic stress is a known trigger for telogen effluvium, and the back-to-school period accumulates several forms.
Spring marks the second period of seasonal hair loss, often less intense than in autumn but still very real. The mechanism is partly symmetrical: the lengthening days cause a drop in melatonin production, which again disrupts the hair cycle.
In addition to this, there are the deficiencies accumulated during the winter, particularly in vitamin D (linked to lack of sunlight) and iron. These nutritional deficiencies weaken the follicles and promote more pronounced hair loss as the body adapts to the new light cycle.
The normal duration of seasonal hair loss is between 4 and 8 weeks. The first signs of regrowth generally appear within 3 to 6 months, and the density gradually returns to normal.
This is an essential point to remember: seasonal hair loss is a self-limiting phenomenon. It stops on its own once the follicles have completed their renewal cycle.
However, certain signs should raise concern and warrant a consultation:
These signs may indicate chronic telogen effluvium, uncorrected nutritional deficiency, or the onset of androgenetic alopecia , each of which requires specific management.
Hair is particularly sensitive to nutritional intake. To support the hair cycle during periods of seasonal shedding, certain nutrients play an important role: iron (especially in women), biotin (vitamin B8), zinc, selenium, vitamin D, and omega-3 fatty acids.
Opt for a varied diet rich in protein (eggs, fish, legumes), green vegetables, and seeds. A course of dietary supplements containing biotin, zinc, and iron can be considered at the first signs of hair loss, particularly as autumn approaches, provided that a blood test is first performed to confirm the existence of a genuine deficiency.
A few simple steps can help limit damage during sensitive periods: use a gentle shampoo (without sulfates), avoid washing too frequently with very hot water, limit the use of hair dryers and straighteners, and favor gentle detangling with a wide-tooth comb.
A gentle scalp massage of 2 to 3 minutes per day can also stimulate microcirculation and improve root nutrition.
When seasonal hair loss is particularly pronounced or occurs alongside pre-existing hair fragility, injection treatments can help stimulate regrowth more quickly. PRP (platelet-rich plasma) injections deliver growth factors directly to the follicles to stimulate their activity.
Hair mesotherapy, on the other hand, allows micronutrients and antioxidants to be injected as close as possible to the scalp.
Exosomes , the latest advance in regenerative medicine, represent a promising complementary option for strengthening the quality of regrowth.
These treatments are not always necessary for typical seasonal hair loss, but represent an interesting option when hair loss is recurrent or when density is slow to return.
Seasonal hair loss does not require a consultation in most cases. However, certain signs warrant medical advice: hair loss lasting more than 3 months, a noticeable decrease in density, progressive thinning of the hair, or the appearance of sparse areas.
A hair diagnosis allows us to analyze the condition of the scalp, to evaluate the anagen/telogen ratio and to distinguish benign seasonal hair loss from a more structural problem such as early alopecia or iron deficiency.
At the Croix d'Or Hair Clinic, Dr. Raphaël Meyer conducts comprehensive assessments to make an accurate diagnosis and propose a personalized treatment plan.
Yes, both sexes are affected. Women often report more visible hair loss due to the length of their hair, but the biological mechanism is the same. Seasonal hormonal variations may, however, be slightly more marked in women.
They can help if a deficiency is identified (iron, zinc, biotin, vitamin D). However, without a proven deficiency, their effectiveness remains limited. A blood test can help target real needs before supplementing.
Seasonal hair loss does not cause baldness. On the other hand, it can make an androgenetic alopecia that is already underway but has been discreet until now more visible. If the density does not return to normal after a few months, it is worth consulting a doctor to check that there is no hereditary component.
It cannot be totally prevented, as it is part of natural hair renewal. However, we can reduce its intensity by adopting a diet rich in essential nutrients from the end of summer, using mesotherapy-type injections to protect it, sheltering our hair from the sun during the warmer months, and avoiding overly aggressive hair care products.
Seasonal hair loss is a normal, temporary, and reversible phenomenon. It occurs mainly in autumn and spring, lasts 4 to 8 weeks, and does not cause permanent hair loss.
If your hair loss continues for more than 3 months or you notice your hair thinning, it is advisable to consult a doctor to check that there is not a deeper problem.
Schedule an appointment with our team in Geneva for a personalized diagnosis.
Make an appointment today for personalized and high-quality aesthetic care. Our team of experts is here to offer you innovative treatments tailored to your needs.
Please select all the means by which you would like to receive information from the Clinique de la Croix d'Or:
You can unsubscribe at any time by clicking the link in the footer of our emails. For more information about our privacy practices, please review the privacy policy on our website.
We use Mailchimp as our marketing platform. By clicking below to subscribe, you acknowledge that your information will be transferred to Mailchimp for processing. Learn more about Mailchimp's privacy practices