Half of the world's children under the age of 5 have anemia, according to a report from the World Health Organization. They found that children in high poverty regions are particularly at risk for the condition. For example, about 70 percent of African and 65 percent of Southeast Asian preschool-aged children struggle with anemia.

Childhood anemia has long-lasting negative consequences, according to a report that appeared in the Scandinavian Journal of Nutrition. "In iron-deficient children, striking behavioural changes are observed, such as reduced attention span, reduced emotional responsiveness and low scores on tests of intelligence," the report said.

Until recently, the normal treatment for anemic children in poor countries was an iron supplement delivered in pill or syrup form. Although the supplements were effective at treating anemia, they often left children with upset stomachs, reported Sam Loewenberg for the New York Times, not to mention a bad taste in their mouths.

But a new iron supplement called Sprinkles, invented by University of Toronto professor of pediatrics Dr. Stanley Zlotkin, provides an easier way to treat this pervasive childhood health problem.

"Sprinkles, a specially coated, powdered form of the (iron) supplement, is simply added to the child's normal food — usually a rice or corn porridge of some type — and has none of the other side effects or bad taste," Loewenberg wrote.

A group of economists met in 2008 at the Copenhagen Consensus to determine the world’s most effective aid interventions. They put micro-nutrient supplements like Sprinkles at the top of the list. They estimate the cost of providing vitamin A and zinc to 80 percent to the children lacking them would cost $60 million per year. The benefits of this treatment would be worth more than $1 billion, they estimated. They also said that vitamin supplements could reduce mortality for preschool-aged children by 23 percent.

And while micro-nutrients like Sprinkles reportedly are extremely effective, distribution continues to be a problem. Loewenberg summarizes the problem this way: "It is one thing to invent a great new tool, it is quite another to get people to use it. Yet in the world of public health, distribution is usually an afterthought. Much of the focus is on breakthrough drugs, silver bullet vaccines and sprawling, megabudget projects like the $6.6 billion dollar American anti-AIDS program Pepfar, which accounted for 75 percent of the Obama administration’s global health budget in fiscal year 2012."