For years, you've heard that a Mediterranean diet – one that's rich in fruits, vegetables, good-for-you fats, and red wine – might protect your heart. Now there's no question. A landmark study published in the 'New England Journal of Medicine' in February confirms that this style of eating slashes risk of heart attack, stroke, and cardiovascular disease-related death by a staggering 30 percent.

Spanish researchers divided 7,447 adults into three diet groups: a Mediterranean diet along with 1 liter of extra-virgin olive oil per week, a Mediterranean diet with 30 grams of mixed nuts per day, or a low-fat diet. Both Mediterranean groups had so many fewer cardiovascular issues than the low-fat dieters that researchers cut the trial short after four and a half years.

But what's most shocking is that all of the participants were fat, had high cholesterol or diabetes, or smoked cigarettes, putting them at high risk for heart troubles. So this study proves that diet, and diet alone, can spare you a cardiovascular-related death, independent of exercise and other healthy lifestyle factors. "Lots of research on the Mediterranean diet has looked at heart disease patterns within populations, but this is the first large-scale trial to actually demonstrate cause and effect – and use death as an endpoint," says Rachel Johnson, professor of nutrition at the University of Vermont and a spokeswoman for the American Heart Association.

So what makes olive oil, onions, and Merlot magic? "It's the combined effect of many Mediterranean diet components, not one particular ingredient, that promotes heart health," says senior study author Dr. Miguel Martínez-Gonzalez. First, he says, is the abundance of mono- and polyunsaturated-fats, which lower LDL (bad) cholesterol. You also get tons of phytonutrients from fruits and veggies and antioxidants from red wine, all of which tame inflammation, a primary cause of heart troubles. Plus, the Mediterranean diet involves limiting red meat, dairy, and processed and high-sugar foods, all major inflammation triggers.

"Overall, this diet reduces inflammation," says Dr. Dennis Goodman, professor of medicine at New York University. "Add in the nutritional benefits of vegetables and wine, and you get a recipe for decreasing cardiac death."