Bariatric surgery is designed to give obese and overweight patients a better chance of achieving significant and long-lasting weight loss when diet and exercise have failed. There are several variations of this procedure that work by physically restricting food intake, limiting the body’s ability to absorb nutrients or both. Ideally, this surgery is used as a weight-loss tool along with a major lifestyle shift toward more conscious and healthy eating habits.

How Much Does a Bariatric Surgery Candidate Weigh?

The weight limit for this surgery is based on the BMI (body mass index) table. This tool estimates a person’s amount of body fat in comparison to bone and other tissues. A BMI of 40 or more is considered morbidly obese. Morbid obesity may qualify a patient for this procedure even if they are otherwise in good health. Patients with a BMI as low as 35 may be considered for the surgery if they have one or more serious health conditions that tend to occur at a higher body weight. The LAP-BAND® (a form of gastric banding surgery) has also been approved since 2011 for patients with a BMI as low as 30 if a patient also has a weight-related medical condition.

To give you an idea of what these weight requirements cover, here is an example of BMI numbers and approximate weight in pounds for an individual who is 5’6” tall:

BMI of 40 = 245 pounds
BMI of 35 = 215 pounds
BMI of 30 = 185 pounds

What Health Issues May Accompany a High BMI?

Here are some of the problems that an overweight or obese patient may experience that could make them a candidate for bariatric surgery:

  • Type 2 diabetes (type 1 diabetes is not necessarily improved by weight loss)
  • Hypertension (high blood pressure – including intracranial pressure that can mimic a brain tumor)
  • Sleep disorders and breathing problems – obstructive sleep apnea and shallow breathing (obesity hypoventilation syndrome)
  • High cholesterol or potential for early development of coronary heart disease based on family history
  • Arthritis (or weight-related joint pain)

Obese patients may also experience significant quality of life challenges such as:

  • Limited mobility including difficulty exercising or even walking
  • Embarrassment over personal appearance leading to social withdrawal
  • Difficulty finding employment (due to cultural stigmatization of obesity)
  • Tension in relationships with family and significant others over inability to lose weight

Being able to lose weight and keep it off may provide relief from some of these issues. However, it is important that the patient be determined to have the surgery for their own benefit and not to please others. The aftermath of this operation can actually put more strain on relationships; so it is important for family members to be supportive of the decision.

Weight Loss Prior to Bariatric Surgery

Obviously, patients who seek weight-loss surgery are not expected to reach and maintain a healthy body weight prior to the procedure. That would make the operation unnecessary. However, they do need to demonstrate that they have tried less invasive approaches to weight loss. A typical candidate has been obese for many years after multiple weight loss attempts. They may have tried some or all of the following:

  • Calorie restriction
  • Carb restriction
  • Physician-supervised weight loss (with fasting and/or nutritional shakes)
  • Prescription diet pills
  • Over-the-counter weight-loss supplements
  • Daily cardiovascular exercise to burn fat
  • Food journaling to track and manage food intake
  • One-on-one and group counseling regarding diet and exercise
  • Behavioral modification (such as therapy or hypnosis to deal with overeating habits)

Candidates for surgery may have experienced ongoing difficulty losing weight, keeping it off or both. A history of yo-yoing weight (that goes up and down) is common. Patients who are overweight or moderately obese may undergo the surgery without another weight loss attempt; or they may be advised to try one more time before committing to the surgery. Starting out at the lowest possible weight may make the surgery, recovery and subsequent weight loss easier. Patients who are extremely obese may be required to lose some weight prior to surgery to reduce risks associated with the operation.

Other Factors Affecting Who Can Get Bariatric Surgery

Most patients who undergo this surgery are between the ages of 20 and 60. Other than weight-related health conditions, they should be free of major medical problems that could impact the outcome of the procedure. These include:

  • Blood clots
  • Liver disease
  • Kidney stones
  • Heart disorders
  • Advanced organ disease (heart, lungs, liver)
  • Substance abuse (including excessive use of alcohol)
  • Smoking
  • Diseases impacting the GI tract (esophagitis, IBS, Crohn’s, etc.)
  • Allergy or other risk factor for general anesthesia
  • Autoimmune disease such as lupus that affect connective tissues
  • Long-term use of steroids or other medications that suppress the immune system

Mental and emotional wellbeing are also very important factors affecting whether a patient is a good candidate for weight-loss surgery. The post-surgery lifestyle is very demanding and involves strict adherence to diet and exercise recommendations. Patients who don’t have the time, ability or motivation to engage in appropriate self-care are at high risk for experiencing ongoing complications from this operation. There are a number of mental health and behavioral issues that can make dealing with weight-loss surgery too overwhelming. These may include:

  • Binge eating or bulimia
  • Depression or anxiety
  • Unresolved trauma from childhood abuse

These challenges should be addressed and treated/controlled prior to surgery.

The Ideal Candidate for Bariatric Surgery:

  • Accepts the risks of the surgery after being fully informed
  • Understands the ongoing side effects that may result from the procedure
  • Has realistic expectations regarding how much weight they may lose, and how fast this may occur
  • Is prepared to deal with unwanted aesthetic body changes such as drooping, excess skin
  • Is strongly motivated to adhere to all post-procedure lifestyle instructions including diet, exercise, supplementation, nutritional counseling and medical followup for the rest of their life