Randomized trial of guava as source of ascorbic acid to reduce iron deficiency among indigenous schoolchildren in northern Mexico

Abstract

This trial aimed at examining the effect of drinking 300 ml of guava juice containing 200 mg of ascorbic acid (AA) with the main meal for 10 weeks (5 d/wk) on the iron status of iron‐deficient children. A total of 295 children aged 6–9 years from 4 boarding schools were screened for anemia using altitude‐adjusted capillary hemoglobin (Hb) cut‐offs. The 95 anemic children were randomly allocated to a guava or placebo group, each with 16 and 14 iron‐deficient children (serum ferritin‐SF <12 ng/ml with negative C‐reactive protein), respectively. The placebo group was given guava‐flavored juice free of AA. Children with fecal parasites were treated. Dietary intake was collected for weeks 3, 5 and 7 at school and household level. Differences in mean Hb and SF between the groups at the end of the trial were the main outcomes. Dietary iron intake did not differ significantly between the guava and placebo groups at school (25 vs. 24 mg/d; p 0.3) and household level (19 vs. 20 mg/d; p 0.3). Baseline mean‐s.d. venous Hb (g/l) and SF (ng/ml) were 120‐6 and 8.2‐3.5 for the guava, and 115‐13 and 7.4‐4.6 for the placebo group, respectively (Hb: p 0.2; SF: p 0.6); at the end of the study these were 130‐7 and 17.9‐10.3, and 126‐15, and 15.4‐5.8 (Hb: p 0.4; SF: p 0.4). No differences on the iron status were found between the children who received guava and placebo juice after 10 weeks. Study supported by grant IMSS‐FOFOI/2005/1/I/029 and CDI‐Chihuahua