Low-dose Iron Supplementation in Non-anaemic Iron-deficient Women

The established therapy for iron-deficiency today is oral iron supplementation. However, this often leads to side effects such as constipation, black stools, nausea, and abdominal pain. There are some studies that have compared the efficacy of low-dose iron with normal-dose iron. These showed that the side effects are dose-dependent. Furthermore, some studies have shown that the uptake capacity of high-dose iron is less efficient due to the upregulation of hepcidin. In a pilot study with low-dose iron (6mg per tablet), a significant increase in iron was shown, which can be explained by a lower hepcidin release. Therefore, the investigators would like to show the efficacy of the low-dose iron product in a placebo-controlled setting. Furthermore, the goal is to examine the reduction of side effects before and after administration of the iron and placebo tablet. Additionally, a potential increase of low blood pressure to normal blood pressure will be investigated. There will be two groups of women: one group will be given a low-dose iron supplement of two tablets containing each 6mg for 2 months (60 days), the other one will get two placebo tablet for 2 months, accordingly.

Inclusion criteria

• informed consent as documented by signature
• female gender
• premenopausal
• age > 18 years
• regular menstrual cycle
• BMI in normal range (18-25 kg/m²)
• serum-ferritin ≤30µg/l
• no anaemia (Hemoglobin ≥117g/l)
• no intake of dietary supplements containing iron (last 4 weeks)
• the participant is linguistically and cognitively able to understand the study procedure

Exclusion criteria

• Current pregnancy
• breastfeeding
• hypermenorrhea (more than 5 unties/tampons per day)
• chronic inflammatory diseases (e.g. colitis)
• psychiatric disorders
• chronic kidney disease (creatinine >80 µmol/l)
• liver disease (ALT >35 U/l)
• increased CRP (>5mg/l)
• hypersensitivity to iron-supplements
• intake of medicines that interact with oral iron supplementation (e.g. PPI)