The researchers say they think nuts are good for the heart because they have beneficial effects on blood lipids, including cholesterol. Many also contain arginine, a substance that helps the body to relax. Most nuts contain similar nutrients so the researchers said that peanuts were also beneficial - except those with added hydrogenated fat. Walnuts appeared to be the top nut in terms of health as they also contain a high level of linolenic acid, which has been linked to reduced risk of heart disease. The researchers based their study on the Mediterranean diet which is rich in nuts.
People living in Mediterranean countries are less likely to suffer heart disease.