This year’s winner of the Grand Prix for product design at France’s Cannes Lions International Festival of Creativity is the Lucky Iron Fish. Although it looks like a souvenir shop tchotchke, the small iron fish is actually a brilliant low-tech solution to prevent the health-destroying consequences of anemia.

The surprising design concept was invented by Christopher Charles, a medical student at McMaster University in Canada who traveled to Cambodia in 2008 on an undergraduate research project. In Cambodia, a diet of predominantly rice and fish leaves a large percentage of the population with iron deficiencies that can lead to anemia, a global health problem with effects ranging from an inability to focus to premature births and miscarriages. But iron pills are expensive, and their side effects discourage people from complying with a daily dose.

Charles became obsessed with finding a simple, cost-effective, accessible, and environmentally sustainable solution to the problem. After reading about how using iron pans allows iron to leach into food, he got an idea. While cookware is heavy and costly and wasn’t the right solution for Cambodians, simply placing a lump of iron in a liter of water with a splash of citrus (ascorbic acid helps iron absorption) and boiling it for 10 minutes—either to be used later as drinking water or in soup—could provide up to 75 percent of daily iron needs for a family for up to five years.

It took more than one iteration to arrive at a winning design. The first prototype was a small rectangular bar of iron that locals used as doorstops, paperweights, and to prop up table legs instead of in cooking. A second rounded version allayed fears of scratching cookware but still didn’t stick. Next was a lotus flower, a resonant spiritual symbol in Cambodia that nevertheless didn’t quite catch on for meal prep.

Finally, the fish—a creature that Cambodians consider a symbol of hope and good luck—did the trick. Charles says they distributed 400 fish to five test communities and were surprised to find a 90 percent compliance rate for those who used it daily. Blood testing of the users showed a 50 percent decrease in the incidence of clinical iron deficiency anemia and an increase in users’ iron levels after nine months.

The fish are made by locals using available scrap metal that is screened for quality control. Since 2012, Lucky Iron Fish Inc. has been a commercial enterprise, and you can buy a fish for donation on the company website.