A snack food that's actually good for you... and may help you live longer.

FOX News Radio's Lisa Lacerra reports:

People who eat nuts seven or more times a week are 20% less likely to die of cancer or heart disease than those that don't eat them, according to Harvard University researchers who conducted a 30 year study - the largest ever done. They tracked 119,000 men and women and found those who had nuts roughly every day were 20% less likely to die during the study period than those who never ate them. In 2003, the FDA said a handful of nuts as part of a low-fat diet may lower the risk of heart disease. They recommend four servings of unsalted nuts a week. But be warned, nuts have a lot of nutrients, but they also have a lot of calories.

Lisa Lacerra, FOX News Radio.