Previously we have written several blog posts about iron deficiency and anemia, different iron salts, menstruation and iron deficiency among toddlers. In this blog post we focus on how to take iron supplements – how to optimize taking iron supplements and what has new research found?
Until now, it has been suggested taking iron supplements daily during iron treatment. Bigger iron doses should be divided during the day to increase iron absorption through the gut. In case of latent iron deficiency (a situation, when blood sample shows normal hemoglobin level but iron stores have decreased), it is enough to take 30–40 mg of iron bisglycinate during 3–4 months. This suggestion is for the daily iron intake. Filling up iron stores takes up to half a year, therefore, the real length of iron treatment depends on a person´s iron stores and iron absorption. In case of anemia, daily iron intake for iron bisglycinate should be 60–120 mg (Nôgel Superraud 1-2 pills per day).
Did you know that…
in 2001, research found that an acute phase protein hepcidin regulates iron metabolism? Hepcidin is a hormone, which regulates iron absorption and it is produced by the liver. The liver has the most important role in iron metabolism. Hepcidin binds with ferroportin (the most imporant protein transporting iron in our bodies) and weakens ferroportin´s activity. Low hepcidin level increases iron absorption and high hepcidin level decreases iron absorption. Hepcidin just like ferritin (both are acute phase proteins) have higher values in case of inflammatory bowel diseases. Iron is not well absorbed by people suffering from inflammatory bowel diseases. Iron supplementation can worsen a person´s gut problems, which can lead to even weaker iron absorption [1].
In an open randomized trial carried out in 2017 in Switzerland, women with iron deficiency aged 18–40 with serum ferritin levels below 25 μg/L were examined. Women were divided into two groups: in the first group women took iron supplementation 60 mg every morning for 14 days. In the second group women took iron supplementation every other day 60 mg for 28 days. In the end of the trial (14 and 28 days) iron absorption was higher in the second group, where iron was taken every other day. The difference between the two groups was 5.5%. The cumulative iron absorption was 44,3 mg higher in the second group. In the first group, women had higher serum hepcidin levels compared to the second group [3].
Should you divide higher iron dosages throughout the day or should iron be taken as a single dose?
In the same trial carried out in 2017 it was found that iron absorption was optimized when iron was taken every other day as a single dose compared to taking iron every day and dividing dose throughout the day. When iron was taken every day in the trial and dose was divided throughout the day, women had higher hepcidin level. High hepcidin level decreases iron absorption [3].
There are only a small number of such research, but trial carried out in Switzerland is of high importance for iron deficiency anemia treatment. Taking iron every other day is especially important to people, who suffer from weak iron absorption through the gut and who suffer from inflammatory bowel diseases.
If you have been advised to take iron every day for 3 months, you can take iron every other day for 6 months. Taking iron every other day prolongs the treatment time, but can increase iron absorption. Also iron is less likely to cause side effects linked to iron supplementation when taking iron every other day.

Hepcidin regulates iron transport into plasma. When hepcidin level is low, ferroportin´s (Fpn) molecules transport iron into plasma. When hepcidin level is high, hepcidin binds with ferroportin and weakens ferroportin´s activity. Therefore, less iron is transported into plasma [2].
Sources:
[1] E.Rossi. Hepcidin – the Iron Regulatory Hormone. Clin Biochem Rev. 2005 Aug; 26(3): 47–49.
[2] T.Ganz.Molecular Control of Iron Transport. JASN February 2007, 18 (2) 394–400.
[3] N.Stoffel et al. Iron absorption from oral iron supplements given on consecutive versus alternate days and as single morning doses versus twice-daily split dosing in iron-depleted women: two open-label, randomised controlled trials.The Lancet Haematology. Volume 4, issue 11, PE524-E533, November 01, 2017.