As if you needed another reason to incorporate more vegetarian foods into your diet, peas and beans have been shown to carry a good source of protein and are more filling than meat. They are also rich in many other nutrients and vitamins.
Based on a research study in Food & Nutrition Research, 43 men of "normal weight" were fed legumes and meat (pork and veal). As it turned out, the beans and peas were more likely to lower hunger and appetite.
Although beans have similar calories to meat, they are richer in water content and in fiber, which is why the legume is so filling. The same is true for peas. This could also be beneficial for weight loss, as you'd feel full a lot sooner eating peas and beans than you would just eating meat. It's best to find your own balance of either meats and vegetables, or just veggies if your diet excludes meat.
Due to legumes making you feel fuller sooner than meats do, a lot of third world countries survive off of meals involving beans and rice. Certain beans and peas are also rich in Vitamin A, Vitamin C, iron, and calcium. Legumes will pack in the magnesium and help those muscles recover after that New Year's workout.