Quick summary: Hair Loss Tests
- Excessive hair loss often results from internal imbalances and requires proper diagnostics.
- The key tests include blood count, ferritin, thyroid hormones, vitamin levels and a hormonal panel.
- Trichology tests such as trichoscopy and trichogram complement laboratory diagnostics by assessing scalp and follicle health.
- Early diagnosis significantly increases the chances of stopping hair loss and choosing effective treatment.
Hair loss affects both women and men, regardless of age. While losing 50–100 hairs a day is completely normal, excessive shedding, thinning or the appearance of bald patches may indicate underlying health issues that require proper diagnostics. This is why tests for hair loss are a key element in identifying the root causes and creating an effective treatment plan. Before you reach for supplements or expensive trichology treatments, it’s worth starting with the right medical tests.
Why Should You Do Tests When Your Hair Is Falling Out?
Hair is one of the first indicators of internal imbalances in the body. Excessive shedding or weakening of the hair may result from:
- hormonal disorders
- vitamin and mineral deficiencies
- chronic stress
- autoimmune diseases
- scalp inflammation
- thyroid dysfunction
- iron metabolism problems
- food intolerances or infections
Without proper testing, it is difficult to determine the real cause. Diagnostics is the foundation of effective hair loss treatment.

Basic Hair Loss Tests – Where to Start?
1. Complete Blood Count (CBC)
This is the first essential test. It helps detect:
- anemia
- inflammation
- nutritional deficiencies
Even mild anemia may weaken the hair follicles and lead to noticeable thinning.
2. Ferritin – The Most Important Hair Health Marker
Ferritin stores iron in the body. Low ferritin is one of the most common causes of hair loss, especially in women.
Important:
You can have normal hemoglobin levels and still suffer from low ferritin — and your hair will fall out.
For optimal hair health, ferritin levels typically should be around 40–70 ng/ml, not merely “within the lab range.”
3. Thyroid Tests: TSH, FT3, FT4
Both hypothyroidism and hyperthyroidism can cause:
- thinning
- brittleness
- dullness
- weakened hair follicles
If results are abnormal, a doctor may order additional tests such as anti-TPO and anti-TG to check for autoimmune causes like Hashimoto’s disease.
4. Vitamin and Mineral Levels
Hair is a metabolically active structure that requires many nutrients. The most important ones include:
- Vitamin D3 – regulates the growth phase of hair
- Vitamin B12 – essential for cell division
- Folic acid – low levels contribute to hair fragility
- Zinc – crucial for skin and follicle regeneration
- Magnesium – supports metabolic processes in the follicles
Testing vitamin D3 is particularly important, as deficiencies are extremely common.

Hormonal Tests for Hair Loss
These tests are especially recommended for women experiencing:
- diffuse hair thinning
- receding hairline
- cycle irregularities
- acne or oily scalp
5. Androgen Levels
These include:
- total testosterone
- free testosterone
- DHEA-S
- androstenedione
Elevated androgen levels may indicate androgenetic alopecia (AGA) — the most common form of hair loss in both women and men.
6. Prolactin (PRL)
High prolactin levels can cause:
- hair loss
- menstrual disorders
- increased physiological stress
If prolactin levels are elevated, the doctor may recommend a metoclopramide stimulation test to determine whether the issue is hormonal or stress-related.
Trichology Tests – Scalp and Follicle Diagnostics
In addition to blood tests, trichology diagnostics provide valuable information.
7. Trichoscopy
A non-invasive camera examination that evaluates:
- hair density
- follicle condition
- follicle miniaturization
- inflammation
- dandruff, seborrhea and other scalp issues
Trichoscopy often points directly to the next diagnostic steps.
8. Trichogram
This test involves plucking hairs from different areas of the scalp and analyzing them under a microscope. It helps assess:
- the number of hairs in different growth phases
- the health of the bulbs
- the rate of shedding
This test is especially useful for complex or advanced cases.

Additional Tests Worth Considering
Depending on your symptoms, a doctor may also recommend:
- food intolerance tests
- autoimmune panel (ANA)
- CRP and ESR for inflammation
- cortisol level for chronic stress evaluation
When Should You See a Doctor or Trichologist?
You should book a consultation if:
- your hair is falling out in handfuls
- bald patches or visible thinning appear
- the problem lasts longer than 3 months
- your scalp itches, burns or flakes
- hair loss is accompanied by other symptoms (fatigue, cycle issues, sudden weight changes)
The earlier you start diagnostics, the higher your chances of stopping the process.
Summary. Which Tests Should You Do for Hair Loss?
The most important tests include:
- CBC
- ferritin
- TSH, FT3, FT4
- vitamin D3, B12, zinc, magnesium
- androgen profile, prolactin
- trichoscopy and trichogram
Hair loss is not just a cosmetic issue — it is a signal that your body may be struggling with deeper imbalances. Proper diagnostics help identify the cause and choose an effective, personalised treatment plan.
You can read more about trichology tips HERE. If the problem concerns you, we invite you to CONTACT us. Visit us on Instagram and TikTok.
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