PCOS Hair Loss Blood Tests: What to Check (and Why “Everything Looks Normal” Isn’t Always the Full Story)

PCOS Hair Loss Blood Tests: The Most Important Tests to Stop Guessing and Start Supporting Regrowth

If you’re dealing with PCOS hair loss, chances are you’ve already tried something.

Maybe it’s been:

• expensive shampoos

• hair serums

• supplements like zinc or biotin

• cutting out gluten or dairy

• scrolling TikTok for “hair growth hacks”

And yet… your hair is still thinning. Your part line is widening. Your ponytail feels smaller.

This is usually the moment women get blood tests done, hoping for answers only to be told:

“Everything looks normal.”

But here’s the truth.

When it comes to PCOS hair loss, “normal” results don’t always mean optimal, and they don’t always explain what’s driving your symptoms.

That’s why targeted, strategic testing matters.

Because PCOS hair loss is rarely just one thing, it’s usually influenced by:

• androgen excess

• insulin resistance

• inflammation

• nutrient deficiencies

• thyroid dysfunction

• stress hormone patterns

Let’s go through the most important tests to check, what they mean, and why they matter.

Woman with beautiful hair

Why Testing Matters for PCOS Hair Loss

Hair is not essential for survival. So when the body is stressed, inflamed, depleted or hormonally imbalanced, hair growth is often one of the first things to suffer.

Testing helps identify the root cause so you can:

• stop guessing supplements

• address deficiencies properly

• support hormone balance strategically

• improve insulin sensitivity

• reduce inflammation

• create the best environment for regrowth

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The 7 Most Important Blood Tests for PCOS Hair Loss

1) Iron Studies + Ferritin (This One Is Non-Negotiable)

Iron status is one of the biggest contributors to hair shedding and thinning.

Ask for:

• ferritin

• serum iron

• transferrin

• transferrin saturation

• total iron binding capacity (TIBC)

Why ferritin matters:Ferritin reflects stored iron. You can have “normal haemoglobin” and still have low ferritin, and low ferritin can contribute to hair loss and poor regrowth.

This is one of the most common things I see missed.

2) Thyroid Testing (TSH Isn’t Enough)

The thyroid plays a huge role in hair growth cycles.

Many women only get TSH tested, but with hair loss you want a fuller picture.

Start with:

• TSH

• free T4

• free T3

• 
  

If there are symptoms like fatigue, cold intolerance, constipation, mood changes or unexplained weight changes, consider:

• thyroid antibodies (TPO-Ab and TgAb)

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Thyroid dysfunction is often overlooked in PCOS and it can contribute heavily to hair changes.

3) Androgen Panel (The Driver Behind PCOS Hair Thinning)

Since PCOS hair loss is often androgen-driven, this panel matters.

Ask for:

• total testosterone

• free testosterone

• SHBG (sex hormone binding globulin)

• DHEA-S

• (sometimes) androstenedione

Important note:Some women have “normal testosterone,” but low SHBG, which means more free androgen activity in the body.

This is why testing the full androgen picture matters, not just one number.

4) Fasting Insulin + Glucose (Plus HbA1c)

This is one of the biggest root causes behind androgen excess and hormonal disruption.

Ask for:

• fasting insulin

• fasting glucose

• HbA1c

  
  

Many women with PCOS are told “your glucose is normal” but insulin resistance can exist for years before glucose becomes abnormal.

And insulin resistance is one of the biggest drivers of:

• androgen excess

• inflammation

• weight struggles

• and hair loss

5) Vitamin D

Vitamin D plays a role in immune function, inflammation regulation, and hair follicle cycling.

Ask for:

• 25-OH Vitamin D

• 
  

Low vitamin D is extremely common, especially in women experiencing chronic inflammation, fatigue, hormonal issues and autoimmune thyroid tendencies.

6) Zinc (and Copper Balance When Needed)

Zinc is essential for:

• hair follicle function

• hormone metabolism

• immune regulation

• skin and scalp health

Ask for:

• plasma zinc (or serum zinc)

Important: Zinc supplementation without guidance can sometimes worsen mineral balance, especially if copper is already low.

This is why testing matters before supplementing.

7) Inflammation Markers (If Symptoms Suggest It)

Chronic inflammation contributes to scalp sensitivity, insulin resistance and hormone imbalance.

Consider:

• hs-CRP

• ESR

This can help identify whether your body is in a chronic inflammatory pattern, which may be affecting hair regrowth.

Additional Tests That Can Be Helpful (Case Dependent)

Depending on symptoms, history and cycle patterns, it may also be worth checking:

• B12 and folate

• full blood count (FBC)

• liver function (important for hormone clearance)

• prolactin

• progesterone (to confirm ovulation)

Not everyone needs every test — the goal is targeted testing based on symptoms, not a scatter-gun approach.

Why “Everything Looks Normal” Can Still Mean You’re Struggling

This is a big one.

Pathology reference ranges are often designed to detect disease, not to reflect optimal health.

So you might be told:

• “your iron is in range”

• “your thyroid is fine”

• “your testosterone is normal”

But you’re still losing hair.

That doesn’t mean nothing is wrong. It usually means the results need to be interpreted in the context of:

• symptoms

• cycle function

• metabolic health

• inflammation patterns

• nutrient depletion

• hormone ratios (not just individual numbers)

This is where working with someone who understands PCOS becomes a game-changer.

What to Do After You Get Your Results

Testing is only step one.

The goal is to create a targeted plan that supports:

• lowering androgens safely

• improving insulin sensitivity

• replenishing deficiencies

• reducing inflammation

• supporting ovulation and hormonal rhythm

• improving scalp and follicle health long-term

Hair regrowth takes time, but when the driver is supported properly, results become possible.

Final Thoughts

PCOS hair loss is not something you have to just accept.

There are reasons it happens, and there are clear steps you can take to support change — but the process starts with testing the right things.

If you’re ready to stop guessing, targeted pathology is one of the best places to start.

If you’re dealing with PCOS hair loss and you want clarity on what PCOS hair loss blood tests to order (and what your results actually mean), I can help.

Book a FREE Naturopathic PCOS Assessment Call and we’ll map out what’s driving your symptoms, what testing should be prioritised, and the next steps to support androgen balance, reduce inflammation and improve hair regrowth.