Walnuts...

Like almonds, walnuts are rich in heart-healthy antioxidant vitamin E, potassium, and magnesium, but they really shine thanks to a good dose of omega-3 fatty acids. Just one quarter-cup serving contains nearly 95 percent of your daily dose.

How they help: Walnuts lower LDL cholesterol, help regulate blood pressure, and protect against excessive clotting and inflammation. Omega-3 fatty acids are antiatherosclerotic, meaning they help prevent (and may even reverse) atherosclerosis, the progressive thickening and hardening of the artery walls created by fatty deposits. In other words, omega-3 fats are the "good fat" you've heard about, and they're fantastic at fighting deadly atherosclerotic heart disease.

Snack smart: A good portion of the nutrients in a walnut is found in its skin, so go for whole, raw nuts with the skins on. Consuming omega-3 fatty acids three to four times a week is a good thing -  so just grab a handful and munch.