In 2007, approximately 80 percent of the 200,000 weight loss surgeries performed in the United States were gastric bypasses, according to the American Society of Metabolic and Bariatric Surgeons. The procedure helps severely obese patients lose weight by reducing the stomach to the size of an egg and re-routing the digestive system to bypass part of the small intestine. Most surgeons require patients to lose some weight as part of the intensive preparation for surgery.
Bariatric surgeons often require patients to follow a restrictive diet before gastric bypass surgery to help them lose weight. When the surgeon performs the procedure laparoscopically, a minimally invasive approach through small abdominal incisions using a tiny videocamera and special instruments, preoperative weight loss shrinks the liver and permits easier access to the operative site. Losing just 15 pounds reduces the time spent in the operating room as well as the time needed to recover. A review of the records of 881 gastric bypass patients at a large bariatric who underwent a six-month preoperative program between 2002 and 2006 revealed that those who lost at least 10 percent of their excess body weight experienced fewer complications than those who lost less weight preoperatively, according to a December 2009 article published in "Archives of Surgery."
Complying with Insurance Company Mandates
Some health care insurance companies require patients to participate in a medically supervised weight loss program for six months before the company will agree to pay for the operation. A study of 440 bariatric surgery patients between 2006 and 2010 compared the postoperative weight loss success of two groups, both of whom participated in a two-month program of nutritional psychological counseling and a two-week preoperative diet. The 116 patients that participated in a four-month insurance-mandated preoperative program in addition to the standard program were no more successful postoperatively than the patients who participated in the shorter program, according to a 2010 report presented to the American Society for Metabolic and Bariatric Surgeons.
Surgeons' preoperative diet guidelines vary, so follow instructions exactly. Most surgeons limit patients to a liquid diet during the week or two prior to surgery. Some also require patients to begin eating a high protein, low calorie solid diet for up to six months before starting the liquid diet. The specific regimen will depend on your preoperative weight, health condition and health insurance requirements.
Solid Preoperative Diet
A solid food preoperative diet provides plenty of protein while limiting calories and helping you become accustomed to the type of food you will eat after gastric bypass. Planning your meals around lean, high protein meats, poultry, fish, eggs, seafood, low fat dairy foods, tofu, beans and lentils helps to provide fuel and prevent loss of lean muscle. Limit high carbohydrate foods, including bread, fruit, pasta, rice, cereal, crackers and potatoes, to no more than four servings per day. Eat more vegetables and whole grain products and limit or avoid sugary, fatty and fried foods.
Liquid Preoperative Diet
Your surgeon may allow you to drink full liquids -- any food that forms a liquid at room temperature -- for a week or two before switching to clear liquids within 24 to 48 hours of the procedure. Typically, liquids cannot contain sugar, caffeine, alcohol or carbonation. On the full liquid diet, you may have strained soup, skim milk, low fat yogurt and fruit juice, as well as clear liquids. On the clear liquid phase, you may have water, herbal tea, sugar-free popsicles, sugar-free gelatin and broth.