According to the CDC, in 2015-2016, 93.3 million US adults (that’s roughly 40% of the US population) was considered obese (BMI of 30 or more). Because of the tremendous health issues and costs associated with obesity, the field of bariatrics has grown immensely. The American Society of Metabolic and Bariatric Surgery (ASMBS) is the main governing body and serves as a major resource for practicing physicians in the US. In an effort to combat the obesity epidemic of obesity, various medical and surgical options have evolved. At this time, bariatric surgery has been shown to be the most effective and durable treatment for morbid obesity.1 Surgery results in significant weight loss and helps prevent, improve or resolve more than 40 obesity-related diseases or conditions including Type 2 diabetes, heart disease, Obstructive sleep apnea and certain cancers.1 According to the ASMBS database, 228,000 bariatric procedures were performed in the US (this includes the sleeve, gastric bypass, duodenal switch, and revision surgeries). Unfortunately, this accounts for maybe 1% of the patient population that qualifies for surgery.
For those who do choose to undergo surgery, we have encouraging short term and long term data. We know that patients will generally reach their predicted weight loss from surgery within the first 12-18 months of surgery. And, as a general rule of thumb, the more aggressive the surgery, the more weight you will lose and keep off. In 2018, ASMBS performed a review of all available studies on the medium and long term durability of bariatric surgery.2 The study showed the following:
| Prodedure | 1 yr Excess Body Weight Loss | 10-20 yr Excess Body Weight Loss |
| Laparoscopic Sleeve | 75% | 55-60% |
| Laparoscopic Duodenal Switch | 85% | 80% |
As a bariatric surgeon, it not uncommon for my patients to experience weight loss plateaus and some weight regain after the 18 month mark (and sometimes sooner). It is important that I first explain that these things can occur and are not an indication of complete failure on part of the patient or surgery! After surgery, we always need to be looking ahead at the long game to ensure that all of your work as a patient is not lost. A study in 2005 in the American Journal of Clinical Nutrition showed that “successful losers” exhibited the following traits: 3
High levels of exercise (almost an hour a day)
Low calorie – low fat diet
Regularly eating breakfast
Consistent eating pattern on the weekdays and weekends
Self-monitor and kept food logs
Decreasing the effects of metabolic adaption
This study correlates well with what I have observed in my own clinic. Patients need to recognize that weight maintenance is lifelong and does not stop once you have met your goal weight. My most successful patients certainly have incorporated some, if not all, of the above mentioned traits. Exercise, keeping food logs, and having consistent eating patterns are key. But what exactly is the last point referring to….metabolic adaption? And how can it hinder weight loss?
As you lose weight, you have reduced energy needs. This is called metabolic adaptation. When we were cavemen, our bodies adapted to our changing diets. When we were able to eat plentiful, we grew stronger muscles and stored excess fat. However, in times of famine / lack of food, our bodies adapted by slowing our metabolism through a variety of digestive and hormonal pathways. This allowed our bodies to survive on LESS CALORIES. This same situation occurs when we diet or undergo weight loss surgery. We are causing our bodies to enter into a calorie or ENERGY DEFICIT. It is this prolonged energy deficit that causes our bodies to WANT TO REGAIN OUR FORMER WEIGHT through altered metabolic pathways! There are several studies that have looked at what we can do to decrease or halt the effects of metabolic adaption.
