A Loma Linda University medical study published results that should encourage us all to eat a 3 to 3 1/2-ounce serving of nuts five or more times a week. Those participants who ate nuts five times a week throughout the study showed a decrease in their LDL (the bad cholesterol) levels as well as total cholesterol levels.

Those with lower cholesterol readings were at a lower risk for heart attack. It may be interesting to note that in spite of the intake of 35% of calories from primarily monounsaturated fat, participants showed no significant weight increase.
Kathleen E. McMahon, PhD, RD, writes on behalf of the California Pistachio Commission, "Current status of research on monounsaturated fats in nuts demonstrates that eating nuts can play a role in lowering coronary heart disease risk by decreasing both total cholesterol and LDL cholesterol levels."
Pistachios are rich in phytosterols, known for lowering blood cholesterol. Animal studies have shown that phytosterols may have anti-cancer properties. According to the 2000 USDA Dietary Guidelines that recommend a diet low in saturated fat and cholesterol, pistachios are an ideal food.
In the well-known DASH diet study, eating 4 to 5 servings of nuts per week played an important role in lowering blood pressure in patients with hypertension. Minerals such as potassium, magnesium, and calcium, found in pistachios are important in maintaining normal blood pressure.
Pistachios are a key player in the highly respected Mediterranean diet as well and are considered one of the major components of the diet. Studies revealed that those on the Mediterranean diet had a lower risk for heart disease and hypertension.
In numerous medical studies comparing dietary data of vegetarian and plant based diets to standard American diets, vegetarians and vegans consistently register the lowest rates of chronic diseases and the longest life expectancy. An important staple of the plant-based diet is nuts and seeds.