Hair loss is a common concern among women, and iron deficiency has long been suspected as a contributing factor. A well-designed systematic review and meta-analysis published in Skin Appendage Disorders examined the relationship between iron deficiency and nonscarring alopecia in women, including conditions such as diffuse hair shedding (telogen effluvium) and female pattern hair loss.
The researchers analysed data from 36 studies involving more than 10,000 women, comparing iron levels in women with nonscarring hair loss to those without hair loss. The key marker of interest was serum ferritin, which reflects the body’s iron stores rather than circulating iron alone.
The analysis found that women with nonscarring alopecia had significantly lower ferritin levels compared with control groups. On average, ferritin levels were approximately 18 ng/mL lower in women experiencing hair loss. Importantly, when iron deficiency was defined using a more clinically sensitive threshold (ferritin below 30–40 ng/mL), nearly 60% of women with hair loss were found to have low iron stores.
Interestingly, the study showed that iron-deficiency anaemia (low haemoglobin) was not consistently more common in women with hair loss. This suggests that hair loss may be associated with low iron stores even in the absence of anaemia, meaning standard blood counts alone may miss an underlying issue relevant to hair health.
The authors concluded that while iron deficiency is unlikely to be the sole cause of hair loss, suboptimal ferritin levels are common in women with nonscarring alopecia and may play a contributory role. They suggest that assessing and correcting low ferritin could be clinically relevant when evaluating women with unexplained hair loss.
Key takeaway
This research supports the view that ferritin testing can be useful in women with nonscarring hair loss, even when haemoglobin levels are normal. However, iron supplementation should always be guided by a healthcare professional, as excess iron can be harmful.
Reference:
Iron Deficiency and Nonscarring Alopecia in Women. Skin Appendage Disorders.
https://karger.com/sad/article/8/2/83/826740/Iron-Deficiency-and-Nonscarring-Alopecia-in-Women
