Every year, usually somewhere between March and May in South Africa, a wave of patients walks into the clinic holding a photo of their shower drain. The shedding feels sudden and alarming. What most of them do not realise is that it was set in motion months earlier, during summer. That timing gap is exactly why seasonal shedding is far easier to prevent than to reverse.
Hair does not grow continuously. Each follicle cycles through a growing phase, a brief transition, and a resting phase called telogen, after which the hair releases and a new one starts pushing through. On a normal day you shed somewhere in the region of 50 to 100 hairs, and you never notice because the follicles are all on different schedules.
Seasonal shedding happens when an unusually large group of follicles enters that resting phase at roughly the same time. They sit there quietly for two to three months, then let go together. That is the shower drain moment. The medical term for it is telogen effluvium, and the seasonal version is the mildest, most predictable form of it.
Research has tracked this pattern fairly consistently. A study following nearly 3,000 people over two consecutive years found telogen rates climbing through late summer and peaking in early autumn, with the lowest shedding in the depths of winter. Those studies were run in the northern hemisphere, so the calendar flips for us. Our late summer is January and February, which means the shed itself tends to land somewhere in autumn, from about March through May.
Two things happen over a Johannesburg summer, and they work in different ways.
The first is the follicle-level trigger. UV exposure appears to push a higher-than-usual percentage of follicles into the resting phase. This is the delayed mechanism, the one that produces shedding months later rather than at the time.
The second is straightforward physical damage. Over a summer, hair fibre takes on sun, chlorine, salt water, heat styling, and more frequent washing than usual. That weakens the shaft itself, so hair breaks more easily. Breakage is not the same thing as shedding, but it lands on the bathroom floor looking identical, and it makes an ordinary seasonal shed look much worse than it is.
For anyone already dealing with underlying thinning, whether that is pattern hair loss, a thyroid issue, or low iron, the seasonal wave stacks on top of it. This is where an already-fragile situation starts looking dramatic.
Here is the awkward part. By the time you notice the shedding, the follicles involved have already finished their resting phase. The decision was made in January. Nothing you apply in April will pull those hairs back.
What treatment can do at that stage is support the next cycle, protect the follicles that have not shed yet, and rule out whether something other than the season is driving it. That is worth doing, but it is recovery, not prevention, and it takes months to show.
Preventing it works differently. If you protect the hair and scalp through summer, fewer follicles get pushed into telogen in the first place, and the fibre that does stay on your head is stronger. The shed still happens, because it is a normal biological rhythm, but it stays in the range where you never really notice it.
None of this is complicated, and most of it costs nothing.
Cover your scalp in direct sun. A hat over the crown and parting does more for seasonal shedding than any supplement, particularly if your hair is already thinning there and the scalp is exposed.
Rinse after swimming, every time. Chlorine and salt left sitting in the hair over an afternoon do real damage to the cuticle.
Back off the heat where you can. Summer already stresses the fibre, so daily straightening or blow-drying on high compounds it.
Get bloodwork done if you have any reason to suspect a deficiency. Low ferritin and thyroid issues both amplify seasonal shedding significantly, and both are easily checked. HDA Clinic works with various accredited pathology laboratory, when bloodwork is needed to confirm what is actually going on.
If you already know you shed heavily each autumn, treat the scalp before the season, not after. Non-surgical treatments such as PRP, mesotherapy and carboxy therapy work by improving follicle health and blood supply to the scalp, which is far more useful going into the trigger period than chasing the aftermath. A summer course, timed ahead of the shed, is one of the more sensible uses of these treatments.
Seasonal shedding has a shape to it. It arrives, it peaks over a few weeks, and it settles. Hair density returns to roughly where it was before.
Be more careful if the shedding continues past six months, if it comes with a visibly widening parting or receding hairline, if the scalp is itchy, flaky, sore, or inflamed, or if hair comes out in defined patches rather than diffusely. Those are different problems wearing the same costume, and waiting for the season to change will not fix any of them.
The reason a proper diagnosis matters is that hair loss rarely has one clean cause. Genetics, hormones, stress, nutrition, autoimmune activity, and scalp conditions all overlap, and seasonal shedding can be the thing that finally makes an underlying issue visible. That is not a bad outcome. It is often the most useful early warning a patient gets.
Most people shed between 50 and 100 hairs a day as part of the normal hair cycle. During a seasonal shed this can rise noticeably for a few weeks before settling back down.
Seasonal shedding usually peaks in autumn, roughly March to May, because it is triggered by conditions during the previous late summer. The follicles rest for two to three months before releasing, which creates the delay.
It typically runs for six to eight weeks and resolves on its own as the hair cycle rebalances. Shedding that continues beyond six months is no longer seasonal and should be assessed properly.
On its own, no. The follicles are resting rather than dying, and hair regrows. It becomes a concern when it sits on top of an existing condition like pattern hair loss, where it can accelerate visible thinning.
Both experience it, but women often notice it more because of hair length and the visibility of shed hairs when brushing or washing. Women are also more likely to have overlapping causes such as low iron or thyroid changes.
Before the trigger period rather than after the shed. In South Africa that means treating through spring and early summer, so the follicles go into the high-UV months in better condition.
If you are reading this in the middle of winter, you are in the best possible position. The next seasonal trigger window has not started yet, which means there is time to check for underlying causes and strengthen the scalp before summer does its work.
At HDA Clinic in Fourways, every consultation starts with an actual diagnostic assessment: scalp camera analysis, a proper look at your hair loss pattern, and bloodwork if the picture suggests it. From there you get a treatment plan built around what is genuinely happening on your scalp, not a generic product recommendation.
Dean Alister is a certified pure trichologist, accredited through the World Trichology Academy Certification and the School of Trichology London, with over 20 years of diagnostic experience in hair loss and scalp conditions. If your shedding turns out to be purely seasonal, he will tell you that too
