The Mediterranean diet, hailed as possibly the world’s healthiest, may have some new competition. A recent study in the Journal of Internal Medicine suggests that a Nordic-style regimen—which emphasizes berries, canola oil, fatty fish, whole grains, and root vegetables—may help protect your heart. When people with signs of metabolic syndrome (the cluster of symptoms that raises heart disease, stroke, and diabetes risk) were put on this plan for four to six months, they saw a significant drop in bad cholesterol and a better ratio of HDL to LDL readings, thanks to the plethora of healthy fats and fiber. The diet is also antiinflammatory, which may help prevent diabetes, says study author Matti Uusitupa, M.D., Ph.D., a professor at the University of Eastern Finland. Put your diet on the Nordic track…