In 1971, a team of Danish researchers found that an Inuit population in Greenland had lower cholesterol levels and incidence of heart disease than Danes and Inuits who lived in Denmark. A theory arose: The indigenous people’s high marine-fat diet gave them heart protections.
Since then, fish oil and omega-3 fatty acids — the health-boosting star component of fish oil — have been the subject of tens of thousands of papers exploring their health benefits.