Significance of iron status in hair loss in women.

Abstract

Sir, We read with interest Sinclair's recent study1 concluding that there is no clear association between chronic diffuse telogen hair loss in women and low iron stores. At a recent international meeting attended by many of the world authorities on hair disorders (European Hair Research Society, Brussels, 27–30 June 2002) we hosted an open debate on the topic of diffuse hair loss in women, particularly concentrating on the role of iron.2 Sinclair's findings are in support of our clinical experience and interpretation of the literature—that the significance of iron deficiency in hair loss is dubious, despite textbook references to the contrary.3, 4 In our opinion, there are several limitations with respect to the literature concerning this possible association and these include: (i) variation in the biochemical definition of iron deficiency by gender and between laboratories; (ii) difficulty in isolating iron status from other variables that affect hair growth; (iii) lack of confirmation of iron deficiency as a relevant cause of hair loss by replacement therapy with meaningful follow‐up over time; and (iv) lack of consensus regarding the ideal means of measuring hair growth and response to therapy.5 Indeed, the first limitation has been the subject of hot debate just recently.6, 7 It must also be pointed out that some of the more emphatic papers suggesting a significance for iron status in hair loss have really only examined small numbers of women.8 While one may argue that Sinclair's period of follow‐up is too short to detect meaningful regrowth (which he acknowledges), one would certainly expect a reduction in shedding in those women in whom iron status was relevant (and this was not observed in his study). For the reasons stated above, in our hair clinic we too are reluctant to attribute chronic and diffuse hair loss in women to iron deficiency too readily when, in reality, this is usually more likely to be due to androgenetic alopecia or chronic telogen effluvium. It is equally curious to us why young women and even girls with iron deficiency due to menorrhagia rarely present to dermatologists with hair loss!