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The Importance of Nutrition Before Bariatric Surgery

The Importance of Nutrition Before Bariatric Surgery

Dec 29, 2021

Before taking the leap to life-changing bariatric surgery, you may first have to prepare your body and your mind. You’re about to embark on a life and body transformation where you’ll need to completely change the way you think about food in order to reap the full benefits.

There are a number of reasons to change your diet before surgery. The first is safety. “A closely-monitored, low-calorie diet will help to reduce the size of your liver and the amount of fat around your stomach to lower the chance of complications during surgery,” said Keith Kreitz, M.D., bariatric surgeon and medical director of bariatric surgery at Inspira Medical Center Mullica Hill. 

As a candidate for bariatric surgery, you are likely storing extra glycogen in your liver, which may be larger than normal. Eating a low-calorie diet will reduce glycogen stores and fatty deposits and shrink the size of your liver. This will make it easier to safely move your liver aside during surgery. 

Changing your diet prior to surgery will also preserve and protect muscle tissue. Your new diet, both in the weeks leading up to surgery and after surgery, will be low-calorie, low-fat, low-carbohydrate and high-protein. 

“Depending on the type of procedure you’re having, your stomach may be greatly reduced in size, and the way food and nutrients are absorbed may change—especially protein,” said Kreitz. “Eating at least 60-80 grams of protein each day will help your body to burn fat on your low-calorie diet, rather than muscle tissue.”

Your dietitian will also recommend a series of supplements and vitamins to take as part of your new diet, which may include a multivitamin, vitamin D with calcium citrate and biotin. “Adding vitamins and supplements to your diet will provide nutrients you aren’t getting with a low-calorie diet and help to bolster your immune system prior to surgery,” said Bradee Rojas, M.S., R.D.N., bariatric surgery program coordinator at Inspira Medical Center Mullica Hill. “Following your dietitian’s orders about when to take these vitamins and supplements ensures they’re absorbed into the body.”

Finally, it’s vital to change your diet leading up to surgery so you can reach your goals after surgery. “Surgery will help you reach your weight-loss goals, but you have to commit to lifestyle changes, too, and that means a diet that is lower in calories and full of nutrient-rich foods,” said Kreitz. 

In addition to changing your diet, you should focus on changing the way you eat, including:

  • Eating three meals and two snacks per day
  • Eating protein first to ensure your body is getting enough
  • Taking at least 20-30 minutes to eat
  • Chewing food thoroughly, about 30 chews per bite
  • Using small plates and utensils
  • Not drinking anything when you eat
  • Avoiding drinks with calories, except milk and protein shakes

“Making these lifestyle changes can be challenging, but the reward after a successful bariatric surgery is a better life,” said Kreitz. 

To speak with a Bariatric specialist or to request an appointment, visit or call 1-800-INSPIRA

Topics: Bariatric Surgery, Nutrition