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Pre-Op Diet for Weight Loss Surgery: Tips for Staying on Track

Bariatric surgery is an option for people who are severely overweight to lose extra pounds and improve associated conditions such as diabetes. However, it’s not an easy way out, and it requires a big lifestyle change, including a permanent commitment to diet and exercise. 

There are several different types of bariatric surgery, but not everyone is eligible for it. 

People who qualify for bariatric surgery have a Body Mass Index (BMI) of 40 or above, or have a BMI of 35 and one of the following conditions: 

  • Diabetes
  • High blood pressure
  • Coronary artery disease
  • Hyperlipidemia (high levels of fat in the blood)
  • Breathing issues during sleep (i.e. sleep apnea or hypoventilation)
  • Osteoarthritis

Set Yourself Up for Success

Once you’ve started the process and gotten approved for bariatric surgery, it’s important to follow a pre-op diet. James Miller, RDN, CD, and Whitney Stevens, RD, CD are registered dieticians who work with bariatric surgery patients at University of Utah Health. According to them, failure to follow the pre-op diet could compromise the surgery.

“Not following the diet can lead to surgical complications or nutrient deficiencies and result in less weight loss,” Miller says. “Following the pre-op diet will optimize your health and prepare the body for the changes it will go through.”

The diet will help you learn to eat smaller portions but will also reduce the size of your liver, which makes the surgery safer and easier for your surgeon. 

“The stomach lies beneath the liver, so by shrinking the liver, it will become more flexible and easier to move during surgery, allowing the surgeon to lift it out of the way and access the stomach,” Stevens says. 

Nourish Your Body

About four weeks before surgery, you will receive a diet plan to follow. The plan typically consists of foods that are high in protein and low in carbohydrates and sugars such as: 

  • Eggs
  • Chicken or turkey
  • Lean ground beef
  • Seafood like salmon, cod, and shrimp
  • Low-fat milk and yogurt
  • Non-starchy vegetables like broccoli, spinach, and green beans
  • Healthy fats like olive oil, nuts, and seeds
  • Fruits

Not only will these foods help with weight loss, but they will help you maintain good energy levels throughout the day, as well as curb cravings for sugary foods. Miller and Stevens recommend eating at least three meals with about three to four hours in between each meal to aid with healthy blood sugar control.

They also encourage logging your food and liquid intake to help with self-awareness of eating habits to ensure you are properly fueling your body.

Stay Hydrated

Miller and Stevens said that hydration prior to bariatric surgery is extremely important because adequate hydration helps with weight loss and maintenance, but it also helps the body to be hydrated during surgery.

“Patients who undergo bariatric surgery are at a higher risk of becoming dehydrated, so adequate hydration before, and especially after, is crucial for healthy weight loss and for quick healing and recovering,” Miller says.

If you’re worried about getting bored with just water, don’t worry—there are other options. Just be sure to cut out alcohol and sugary drinks such as sodas. Besides water, try one of the following to keep your body hydrated:

  • Broth
  • Low-calorie sports drinks
  • Protein shakes

Working with your surgery team, you can follow the diet they provide you. Communicating with them when you have questions or need support will help you achieve your weight loss goals and keep you on track to a healthier a lifestyle.