The question about NPO status before surgery or procedure comes up a lot. NPO or nil per os is a Latin abbreviation for nothing by mouth. Usually there are two circumstances when your doctor will ask you to be NPO. The first circumstance is when you get blood work. So the results are accurate and not falsified by eating. This is especially important when your doctor wants to check for your sugar and cholesterol levels. The second circumstance in which your doctor will ask you to be NPO is usually before a planned procedure or surgery. Having an empty stomach, as unpleasant as it can be, is important to avoid a severe and potentially life threatening condition, which is called aspiration pneumonia. If you have food in your stomach and you’re undergoing surgery or anesthesia, that food can come up through your food pipe and end up in your lungs, causing aspiration pneumonia. In order to avoid this serious side effect, it is prudent that you follow your doctor’s NPO instructions. NPO rules are meant to protect you. So no cheating, please. No gum chewing, hard candy eating, or snacking on a bite of toast.