Spring & Fall Lash Shed: Fact or Fiction?

Every spring and fall, lash artists hear some version of the same thing:

“I swear I'm losing more lashes than usual.”

And if you've worn extensions for several years, you may feel like you can almost predict it. Your retention is normally great, then suddenly you come in for a fill and there seem to be more missing lashes, more new little lashes growing in, or more extensions shedding between appointments.

It raises an interesting question:

Do humans actually have a seasonal shed like our pets do—or is “fall lash shed” just something the lash industry has repeated for years?

The answer is a little more interesting than a simple yes or no.

The short answer: there's evidence for seasonal HUMAN hair shedding—but eyelash-specific evidence is limited

Humans absolutely have a hair-growth cycle. And unlike many animals, our follicles aren't synchronized into one giant seasonal molt. Different human hair follicles are in different stages of their cycles at the same time.

But researchers have found seasonal patterns in human scalp-hair growth and shedding.

That's an important distinction.

There is good scientific evidence that human scalp hair can show seasonal variation. There is not equally strong research demonstrating that eyelashes undergo a predictable major spring-and-fall shed.

So when your lash artist says, “It's lash-shedding season,” she may be noticing something real—but science hasn't established that eyelashes reliably follow the same seasonal pattern.

What does the research actually show?

One of the larger studies examined 823 women over six years. Researchers at the University Hospital of Zürich analyzed their hair cycles and found a significant annual pattern.

The largest proportion of hairs in the resting—or telogen—phase occurred during summer. Researchers also observed what appeared to be a smaller secondary peak in spring.

An earlier study followed healthy men for 18 months and found something similar. The percentage of actively growing scalp hairs was highest around March and gradually declined, while actual shedding peaked around August and September. At that peak, average hair loss was more than twice what researchers observed during the preceding winter.

Another study examining the periodicity of human hair growth found the highest proportion of telogen hairs near the end of summer and beginning of autumn, although the pattern wasn't identical in every participant.

A study involving 2,857 people complaining of increased hair loss similarly found increased telogen shedding between July and October. The researchers suggested that what people think of as “autumn shedding” may actually originate from changes occurring during summer.

So seasonal hair shedding in humans isn't fiction.

But here's where we need to be careful.

Scalp hair isn't the same as eyelashes

This is the part that's often missing from social-media posts about “lash shedding season.”

Eyelashes have their own growth cycle, and it's quite different from scalp hair.

Medical reviews describe three major eyelash phases:

Anagen — growth: roughly 4–10 weeks.

Catagen — transition: approximately 15 days.

Telogen — rest: reported around 4–9 months in some medical references, after which the lash sheds and another growth cycle begins.

The complete eyelash cycle has been estimated at roughly 4–11 months, although studies and reviews report variation between individuals and even between follicles on the same person.

And here's something especially important for extension wearers:

Your lashes don't all enter those phases together.

Human follicles generally cycle asynchronously. While one natural lash is actively growing, another may be resting and another may be ready to shed.

That's why losing natural lashes throughout the year is normal.

So do eyelashes really shed more every spring and fall?

This is where I'm going to disagree slightly with the popular lash-industry explanation.

You'll frequently see statements online like:

“Humans shed their eyelashes twice a year, just like animals shed their coats.”

That's too strong.

The medical literature I found supports seasonal changes in human scalp-hair cycling, particularly increased shedding around late summer/early autumn, with some research finding a smaller spring peak.

However, I could not find comparable controlled human research demonstrating a universal twice-yearly spring-and-fall eyelash shed.

So our verdict would be:

Seasonal hair shedding: FACT.

Everyone having a major spring-and-fall eyelash shed: NOT PROVEN.

And that's actually more interesting than simply repeating the myth.

But why do lash artists swear they see it?

Because salon experience can still reveal patterns worth noticing.

When you work on hundreds or thousands of lash lines over many years, you get very familiar with what a client's normal retention and growth look like.

A longtime client may suddenly come in with more new growth than usual.

Another may have considerably fewer extensions remaining despite doing nothing differently.

Someone who routinely has excellent retention may suddenly notice more extended natural lashes shedding.

And then, several weeks later, everything appears normal again.

Those observations are legitimate. They simply aren't the same thing as a controlled scientific study proving that season caused the change.

Many things can influence hair shedding and growth, and timing alone doesn't prove the calendar is responsible.

What does this mean when you're wearing extensions?

This is where extensions make natural shedding much more noticeable.

A tiny natural eyelash falling out by itself isn't particularly dramatic. You may never even notice it.

Put an extension on that lash, however, and suddenly the shed lash is longer, darker and much easier to see.

Finding an extension with a natural lash attached doesn't automatically mean the extension ripped your lash out.

That natural lash may simply have reached the shedding stage of its cycle.

Hair researchers increasingly describe active shedding as its own process, called exogen, when the old hair fiber is released from the follicle.

Meanwhile, other follicles are producing new lashes.

And that's exactly why we do fills

A lash fill isn't simply putting extensions back into empty spaces.

Your natural lash line is constantly changing.

When you return to Lash Out, we may see extensions that are still appropriately positioned and don't need to be touched.

We'll see others that have moved farther away from the lash line because the natural lash underneath has continued growing.

Those grown-out extensions can be removed and replaced.

And we'll see new natural lashes that weren't ready for an extension at your previous appointment but have since grown enough for your stylist to evaluate.

Your fill is essentially maintenance of a constantly changing natural lash line.

A heavier shed doesn't automatically mean something went wrong

This is another important point for extension clients.

If you suddenly notice more shedding, it doesn't automatically mean:

“My adhesive isn't working.”

And it doesn't automatically mean:

“My extensions damaged my lashes.”

If the extension is still firmly attached to the natural lash that shed, the adhesive bond may actually have remained intact while the natural hair completed its cycle.

At the same time, unusually heavy or persistent eyelash loss shouldn't automatically be dismissed as “seasonal shedding,” either.

A clinical review of eyebrow and eyelash loss describes numerous potential causes of abnormal lash loss, including dermatologic, autoimmune, infectious, endocrine, nutritional and other conditions.

If someone develops persistent thinning, bald areas, inflammation, pain or another significant change, that's no longer something a lash artist should simply label “fall shed.” That's a conversation to have with an appropriate healthcare professional.

So…are we basically golden retrievers every spring and fall?

Not quite.

Your dog changing coats and a human eyelash completing its growth cycle aren't the same biological phenomenon.

But the idea behind “seasonal shedding” isn't completely made up, either.

Scientific studies have demonstrated seasonal patterns in human scalp-hair growth and shedding, with the strongest evidence pointing toward increased shedding around late summer and early autumn and some evidence for a smaller spring peak.

What science hasn't yet established is that everyone's eyelashes undergo a dramatic synchronized shed twice every year.

So when we notice what looks like a spring or fall lash shed at Lash Out, we can acknowledge what we're seeing without pretending the science says more than it actually does.

Your lashes are always growing.

They're always resting.

They're always shedding.

And they're always replacing themselves.

Sometimes you may simply notice that process a whole lot more than usual.

That's also why your lash fill may look a little different from one appointment to the next—we're not working with the same lash line every time.

We're working with the lashes you have growing today.

— Lash Out Extensions