What Your Scalp Might Be Telling You About Your Health

Most people think of their scalp the way they think of the top of their head: something to shampoo, something to treat when it acts up, and otherwise something to ignore. But your scalp is skin, and like all skin, it can reflect what's happening inside your body.

This isn't about diagnosing conditions from symptoms. It's about understanding that certain scalp changes, especially sudden or persistent ones, are worth paying attention to rather than dismissing or masking with a new shampoo.

Here's what some of the most common scalp changes might be pointing to.

When Shedding Increases Suddenly

Some shedding is completely normal. The average person sheds between 50 and 100 hairs per day as part of the natural growth cycle. But when shedding increases noticeably and persists for several weeks, it's usually a signal worth taking seriously.

The most common systemic triggers for increased shedding include significant physical or emotional stress, hormonal shifts, nutritional deficiencies (particularly iron, ferritin, zinc, protein, vitamin D3, and certain B vitamins), thyroid dysfunction, and major illness or surgery. In each of these cases, the hair growth cycle is disrupted at the follicular level, pushing more hairs into the resting and shedding phase simultaneously.

This pattern, known as telogen effluvium, typically shows up around two to three months after the triggering event rather than immediately, which is why the connection can be easy to miss. We see it regularly at Cosh, and the first step is always the same: figure out what changed in the months before the shedding started.

GLP-1 Medications and Hair Shedding

One pattern we're seeing with increasing frequency is clients experiencing hair shedding while taking GLP-1 receptor agonist medications, the class of drugs widely used for weight management and blood sugar regulation.

The relationship between these medications and hair loss is an area of active and growing clinical investigation. Multiple studies that have monitored the effects of GLP-1s and real-world cohort analyses have now identified a meaningful association between GLP-1 receptor agonist use and increased rates of hair loss, including both telogen effluvium and androgenetic alopecia. What's less settled is the underlying mechanism. Rapid weight loss is one plausible contributor, since significant caloric restriction is a known trigger for telogen effluvium in its own right. But some researchers have also raised the possibility of a more direct pharmacological effect, noting that GLP-1 receptors have been identified in hair follicles in animal studies, though their precise role in the human hair growth cycle is not yet clearly defined. The current evidence does not allow us to definitively distinguish between these mechanisms, and the research is still developing.

If you're on a GLP-1 medication and noticing increased shedding, it's worth discussing with your prescribing physician. From a scalp perspective, maintaining a healthy scalp environment through consistent care is a sensible supportive measure while you work with your medical team on the broader picture.

We'd also encourage you to come in for a scalp analysis (Included with all treatments except Cleanse). While we don't treat the systemic cause, understanding what's happening at the scalp level and ruling out any contributing local factors is a useful part of the overall picture.

When Scalp Changes Feel Sudden or Unexplained

A scalp that suddenly becomes significantly oilier, significantly drier, more sensitive, or more inflamed than your established baseline, without an obvious change in products or environment, is worth noting.

Hormonal shifts are a common driver: puberty, pregnancy, postpartum recovery, perimenopause, and menopause all affect sebaceous gland activity and can shift your scalp's oil production, texture, and sensitivity. Thyroid changes are another frequent factor that can alter scalp and hair texture, sometimes before other symptoms appear.

We wrote in more detail about how stress in particular shows up on the scalp in an earlier post, if that's the angle you're most curious about.

None of this is meant to alarm. The scalp is responsive, and most changes have manageable causes. The point is that paying attention to those changes, rather than assuming they're cosmetic, tends to lead to faster answers.

What a Scalp Analysis Can and Can't Tell You

At Cosh, every treatment (except the Cleanse) begins with a trichoscope scalp analysis. We can visually assess sebum distribution, follicular density, signs of inflammation, scaling patterns, and the condition of the hair shaft. This gives us a clear picture of what's happening at the scalp level, and it's often the first time a client has seen their own scalp up close.

What we can't do is diagnose systemic conditions. If your scalp analysis reveals something that points toward a dermatological or medical concern, we'll tell you clearly and recommend you follow up with a dermatologist or your primary care physician.

That combination, professional scalp assessment plus appropriate medical follow-up when warranted, is the most useful approach we know.

Not sure if what you're experiencing is normal? Come in and let us take a look. We'll tell you what we see and what we'd recommend, including if that recommendation is to see someone else first.