One of the most common questions pre-op patients have prior to bariatric surgery is what their weight loss surgery diet will be like post-op. Odds are, you’ve heard or read all sorts of information specific to the procedure you’re considering, whether it’s a Lap-Band, gastric bypass, gastric sleeve or other form of weight loss surgery. Everyone talks about “taking care of your pouch” and tricks to sneak in sufficient nutrients. Although your doctor will be your best source of advice, here is a quick overview of what to eat after weight loss surgery.
Use the Tools
The shiniest, most practical hammer in the world cannot build a beautiful home without a dedicated carpenter. In the same way, while weight loss surgery is an amazing tool, the surgery alone will not produce dramatic results. You must be willing to commit to a new way of eating. Not surprisingly, the foods you choose will be different, as will the portion sizes. But, the new way of eating may also require you to eat at different meal times or focus more on nutritional intake than you did before surgery.
Many patients find that the first weeks following weight loss surgery are the easiest. For psychological and physical reasons, they are less inclined to want to indulge in large meal. Which is good, because you will first be put on a liquid diet, then a pureed diet. This gives your stomach time to recover from the surgery — regardless of the procedure — while providing necessary nutrition. Generally, after 4 to 6 weeks, you can begin your “normal,” post operative diet.
The diet isn’t difficult, but it is dramatically different from what most patients are used to eating prior to surgery.
Wonderful Simplicity
Although the details will vary depending on the type of surgery you have, there are really only four rules concerning what to eat after weight loss surgery.
1. Avoid High Fat Foods and Sugar. Obviously, the goal is to lose weight — so why would you continue to consume high-calorie foods? With the Lap-Band and gastric sleeve, saying no to sweet treats takes some willpower. With gastric bypass surgery, your body just plain won’t let you indulge. Eating fried foods or foods with a high sugar content can result in “dumping” syndrome. Symptoms include sweating, nausea, vomiting and diarrhea, often within minutes of consuming anything high in fat or sugar.
2. Eat Small Portions. Meal and snack sizes post surgery are usually about three bites. But don’t worry about feeling hungry, because your stomach will be reduced from about the size of two fists to a small pouch that is “full” with only a few ounces of food. Regularly eating more than a few bites can “stretch” the pouch over time, and undo the results of the surgery. So, listen to your body’s cues for when you feel full, and don’t push it.
3. Chew Food Thoroughly. Food should be chewed to a consistency of puree, or applesauce. This can help your body absorb as much nutrition as possible, especially if you have had a gastric bypass procedure. Prior to surgery, your full-size stomach had “churning” capacity, which helped break down the foods you ate into a kind of paste the body could use. Once the stomach is reduced to a small pouch, you have to make sure the food is as close to that state as possible before swallowing. At first, you may even want to “go overboard” by chewing each bite 20 times, just to be very conscious of the process.
4. Drink Lots of Water, But Not with Meals. Drinking 8-10 glasses of water each day will help you feel full between meals and keep your body hydrated. However, you should sip all liquids throughout the day, and not drink anything for 30 minutes before and after meals or snacks. Drinking a beverage during a meal has two negative effects. First, you might be washing down more food than you should eat, overriding the function of your new, smaller stomach pouch. And second, water and other liquids can take up valuable space needed for nutrition, making you feel full before you have eaten enough to get the vitamins and minerals you needed for energy, strength and health.
Your doctor will give you specific instructions for your weight loss surgery diet, and heading your surgeon’s advice can ensure that you achieve and maintain a healthy weight. But, if you’re ever in a pickle, these four guidelines can help you get the maximum results from weight loss surgery.


