Given the high prevalence of
micronutrient deficiencies and
infectious diseases in infants in developing countries, an evaluation of the efficacy of different
micronutrient formulations on infant morbidity is a priority. The efficacy of weekly supplementation of four different
micronutrient formulations on
diarrhea and acute lower respiratory
infection (ALRI) morbidity was evaluated in Bangladeshi infants. In a double-blind, randomized, controlled community trial, 799 infants aged 6 mo were randomly assigned to one of the following 5 groups: 1) 20 mg elemental
iron with 1 mg
riboflavin, 2) 20 mg elemental
zinc with 1 mg
riboflavin, 3) 20 mg
iron and 20 mg
zinc with 1 mg
riboflavin, 4) a
micronutrient mix (MM) containing 20 mg
iron, 20 mg
zinc, 1 mg
riboflavin along with other minerals and
vitamins and 5) a control treatment, 1 mg
riboflavin only. Health workers visited each infant weekly until age 12 mo to feed the supplement and to collect data on
diarrhea and ALRI morbidity.
Hemoglobin, serum
ferritin and serum
zinc levels of a sample of infants were measured at 6 and 12 mo. Compared with the control group, at 12 mo, serum
ferritin levels were higher in the
iron +
zinc group, and serum
zinc levels were higher in the
zinc and
iron +
zinc groups. Simultaneous supplementation with
iron +
zinc was associated with lower risk of severe
diarrhea, 19% lower in all infants and 30% lower in less well-nourished infants with weight-for-age Z-score below -1.
Iron +
zinc supplementation was also associated with 40% lower risk of severe ALRI in less well-nourished infants. MM supplementation was associated with a 15% higher risk of
diarrhea in all infants and 22% higher risk in less well-nourished infants. Intermittent simultaneous supplementation with
iron +
zinc seems promising; it will be useful to determine whether higher doses would provide greater benefits.