If you are having a surgery which requires a general anesthetic, the doctor will instruct you to withhold food and water for a set period of time before the surgery. Eating before surgery can be dangerous for a number of reasons, and most doctors prefer to err on the side of caution when it comes to patient safety. Each doctor has slightly different guidelines about surgical preparation, and you should always follow the directions of your doctor to ensure the best care, including directions about eating before surgery, even if they seem excessive to you. Different procedures have different requirements, and a doctor may have an excellent reason for imposing a strict fast on you. It is also important that children follow directions about eating before surgery, even if you need to fast with them to achieve cooperation.

The primary concern about eating before surgery is that general anesthesia causes nausea and vomiting. If the patient vomits while being anesthetized, there is a risk that the vomit could be aspirated into the lungs. This can be extremely dangerous and sometimes fatal if not addressed. During the procedure, vomiting or stomach reactions could also interfere with the anesthesiologist's equipment or the surgical site. Once the patient wakes up, he or she will feel nauseous and will be offered clear liquids and plain foods to help reduce the feeling of sickness.

As a general rule, no solid foods should be eaten less than eight hours before surgery. Patients can drink liquids until four hours before, although they should take small sips, and the liquids should be clear. The guidelines about eating before surgery are different for infants and small children, and you should consult your doctor.

In addition, you should eat lightly, but well, the day before surgery. Avoid heavy meals with lots of fat, as they take a long time to digest. Loading up on pizza the night before a surgery is not a good idea; having steamed fish with vegetables and rice is a much better choice. You should also refrain from chewing or sucking candies before surgery. Studies have also shown that recovery times are greatly reduced if smokers refrain from tobacco use for at least 24 hours before surgery.

Ultimately, the restrictions on eating before surgery are precautionary measures. Obviously, emergency surgery is performed on people who have eaten or drunk before the procedure, and when the choice is between saving a patient's life or waiting, the surgery will go forward. However, for elective or scheduled procedures, eating before surgery should be avoided, since it can lead to complications. If you do end up drinking or eating before surgery for any reason, tell the surgeon, and let the surgical team decide whether or not to perform the procedure.