Otago and Cambodian researchers conducted a randomised trial of the effectiveness of the powder in reducing anaemia and iron deficiencies among 3112 6-month-old infants in rural Cambodia.
The powder, provided in sachets, contains a blend of iron and other micronutrients, and is easily mixed into home-prepared foods.
Study lead author Dr Susan Jack, a medical doctor, said these "exciting findings", recently published online in the journal Archives of Pediatrics & Adolescent Medicine, were likely to be of wider international interest, including in other developing countries.
Iron deficiency anaemia in infants is a global health problem, but has its greatest impact in poorer countries.
"Anaemia represents a major public health concern as it can cause cognitive and learning difficulties and is associated with increased mortality," Dr Jack said.
Dr Jack, who is a PhD student at Otago University's Centre for International Health, said it was estimated in Cambodia that 55% of children under 5 were anaemic and 40% had stunted growth.
Infants in the study were divided into a control and intervention group.
Both groups of caregivers received education about the importance of continued breastfeeding and good complementary feeding.
Intervention group caregivers were also given micronutrient sachets to use in daily feeding for six months.
Compared with the control group, after 12 months the prevalence of any anaemia in the micronutrient group was reduced by 20% and moderate anaemia by 27%.
After 12 and 18 months, iron deficiency prevalence - a risk factor for developing anaemia - was reduced by 24% and 12% respectively in the micronutrient group.
Childhood anaemia could have life-long effects, including by contributing to learning difficulties, and potentially lower educational achievement.
This study provided "clear evidence" supporting the introduction of the powder sachets in Cambodia and similar settings, Dr Jack said.
The Cambodian Ministry of Health had decided to make the powder available for children aged between 6 months and 2 years.
"I think it's great that Otago University is contributing to improving the lives of people in low-income countries."
