Fish fits well in a healthy diet since it replaces red meat, which has a heavy load of saturated fat. But fish may go farther than that. A certain type of fat in fish oil (omega-3 fatty acids) may actually be good for the heart.

Researchers began to explore the possible cardiovascular benefits of fish oil some 20 years ago when they first noted that Greenland Eskimos rarely developed coronary heart disease.

Heredity does not account for this - Eskimos who migrate to other countries eventually...