Many farmers across the western African nation of Gabon share the same grievance: waking up to trampled crops following nighttime raids by hungry forest elephants. But some elephants aren’t just after tasty snacks, as some observant farmers have noticed—the animals often seek out the stems and leaves of banana and papaya plants and leave the nutritious fruit broken on the ground. “That makes farmers even angrier, because they can’t understand why they just damage the fruits and don’t eat them,” says Steeve Ngama, a conservation scientist at Gabon’s National Center for Scientific and Technological Research in Libreville.

But why would elephants eschew the fruit? Forest elephants in Southeast Asia are known to eat certain plants when they’re ill as a kind of self-medication, and Ngama recalled research suggesting that banana and papaya leaves have medicinal properties. Could it be possible, he wondered, that Gabonese farms aren’t just buffets for local elephants but also pharmacies?

Together with other scientists in Gabon, Europe, and the United States, Ngama has now found evidence for this theory. The study, published in Ecological Solutions and Evidence, reports that African forest elephants (Loxodonta cyclotis) are more likely to seek out papaya and banana plants when they’re suffering from gut parasites.