Hair loss and hair thinning are concerns that affect many people at different stages of life. While genetic factors are often associated with pattern hair loss, several biological and metabolic factors may also influence hair follicle health.
Blood testing can play an important role in identifying underlying factors that may contribute to hair thinning or increased hair shedding. By evaluating key biomarkers, clinicians can assess whether nutrient deficiencies, hormone imbalances, or metabolic conditions may be influencing hair growth.
One of the most commonly tested biomarkers in cases of hair loss is ferritin. Ferritin measures the amount of iron stored within the body. Iron is essential for oxygen transport and cellular metabolism, both of which are important for healthy hair follicle function.
When ferritin levels are low, hair follicles may receive reduced oxygen supply, which can affect the hair growth cycle. This may lead to increased hair shedding or slower hair regrowth. Individuals with low ferritin levels may also experience fatigue, weakness, and reduced exercise capacity.
Vitamin D is another nutrient that plays a role in hair follicle health. Research has shown that vitamin D receptors are present within hair follicles, suggesting that vitamin D may influence hair growth regulation. Low vitamin D levels have been associated with several types of hair loss, including telogen effluvium and alopecia areata.
Vitamin D deficiency may also affect immune function and inflammatory processes, which can indirectly influence hair health.
Thyroid hormones are also important when evaluating hair loss. The thyroid gland regulates metabolism and energy production throughout the body. Both overactive and underactive thyroid function can disrupt the hair growth cycle, leading to diffuse hair thinning across the scalp.
Symptoms associated with thyroid imbalance may include fatigue, weight changes, sensitivity to temperature, and changes in hair texture or density.
Hormones such as testosterone and oestradiol can also influence hair growth patterns. In individuals with genetic predisposition to pattern hair loss, certain hormones may contribute to hair follicle miniaturisation over time.
Blood testing may include measurements of hormone markers such as testosterone, SHBG, and related endocrine biomarkers.
Comprehensive blood testing for hair loss may include ferritin and iron levels, vitamin D, zinc, thyroid hormones, and hormone markers. Understanding these biomarkers can help identify biological factors that may influence hair growth and overall scalp health.