It was October 11, 2015. A middle-aged man and a young woman, both severely obese, were struggling with the same feeling. The next day they were going to have an irreversible operation. Were they on the threshold of a new beginning or a terrible mistake?
They were strangers, scheduled for back-to-back bariatric surgery at University of Michigan with the same doctor. He would cut away most of their stomachs and reroute their small intestines. They were almost certain to lose much of their excess weight. But their doctor told them it was unlikely they would ever be thin.
Nearly 2,00,000 Americans have bariatric surgery each year. Yet far more — an estimated 24 million — are heavy enough to qualify for the operation, and many of them are struggling with whether to have such a radical treatment, the only one that leads to lasting weight loss for virtually everyone who has it.
Most people believe that the operation simply forces people to eat less by making their stomachs smaller, but scientists have discovered that it causes profound changes in patients’ physiology, altering the activity of thousands of genes in the human body as well as the complex hormonal signalling from the gut to the brain. It often leads to changes in the way things taste, making cravings vanish. Those who have the surgery naturally settle at a lower weight.
Over the last year, I followed Keith Oleszkowicz and Jessica Shapiro — a computer programmer and a college student — from their surgeries through the transformations that followed. Jessica, 22, lived with her mother and grandmother in Ann Arbor, Michigan, and worked at Panera Bread preparing food. At 5-foot-3 and 295 pounds, she had a difficult life. She needed a seat belt extender on airplanes.
She had acid reflux and mild sleep apnea. Even worse were struggles of being fat. She never had a date and no man seemed interested in her. She tried programmes like Weight Watchers, but her urge to eat defeated her. Keith was 40, married with a teenage son, and worked as a programmer at an automaker. His older brother had had the surgery, too, 16 years ago, when many doctors were splitting patients open instead of doing surgery laparoscopically. The complication rate was much higher then.
The one-year mortality rate today is 0.1%, safer than gallbladder surgery or joint replacement. Keith, at 5-foot-9 and 377 pounds, was having physical and medical problems: his joints hurt; he could not bend down to tie his shoes; he had sleep apnea; he had high blood pressure.
By the day of their surgeries, Jessica and Keith had spent months preparing. They learned that the gastric bypass operation both had chosen leaves patients unable to absorb some vitamins and minerals. They would need to take supplements daily forever. And because the rearranged digestive tracts can dump sugar into the bloodstream too quickly, they would have to be careful about sugar intake.
The surgeon, Dr Oliver Varban, started by inflating Jessica’s abdomen with carbon dioxide to give him more room to work. Then he made seven small holes in her skin and inserted his equipment, including a cylindrical tube containing a tiny light to illuminate her abdominal cavity, lenses, mirrors and a tiny camera to project the scene on a computer monitor above Jessica’s head. It showed gleaming golden bubbles of fat.
Varban used what looked like a miniature table tennis paddle to push Jessica’s liver aside and give him a clear view of her stomach. It might seem reasonable for Varban to remove some fat from Jessica’s abdomen, but doing that, he said, would result in a bloody, hemorrhaging mess. He said there is a mile of blood vessels in every pound of fat.
Varban cut off most of Jessica’s pink and healthy stomach, leaving a pouch the size of an egg. He stapled and sealed the pouch with a device that looked like a saw-toothed pair of shears, leaving a shiny metallic edge of staples. Then he grabbed the top of her small intestine and attached it to the stomach pouch. Jessica was surprised by the pain. “I was like, ‘What did I do to my body?’ This is not reversible, there is no going back,” she said.
For obesity experts, bariatric surgery is at best a compromise. What they really want is medical treatment with same effect — lowering the body’s set point, the weight it naturally settles into — without drastically altering the person’s digestive tract. Bariatric surgery changes the entire setting of a complex, interlocking system. There is no one place to tweak it. To show what is involved, reports that surgery immediately alters the activity of more than 5,000 of the 22,000 genes in the human body.
“You have to think of it as a whole network of activity,” said Dr Lee Kaplan, obesity researcher at Massachusetts General Hospital. It’s a network that responds to the environment as well as genes, he added. Today’s environment probably pushed that network into a state that increased the set point for many people: Their brains insist on a certain amount of body fat and resist diets meant to bring them to a lower weight.
Intestinal tract
But surgery only alters the intestinal tract. That tells you, Kaplan says, that there are whole classes of signals coming from the gut and going to the brain and that they interact to control hunger, satiety, how quickly calories are burned and how much fat is on the body. For bariatric surgery to work, the setting in the brain that determines how much fat a person will have — what Kaplan refers to as the body’s thermostat for fat — must have been set too high, not broken.
A few rare genetic mutations break the thermostat. People with those mutations have no internal controls on their fat and grow enormously obese. Bariatric surgery has no effect on them. People like Jessica and Keith, whose thermostats were mis-set, reach a point at which they are obese but their weight holds steady without any effort on their part. Surgery can lower their thermostat’s setting.
That simplistic notion — that there may be just a few key places to intervene in the tangled web of controls that sets a person’s weight — seems just that: simplistic. But some nodes of the network may be more important than others. They may be the drivers. “What we need to do is find these mechanisms,” Kaplan said.
A year after his surgery, Keith weighed 284 pounds, down from his starting weight of 377, but not at projected weight of 230. It is increasingly unlikely that he will get there. But he looked and felt transformed. “Some people I haven’t seen in years don’t recognise me,” he said.
Jessica lost 112 pounds, about what was predicted. She began classes at Eastern Michigan University in the fall but dropped out in October, as she did not like the courses and had lot of anxiety. Before operation, she could blame her stalled life on obesity. Now, she says, “I don’t have an excuse.” She wants to lose 40 pounds more. Although she has mixed feelings about the surgery results and though she is disappointed her life hasn’t changed as much as she hoped, she said she doesn’t regret having the operation.