Meat is a great source of high-quality protein that no single vegetarian food can provide. A 3-ounce serving of lean beef offers the most protein with the fewest calories when compared to plant proteins such as peanut butter, black beans and tofu.
A 3-ounce serving of lean beef is about 180 calories. You would have to eat 670 calories of peanut butter (more than 7 tablespoons) to get the same amount of protein.
A person would need to consume two to three times the calories provided in a 3-ounce serving of beef to get an equivalent amount of protein from a veggie burger.
The USDA has approved 29 cuts of lean beef. All lean beef cuts have less than 10 grams of total fat, 4.5 grams or less of saturated fat and less than 95 milligrams of cholesterol per 3½-oz serving.