As the Inuit people spread across the Arctic, they developed one of the most extreme diets on Earth. They didn’t farm fruits, vegetables or grains. There weren’t many wild plants to forage, aside from the occasional patch of berries on the tundra.

For the most part, the Inuit ate what they could hunt, and they mostly hunted at sea, catching whales, seals and fish. Western scientists have long been fascinated by their distinctly un-Western diet. Despite eating so much fatty meat and fish, the Inuit didn’t have a lot of heart attacks.

In the 1970s, Danish researchers studying Inuit metabolism proposed that omega-3 fatty acids found in fish were protective. Those conclusions eventually led to the recommendation that Westerners eat more fish to help prevent heart disease and sent tens of millions scrambling for fish oil pills.

Today, at least 10 percent of Americans regularly take fish oil supplements. But recent trials have failed to confirm that the pills prevent heart attacks or stroke. And now the story has an intriguing new twist.