Nitrogen is a chemical that is used to make a variety of antibodies in the human anatomy. As such, foods that are high in nitrogen are recommended for regular consumption. In addition to the benefits to the immune system, foods high in nitrogen are usually converted into carbs rather than fat, which means that they're better for people who are attempting to keep in shape and not put on more fat.
A good measurement for how much nitrogen is in a particular food or food group is how much protein that food has. Protein naturally contains nitrogen, and eating some foods that contain protein at each meal can help reduce a person's overall appetite. Protein also is good for building and rebuilding muscle material, which is something to keep in mind if you are increasing protein intake as part of a diet and exercise routine.
Milk contains a good dosage of both protein, and by association nitrogen. A single glass of milk for instance contains 6.3 grams of protein, whereas a pint of milk contains 19 grams of protein. If you have issues drinking regular milk, soy milk also contains a marked amount of protein, though not as much as real milk does--roughly 6 grams in half a pint.
Fish, which is a good alternative to red meat, is extremely rich in nitrogen and protein. For example, a cod fillet contains 21 grams of protein. Other fish, however, also contain a good helping of necessary nitrogen. Trout, salmon and even fish sticks have healthy amounts of nitrogen as well, but you should vary your diet and shouldn't eat the same types of foods all the time.
Chicken also is a good source of nitrogen rich protein. A roast chicken, for instance, contains 25 grams of protein per every 100 grams of the chicken that's eaten. If you don't prefer full-grown chickens, eggs are also very high in protein. One medium-sized egg, regardless of how it's cooked, contains 6 grams of protein--as much as a full glass of milk, or half a pint of soy milk.
Commonly consumed processed meats and meat products contain a great deal of protein. Sausage for instance contains 12 grams of protein per every 100 grams of meat. Bacon contains 25 grams of protein for the same 100 grams consumed. Even luncheon meat contains 13 grams of protein for every 100 grams of meat. All in all, eating a bologna sandwich or cooking up some sausage might be just the key to getting a little bit of extra protein into a diet, and with it essential nitrogen.