What will have the biggest impact on people's lives and on the global economy? It's rather simple: feed people.

Dancing around jobs, technological advances, disease riddance, social justice, environmental concerns, governance and fair wages are all admirable issues that attract many impact investment programs and, in turn, investors. But malnourishment is a big deal that deserves a lot more attention and impact investment dollars. I'll get to healthy foods in a minute, but for now, let's concentrate on feeding people.

Malhourishment costs the global economy $125 billion. According to a recent report by Save The Children, being malnourished in the womb causes development deficiencies that reduce a child’s future earning potential by 20 percent. Total these deficiencies and by 2030 you lose $125 billion, the global charity figured.

Save The Children monitored 3,000 children in developing countries. Children who were malnourished scored 7 percent lower on maths tests and were 19 percent less likely to be able to read a simple sentence by the time they were 8 years old, compared with properly nourished children. The undernourished were also 12 percent less likely to be able to write a simple sentence and 13 percent less likely to be in the appropriate grade for their age at school. [Read the full report here.]

This bleeds into earning potential, cutting it, researchers found, by one-fifth.

The charity’s development index calculates that overall progress on improving child education has been 32 percent and child health, 23 percent, but nutrition has only improved 13 percent since the mid-1990s.

There is a big push for healthy foods here in the United States, both at home and at schools. But oftentimes we forget some people can't even afford to eat, never mind eat healthy. Which is why impact investors should step in to feed the hungry. It's a big market with incredible potential: better lives for children.