We love nuts, and luckily they're some of the healthiest foods on the planet—especially if you're looking for a protein-packed snack in a nutrient-dense package. While they're high in fat (nuts are about 80 percent fat), it's unsaturated fat, which is considered heart-healthy because it's thought to lower your overall cholesterol.

Nuts also contain fiber, Omega-3 fatty acids (the anti-inflammatory kind also found in fish) and vitamin E, which is good for your heart and your skin. Nuts contain powerful elements like L-arginine which some take to improve circulation and erectile dysfunction, and plant sterols, which are added to foods like orange juice to make them heart-healthier. Basically, nuts are superfoods.

Cashews grow on an "apple." One pound of cashews requires 180 gallons of water. Getty Images

The only downside to nuts is that they can be little calorie bombs. The American Heart Association recommends eating only four servings of unsalted nuts a week. It's also recommended to eat raw or dry-roasted nuts, not the oily, greasy or sugary ones. And note that a serving is a small handful (1.5 ounces) of whole nuts or 2 tablespoons of nut butter.

For the best choices when it comes to maximizing the protein content in your nut choice, we went to the USDA to find out which nuts pack the biggest protein punch.