Alternate Day vs. Daily Iron Supplementation in Iron Depleted Women in the Philippines

Comparing Oral Iron Supplementation Using Alternate-day Dosing to the Standard of Care Consecutive-day Dosing in Iron-depleted Women With or Without Mild Anemia: a Randomized Controlled Trial in the Philippines

Iron is very important for our body and performs vital tasks. Iron deficiency is a worldwide health problem. The prevalence of anemia in women of reproductive age in Southeast Asia is estimated to be 46.6% in 2019, with iron deficiency being one of the main reasons for anemia. There are different approaches to treat iron deficiency. One of them is the use of iron supplements. Recommended iron supplement treatments today often differ in dose, regimen and length. Experts recommend a dose of 80-200 mg of iron taken either daily or on several days per week, depending on the severity of the iron deficiency (with or without anemia). From certain guidelines lower amounts of iron are also recommended, as this could lead to fewer side effects.Previous studies have shown that both daily and multiple days per week administration can be effective in treating iron deficiency. Recently, several successive iron supplementation studies in Zurich showed that 24 h after ingestion of an oral dose of >60mg iron, the absorption of iron in the body is impaired. In addition it was measured that iron supplements taken only every other day instead of every day are absorbed about 30-50% better and have fewer side effects. Little is known about the long-term effect of this alternating regimen on iron status and side effects.With this 6-months study in the Philippines, the investigators want to compare two different supplementation regimens with oral iron to see if there is any difference in the iron status, intestinal inflammation levels, and side effects, and therefore if it would be better to take the iron supplements every 2 days instead of daily.

Inclusion Criteria:

• Female, 18 to 45 years old,
• SF levels <25 µg/L,
• Hb levels 11-15.5 g/dL
• Normal Body Mass Index (18.5-25 kg/m2),
• In possession of a mobile phone on which the study app can be loaded
• Signed informed consent

Exclusion Criteria:

• Elevated CRP > 5 mg/L
• Any metabolic, gastrointestinal, kidney or chronic disease such as diabetes, renal failure, hepatic dysfunction, hepatitis, hypertension, cancer or cardiovascular diseases (according to the participants own statement) affecting iron metabolism,
• Use of medication which may interfere with iron absorption, gut physiology and iron metabolism
• Consumption of iron supplements within 2 weeks prior to study start and of additional iron supplements during the study period
• Difficulties with blood sampling,
• Known hypersensitivity or allergy to iron or placebo capsules in the given amount (ferrous sulfate, mannitol, silica)
• Pregnancy, breastfeeding
• Known or suspected non-compliance, drug or alcohol abuse
• Cigarette smokers