Dual fortification of salt with iodine and iron: a randomized, double-blind, controlled trial of micronized ferric pyrophosphate and encapsulated ferrous fumarate in southern India

• Published in: The American journal of clinical nutrition 2008-11, Vol.88 (5), p.1378-1387
• Main Authors: Andersson, Maria, Thankachan, Prashanth, Muthayya, Sumithra, Goud, Ramakrishna B, Kurpad, Anura V, Hurrell, Richard F, Zimmermann, Michael B
• Format: Article
• Language: English
• Subjects: Adolescent; Anemia, Iron-Deficiency - epidemiology; Anemia, Iron-Deficiency - prevention & control; Biological and medical sciences; Biological Availability; Child; child nutrition; Child Nutritional Physiological Phenomena - physiology; Child, Preschool; common salt; cote-divoire; deficiency anemia; Diet; Diphosphates; disease prevalence; Double-Blind Method; encapsulation; Feeding. Feeding behavior; Female; Ferritins - blood; Ferrous Compounds; ferrous fumarate; food fortification; Food, Fortified; fortified foods; fortified salt; Fundamental and applied biological sciences. Psychology; Goiter - epidemiology; Goiter - prevention & control; hemoglobin; Hemoglobins - analysis; Humans; India - epidemiology; Iodine - administration & dosage; Iodine - analysis; Iodine - deficiency; Iodine - therapeutic use; Iodine - urine; Iron; Iron - blood; Iron Deficiencies; iron deficiency anemia; Iron, Dietary - administration & dosage; Iron, Dietary - analysis; Iron, Dietary - therapeutic use; Male; micronized ferric pyrophosphate; nutrient reserves; Nutrition; nutrition assessment; nutritional intervention; nutritional status; Prevalence; pyrophosphates; randomized clinical trials; relative bioavailability; Rural areas; Rural Health; Rural health care; Salt; school children; school-aged children; sodium chloride; Sodium Chloride, Dietary - administration & dosage; Sodium Chloride, Dietary - analysis; Sodium Chloride, Dietary - therapeutic use; stability; thyroid-function; Treatment Outcome; urinary iodine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; zinc protoporphyrin
• ISSN: 0002-9165; 1938-3207
• DOI: 10.3945/ajcn.2008.26149

BACKGROUND:Dual fortification of salt with iodine and iron could be a sustainable approach to combating iodine and iron deficiencies. OBJECTIVE:We compared the efficacy of dual-fortified salt (DFS) made by using 2 proposed contrasting formulas--one fortifying with iron as micronized ground ferric pyrophosphate (MGFePP) and the other with iron as encapsulated ferrous fumarate (EFF)--with the efficacy of iodized salt (IS) in schoolchildren in rural southern India. DESIGN:After stability and acceptability testing, a double-blind, household-based intervention was conducted in 5-15-y-old children (n = 458) randomly assigned into 3 groups to receive IS or DFS with iron as MGFePP or EFF, both at 2 mg/g salt. We measured hemoglobin, iron status, and urinary iodine at baseline, 5 mo, and 10 mo. RESULTS:Median serum ferritin and calculated median body iron improved significantly in the 2 groups receiving iron. After 10 mo, the prevalence of anemia decreased from 16.8% to 7.7% in the MGFePP group (P < 0.05) and from 15.1% to 5.0% in the EFF group (P < 0.01). The median urinary iodine concentration increased significantly in the IS and EFF groups (P < 0.001) but not in the MGFePP group. Losses of iodine in salt with 1.8% moisture were high for MGFePP, whereas the EFF segregated in salt with 0.5% moisture and caused color changes in some local foods. CONCLUSIONS:Both DFSs were efficacious in reducing the prevalence of anemia and iron deficiency in school-age children. Local salt characteristics should be taken into consideration when choosing an iron fortificant for DFS to achieve optimal iodine stability and color.