Iron Absorption From Iron-fortified Fonio Porridge: a Stable Isotope Study
Condition: Iron Deficiency
MeSH terms: Iron Deficiencies
Study type: Observational

Summary: 
      The study sought to investigate the effect of lowering phytic acid in fonio porridge with
      phytase activity naturally occurring in wheat flour on iron absorption using labelled stable
      isotopes of iron. The study population is represented by 16 apparently healthy young Beninese
      women aged 18-30 years recruited based on their willingness to participate and according to
      inclusion criteria. Test meals consisted of fonio porridges fortified with isotopically
      labelled [57Fe] or [58Fe] ferrous sulfate with and without wheat flour. Meals were
      administered to fasting subjects on two consecutive days using a randomised crossover design:
      half the subjects received the test meal on the first day and the control on the second day
      and vice versa. Venous blood sample were collected (day 1 and day 14) for iron status and
      iron absorption measurement. Iron absorption measurement is based on erythrocyte
      incorporation of iron stable isotope labels 14 days after intake of the labelled test meals
      and calculated based on isotope-dilution.
    

Detailed description: 
      Objective: To compare the bioavailability of iron in fonio porridge fortified with
      isotopically enriched [57Fe] or [58Fe]-ferrous sulfate with and without reducing phytic acid
      by native phytase in wheat flour.

      Study population: Sixteen apparently healthy young women aged 18-30 years recruited at the
      University based on their willingness to participate and according to inclusion criteria.

      Study design: Fonio porridges fortified with isotopically labelled [57Fe] or [58Fe] ferrous
      sulfate, with (test meal) and without wheat flour (control meal) are administered to fasting
      subjects on two consecutive days using a randomised crossover design. Half the subjects
      received the test meal on the first day and the control on the second day and vice versa. No
      food or drink was allowed within the 3 hours after consumption. All meals were administered
      under close supervision. Venous blood sample were collected (day 1 and day 16) for iron
      status and iron absorption measurement. Iron absorption measurement is calculated based on
      iron isotope-dilution in erythrocyte 14 days after intake of the labelled meals.

      Study parameters: Fourteen days before the test, height and weight were measured for
      nutritional status and subjects were screened for pregnancy and malaria. They were also
      treated with antihelminth (albendazole tablet). The day before meals test (day 0), whole
      blood sample was collected for hemoglobin (Hb), serum ferritin (SF), serum Transferrin
      Receptor (sTfR) and C-reactive protein (CRP). Anemia and iron deficiency was defined as Hb <
      120 g/L, and SF < 12 µg/L respectively. Pregnancy test and malaria tests were repeated on
      that day. On day 1 and day 2, the fonio porridges were randomly given to the subjects on a
      cross-over designed. Fourteen days after the meal test (day 16) whole blood sample was
      collected for iron absorption measurement.
    

Intervention name(s): Fe57 and Fe58-FeSO4 stable isotopes
Intervention type(s): Dietary Supplement
Intervention description(s): [57Fe] and [58Fe]- FeSO4 prepared from isotopically enriched 57Fe and 58Fe respectively, by dilution of each compound in 0.1 mol H2SO4/L.
Other intervention name(s): iron ferrous sulfate
Observational model: Case-Only
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        apparently healthy young women of reproductive age (18-30y)
      
Biospecimen description: 
      2 samples of 8 ml venous blood per subject
    
Keywords: ferrous sulfate; iron absorption; Beninese women; fonio