Fortified rice may raise risk of hookworm infections

Fortification of staple foods is considered an effective and safe strategy to combat micronutrient deficiencies, thereby improving health. While enhancing micronutrient status might be expected to have positive effects on immunity, some studies have reported increases in infections or inflammation after iron supplementation.
 
Against this background, an international team of scientists conducted a research project aimed to quantify the impact of multi-micronutrient fortified rice, which was distributed through the World Food Program (WFP) school meal programme as a single meal per day. The study focused on micronutrient status, health and cognition of the Cambodian schoolchildren participating in the WFP programme. As uncertainly exists on the most optimal combination of micronutrients to be added to rice, three different types of fortified rice, with different micronutrient composition, were studied. The study is meant to find out which effects the introduction of fortified rice has on hookworm infection and local intestinal inflammation in Cambodia.
 
The researchers analysed faecal samples from about 2,000 children at 16 primary schools that are participating in a UN World Food Programme initiative which provides daily meals of fortified rice to schoolchildren. The schools were randomly split into four groups: children in one group ate plain, ‘placebo’ rice, while the other groups received three different types of rice fortified with micronutrients including iron, zinc, folate and different vitamins.

After three and seven months, the researchers measured levels of intestinal parasite infections. The study showed that micronutrient-fortified rice significantly increased risk of new hookworm infection. It was published in the open access .journal  PLOS One in January 2016.

The researchers conclude from the outcome of the study that consumption of rice fortified with micronutrients can increase hookworm prevalence, especially in environments with high infection pressure. When considering fortification of staple foods, a careful risk-benefit analysis is warranted, taking into account severity of micronutrient deficiencies and local prevalence of parasitic infections.
 “There is absolutely an important role to play for fortified rice, but it should be tailor-made to the local situation,” says Frank Wieringa, a co-author of the study working at the French Research Institute for Development and based in Phnom Penh, the Cambodian capital.

References
Brechje de Gier and others Micronutrient-fortified rice can increase hookworm infection risk: a cluster randomized trial (PLOS One, 6 January 2016)

(SciDev/wi)