The European Food Safety Authority’s (EFSA) Panel on Dietetic Products, Nutrition and Allergies (NDA) said the article 13.5 emerging and proprietary science dossier did not demonstrate causality between ferrous sulphate (the iron form) consumption and, “reduction of excessive hair loss”.
Pierre Fabre Dermo-Cosmétique submitted the claim for 18-49-year-old, post-menopausal women experiencing excessive hair loss. It contained five observational studies and one review.
The NDA discounted two of the observational studies, “no tests were performed to exclude individuals with raised serum ferritin owing to inflammation/infection.”
Another cross-sectional observational study looked at 418 women aged 13-81 but the NDA said no correlation was shown between iron concentrations in the women’s blood and telogen effluvium (hair loss).
Another cross-sectional study was similarly inconclusive, the NDA found, as iron levels in the telogen effluvium group were not lower than controls.
In a case-control study among 15-45-year-olds, iron levels were lower in the hair loss group – and iron-binding capacity was higher than in controls – the NDA acknowledged a low iron-hair loss association.
But it said the results were compromised by the fact the study, “was not controlled for environmental and physiological factors which might have influenced iron status besides iron intake, or for factors other than iron status which might have influenced hair loss.”
Overall it noted a similar observation and concluded, “that a cause and effect relationship has not been established between the intake of iron and maintenance of normal hair growth.”
Pierre Fabre Dermo-Cosmétique proposed that iron could reduce hair loss because it is contained in haemoglobin, the tissue oxygen transporter, “including the hair follicles where oxygen is required for mitotic activity.”
The dossier noted that iron is an essential cofactor for ribonuclease reductase, involved in DNA synthesis.
It therefore proposed that, “iron deficiency might reduce the proliferation of hair follicle matrix cells, which might lead to an impaired hair growth and to an accelerated hair loss.”
The NDA opinion can be found here.