In 2008, Christopher Charles was living in Cambodia and researching anemia. The condition, which is commonly caused by iron deficiency, afflicts roughly half of Cambodia’s children and pregnant women. Untreated, it can lead to lethargy, impaired growth and cognitive development in children, and increased risks of premature delivery and maternal mortality.

Charles, a Canadian epidemiologist, knew that iron-rich foods and supplements were too expensive for most rural Cambodians. Even cast-iron pots, which safely transmit iron to food as it cooks, were out of reach. But he wondered whether a small piece of iron placed in a standard aluminum pot would have a similar iron-releasing effect. To test his hypothesis, Charles distributed blocks of iron to local women, telling them to place the blocks in their cooking pots before making soup or boiling drinking water. The women promptly put them to use as doorstops.

After talking with village elders, Charles learned of a fish known as try kantrop, which the locals ate frequently and considered a symbol of good luck. When he handed out smiling iron replicas of this fish, women started cooking with them. “People associated it with luck, health, and happiness,” he says. Within 12 months, Charles reports, anemia in villages where the fish was distributed virtually disappeared.

The genius of the Lucky Iron Fish is that it does not have to be shaped like a fish. “If we were to go to sub-Saharan Africa,” says Charles, “or a dry area where fish is not an important part of the diet, we could very easily change it to a different symbol of luck.”

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