The Hair Loss Bloodwork Panel Every Man Should Get

Before you spend another dollar on hair supplements, get blood drawn. Half the men chasing topicals for a thinning problem are actually shedding because of something a basic blood panel would catch in five minutes. Deficiencies and imbalances are fixable, and fixing them is often the fastest hair win there is. Here is exactly what to test and why.

Why bloodwork comes before supplements

Supplements only help when they correct a real deficiency, a point we make in the hair supplements guide. Without testing, you are guessing, and guessing means buying pills you do not need while missing the one thing actually driving your shed. Bloodwork turns the guesswork into a target list.

Ferritin

Ferritin measures your iron stores, and low ferritin is a well-documented driver of hair shedding, including in men, where it gets overlooked because iron deficiency is assumed to be a women's problem. If you are shedding diffusely across the whole scalp rather than in a pattern, ferritin is the first number to check. More in iron deficiency hair loss.

Vitamin D

Vitamin D is involved in the hair follicle cycle, and deficiency is extremely common in men who work indoors. It has been associated with several forms of hair loss, and it is cheap and easy to correct. See vitamin D deficiency and hair loss.

Thyroid markers

Both underactive and overactive thyroid cause hair shedding, and thyroid problems are easy to miss because the other symptoms are vague. A simple TSH test, with free T4 if needed, screens for it. This is one of the most common reversible causes of diffuse shedding.

Zinc and a full blood count

Low zinc shows up in some shedding cases, and a complete blood count can flag anemia and other issues that show up first in your hair. These round out the picture alongside iron and vitamin D.

Testosterone and related hormones

For pattern loss specifically, your hormone levels matter less than your follicle sensitivity to DHT, but a hormone panel is still worth having for overall context, especially if you have other symptoms like low energy or low libido. Pattern loss is usually about sensitivity, not sky-high testosterone, which is why a DHT blocker at the scalp matters more than your total number.

What to do with the results

Correct what is genuinely low, retest in a few months, and only then judge whether you still have a shed to chase. If your panel is clean and you are losing hair in a pattern, the problem is DHT, not diet, and the fix is topical treatment like our RU58841 and minoxidil serum rather than another bottle of vitamins. Explore the full Reclaim Gang lineup once you know what you are actually dealing with.

FAQ

What blood tests should I get for hair loss?

The core panel is ferritin, vitamin D, thyroid (TSH), zinc, and a complete blood count, with a hormone panel for broader context. These catch the most common reversible causes of shedding.

Can a blood test tell me why I am losing hair?

It can identify reversible drivers like low iron, low vitamin D, or thyroid issues. It cannot diagnose genetic pattern loss, which is identified by the pattern itself rather than a blood marker.

Should I supplement before or after testing?

After. Supplementing blind wastes money and can mask what is actually going on. Test first, correct what is low, then reassess.

Sources: Associations between low ferritin, vitamin D deficiency, thyroid dysfunction, and hair loss are drawn from published dermatology literature.