More than 40% of American's are obese, according to the Centers for Disease Control and Prevention (CDC). And the epidemic isn't slowing down, resulting in millions of people suffering from health conditions that may be associated with obesity such as asthma, heart disease, stroke, type 2 diabetes, some cancers, and sleep apnea.
Jonathan Carter , MD, has helped patients lose weight for over a decade, as part of the UCSF Bariatric Surgery Center . His team has performed more than 3,500 weight-loss procedures since it started in 1998. Surgeries are safer, with more than 99% of patients treated laparoscopically with small incisions using tiny cameras to see internal organs.
We asked Carter how bariatric surgery works and how a new generation of weight-loss drugs is changing some patients' lives.
GLP-1 drugs like Ozempic and Wegovy are all the rage. Why not use them instead of surgery?
We think of obesity on a spectrum. If you need to lose 10 to 20 pounds, a lifestyle intervention is best. If you need to lose 30, 40, 50 pounds and metabolic diseases like diabetes, sleep apnea, hypertension are starting to creep in, that's when changes to diet and exercises are inadequate as a sole intervention, so GLP-1s are also considered. I'm a huge proponent of these medications.
When is surgery best?
Surgery is most appropriate for people with severe obesity; we're talking about patients who are 100- or 150-pounds overweight. For these people, lifestyle modifications and weight-loss drugs aren't enough.
With severe obesity, medications and lifestyle interventions are unlikely to adjust your cardiovascular and cancer risks to normal levels. With surgery, patients can average 30% to 35% of total body weight loss in the first year, versus 15% to 20% for the medications. Bariatric surgery patients get more health benefits upfront. About 50% to 60% of surgery patients with diabetes go into remission. Conditions like hypertension, asthma, liver disease, sleep apnea, incontinence, arthritis may also resolve.
How does bariatric surgery work?
Most patients get gastric sleeve surgery in which 80% of the stomach is removed, leaving a thin banana-shaped tube. Appetite hormones are reduced, and food is delivered to the small intestine faster, causing other hormones to be released that makes us feel full. A few patients opt for gastric bypass, in which a small pouch is created from the top of the stomach, which is then connected to part of the small intestine.
Bypass may lead to slightly greater weight loss, but in the long term the differences are minimal. It is a riskier surgery but may be advisable for patients with severe heartburn, since the sleeve may worsen heartburn in one-third of cases.
Walk me through the process from first appointment to post-surgery.
At UCSF, we consider surgery for those with a body mass index (BMI) of 35 or higher. If they have metabolic diseases, such as hypertension or sleep apnea, we relax the cutoff to 30.
At patients' first surgery appointment, we run labs to monitor medical conditions and an EKG to assess heart health. We have a multidisciplinary practice, so patients meet with a surgeon, nutritionist, psychiatrist, and physician assistant. We ensure that every patient has access to primary care. The surgery takes an hour, patients spend one night in the hospital, and they typically take pain meds for a few days. About 95% sail through; the most common side effect is mild nausea and vomiting.
Not all patients lose as much weight as they'd hoped. What's their next step?
We see maximum effect around 18 to 24 months after surgery, and we may see a gradual mild-to-moderate regain in the years afterwards, say 15 or 20 pounds.
A minority of patients experience significantly less weight loss than we'd hoped. That's where our multidisciplinary approach comes in. Some patients benefit from adding GLP-1medications. But it's also important to look at lifestyle interventions. In bariatric surgery, we've become very successful at suppressing hunger and inducing satiety, but some patients haven't made a change in their behaviors, so our team works with them. Perhaps it's treating sleep apnea, we know that poor sleep contributes to obesity. Perhaps it's assessing their lifestyle: Are they a sweets eater, a nighttime eater, are they eating heavy meals with business clients? We try to address these behaviors before surgery, but many patients need long-term support to help them get back on track.
How do you see the future of weight-loss treatment?
We're seeing the development of new GLP-1s that promise to be easier for patients to take, more powerful, and, hopefully, cheaper. Although we can't rule out long-term risks yet, we might start to see patients get treatment earlier in the disease process, when the BMI just exceeds 30. That would be nipping obesity in the bud before bariatric surgery needs to be considered.
