Bariatric Surgery Pre-Op Guidelines

We’ve put together these bariatric surgery pre-op guidelines to help you prepare to undergo bariatric surgery. We discuss diet and lifestyle changes, the necessary tests to evaluate your health, as well as the dietary changes you will need to make after surgery. 

If you’re considering weight loss surgery, contact the Detroit Weight Loss Center in Southfield, Michigan. Dr. Blake Movitz can help you on your journey toward a healthier you!

What is Bariatric Surgery?

Bariatric surgery (or metabolic surgery) is another name for weight-loss surgery. It includes operations such as gastric bypass or sleeve gastrectomy. The surgeon makes changes to your digestive system to help you reduce your body weight.

Bariatric surgeons, like Dr. Blake Movitz, perform this type of surgery when exercise and diet have not worked or when a serious health concern has arisen because of your weight. The weight-loss procedures can improve your metabolism by impacting your hormones, limiting how much you eat, or reducing how many calories you absorb. 

It’s important to remember that weight-loss surgery is a major procedure that requires significant changes to be made to your digestive system. If you decide to undergo surgery, you must be prepared to make permanent changes to your lifestyle, which includes eating a healthy diet, engaging in regular exercise, getting plenty of restorative sleep, and working on mental health and stress management.

Preparing for Surgery

You will need to make some diet and lifestyle changes before having bariatric surgery. These changes are discussed in detail below.

Pre-Op Diet Changes

Before you undergo bariatric surgery, you will need to make some significant lifestyle changes. Your bariatric surgeon will encourage you to adjust your diet by incorporating lean proteins and complex carbohydrates and avoiding high-calorie foods, such as sweets or junk food.

In the weeks leading up to surgery, you will begin a low-calorie liquid diet. Your diet will include two or more protein shakes each day, along with eight glasses of zero-calorie liquids, such as:


A strict liquid diet will help reduce the size and stiffness of your liver. This decreases the chance of injury to your abdominal organs during the surgery.

You may be asked to drink only clear liquids on the last one or two days before surgery. Then, you will begin an overnight fast the night before surgery.

Pre-Op Lifestyle Changes

You will also need to make some lifestyle changes before undergoing bariatric surgery. These changes may include the following:

  • Participating in an education/lifestyle program: You will undergo preoperative education and nutrition support. You will learn about the surgery and the pre and post-lifestyle adjustments necessary to sustain weight loss.
  • Losing weight: You will likely be advised to lose weight before surgery by restricting your calorie intake and starting a program of exercise and physical activity.
  • Stopping smoking: Smoking affects your ability to recover and can cause complications during surgery. You will need to stop as directed by your surgeon.
  • Avoiding caffeine: You may be asked to avoid caffeine for at least one month before surgery.

Pre-Operative Appointments and Tests

Before you undergo weight-loss surgery, you may need to do some tests to check your general health and determine if you are ready for surgery.

Pre-operative tests may include the following:

  • A complete blood count (CBC)
  • Urinalysis
  • Gallbladder ultrasound
  • Chemistry panel
  • Chest X-ray
  • EKG
  • Vitamin/Micronutrient panel

After Your Weight Loss Surgery

Following your weight loss surgery, you will begin nourishing your body by drinking clear liquids. Gradually, you will move on to pureed foods and then to soft foods, before finally resuming your intake of regular food.

As you resume eating regular kinds of food, your diet will be different from how it was before. The amount of food and drink that you can consume will be limited and you may not be able to eat certain types of food. These adjustments will help you lose weight and maintain your weight loss, in addition to eating more comfortably.

You will also be required to take vitamin and mineral supplements, such as bariatric multivitamins and calcium. If you need help with your post-operative nutrition and exercise, please check out our Coaching Corner.

Your doctor will schedule regular checkups during the first year after surgery, and at least annually thereafter for the rest of your life. Evaluations may include blood work to ensure that you are receiving the right amount of nutrition in your diet.

Schedule a Weight Loss Consultation Today

Contact the Detroit Weight Loss Center in Southfield, MI to see how bariatric surgery can help you. Dr. Movitz offers several treatments, including medical weight loss, sleeve gastrectomy, gastric bypass, and duodenal switch surgery. Book an appointment today to learn more about the right weight loss procedure for you!

Medically reviewed by Dr. Blake Movitz, MD,  FACS

Dr. Blake Movitz

Dr. Blake Movitz

Fellowship trained from the Mayo Clinic in Minimally Invasive Advanced GI Surgery, Complex Endoscopy and Bariatric Surgery.