Blood tests can be useful when you are experiencing hair loss because thinning or shedding is sometimes linked to something happening elsewhere in the body, not just the scalp. A simple panel can identify or rule out issues such as anaemia, thyroid dysfunction, or vitamin deficiency, many of which can be treated once identified. That is why a thorough hair loss consultation will often start by reviewing recent blood tests or arranging them as an early step.
What Do Blood Tests for Hair Loss Check For?
Blood tests for hair loss typically look at three main areas: iron stores, thyroid function, and vitamin or hormone levels. Together, these can help identify some of the more common and treatable factors behind excessive shedding.
Iron and Ferritin Levels
Ferritin shows how much iron your body has stored. Low iron levels can contribute to hair thinning and are one of the more common correctable causes. The NHS lists hair loss as a recognised symptom of iron deficiency anaemia, which is diagnosed with a full blood count.
Thyroid Function
A thyroid function test checks whether your thyroid is producing the right amount of hormone. Both an underactive and an overactive thyroid can affect the hair growth cycle. The NHS specifically lists hair loss among the symptoms of an underactive thyroid.
Vitamins and Hormones
Vitamin D and B12 support follicle function, and low levels are common, particularly in colder climates or restricted diets. Hormone panels, including testosterone, are sometimes added when a pattern of loss or other symptoms point towards a hormonal cause.
What Can Your Results Reveal?
Your results may show whether your hair loss has a specific, treatable medical cause or is more likely to be linked to factors such as genetics or ageing. For example, low ferritin may point towards a need to address iron levels, while an abnormal TSH result may indicate that thyroid management needs to be considered alongside any hair treatment.
Normal results do not always give the complete picture. Where your result sits within the reference range can also matter, particularly when investigating hair loss. This is why blood results are best considered alongside your symptoms, hair pattern and medical history, rather than viewed in isolation.
How a Hair Loss Consultation Uses These Results
A hair loss consultation uses your blood test results alongside a scalp examination and your history to build a full picture of what’s driving your shedding. A hair loss specialist can spot patterns a results printout alone won’t show, such as whether nutritional and genetic factors are both contributing at once.
This is where a hair growth specialist adds real value, connecting your numbers to a specific, personalised plan rather than a generic supplement recommendation. If you haven’t had blood tests done recently, a hair loss treatment consultation is a practical place to start.
Get Your Hair Loss Assessed at The Hairology Centre
If you are dealing with unexplained shedding or thinning, your blood results are only useful when they are understood in the context of your hair loss. At The Hairology Centre, our hair loss consultation includes a full history, scalp assessment and guidance on your results, helping you understand what they mean for your next steps.
Start your online assessment today, or book a consultation with our specialists in Marlow or Central London to have your hair loss properly assessed, not just tested.
Frequently Asked Questions
- Can a blood test explain why I’m losing hair?
Yes, a blood test can identify common treatable causes of hair loss, such as low ferritin, an underactive or overactive thyroid, and certain vitamin deficiencies, although it won’t detect genetic pattern hair loss.
- What blood tests are usually done for hair loss?
The most common tests are a full blood count, ferritin, thyroid function (TSH), vitamin D, and vitamin B12, with hormone tests added if your history suggests a hormonal cause.
- Can hair loss happen even if my blood tests are normal?
Yes, results within the normal range don’t rule out a contributing factor, since hair follicles can be more sensitive to borderline levels than the standard reference range implies.
- How soon will I see results after treating a deficiency found on a blood test?
Most people notice a slowdown in shedding within three to six months of correcting a deficiency, though visible regrowth can take longer, given how the hair growth cycle works.
5. Do I need a GP referral before booking a hair loss consultation?
No, you can book a private hair loss consultation directly, though your GP can still arrange blood tests through the NHS if you’d prefer that route first.
6. Will a blood test tell me if I have male or female pattern baldness?
No, pattern hair loss is diagnosed by examining the scalp and hairline, not from blood results, though blood tests are still useful to rule out other contributing causes.
