Iron deficiency anaemia is common condition among women. Researchers from Switzerland determine which supplement dosing schedule is most effective for iron absorption.
Iron deficiency anaemia (IDA) is a common condition among women due to their menstrual period. Because of this, iron tablets are often prescribed to be taken daily in order to maintain normal iron levels. However, daily dosing of iron supplements may actually cause decreased iron absorption in the long run.
In an article recently published in Lancet Haematology, a group of researchers from Switzerland did a study to determine whether long-term iron absorption is better when iron supplements are given on alternate days or via split-dosing. The researchers completed two randomized controlled trials to assess this.
In the first trial, women aged 18-40 years old who were diagnosed as iron deficient were assigned into two groups. The first group received a 60 mg iron tablet once a day for 14 days while the other group was asked to take 60 mg iron tablet every other day for 28 days. In the second trial, women were assigned into two groups which were stratified into serum ferritin levels. One group received 120mg iron tablet once a day for 3 days while the other group received two 60 mg iron tablet taken nine hours apart for three days. After 14 days, researchers did a crossover. The group who received the once-daily dosing now took the twice-a-day dose schedule and vice versa. Iron bioavailability and serum hepcidin were then measured as primary outcomes in both studies.
The results show that those who were receiving daily iron supplements had a higher hepcidin level and lower iron absorption when compared to those receiving it on alternate days. Hepcidin is the central regulatory molecule controlling iron absorption, and high levels of hepcidin indicate lower levels of iron absorption. On the second study, the group who received iron supplements via split-dosing had higher hepcidin levels and lower iron absorption.
Overall, and in contrast to previous understanding, providing iron supplements in single doses and on alternate days promotes better iron absorption and may improve clinical outcomes among women with iron deficiency anaemia. Alternate day dosing may also improve compliance and reduce the side effects.
Written by Karla Sevilla
Reference: Stoffel, N.U., et al. (2017). 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. Lancet Haematology. http://dx.doi.org/10.1016/ S2352-3026(17)30182-5