Reading the labels on the foods that you select is very important to know if the food that you are putting into your body is real food. Real food is not man made but contains natural ingredients. Be sure that you recognize the ingredients as natural ingredients.
One of the common ingredients that is added to processed meats is nitrates. This is common in deli meats, hot dogs, sausages and lots of other processed meats. More than likely any time that you eat that sub sandwich you are eating this preservative.
All vegetables have some natural nitrates in them, especially in celery (celery juice is sometimes used as a natural preservative). What I am talking about is the added sodium nitrate that is added to the meats. This is known is be a carcinogen, especially linked to bowel cancer.
This is not an additive that has to be used and you should be careful in reading the labels to be sure that it is not in the meats that you are purchasing.
Click here to read an article from Dr. Mercola on the dangers of sodium nitrate as a preservative.