Your body doesn’t like to lose weight.
“Our bodies are evolutionarily built to survive famine,” said Dr. Sue Pedersen, an endocrinologist and obesity medicine specialist.
As you shed pounds, you start making more hormones that induce hunger, and fewer hormones that suppress it, she said. For many, energy burn decreases, too.
“All of that promotes us to feel very hungry and want to go out and find food and have more cravings,” Pedersen continued, “because our body wants us to survive the famine.”
But what if you could get a little help fighting those cravings?
That’s the idea behind an approach being advocated by some doctors to treat obesity: using interventions that target not just what’s on your plate, but what’s in your brain.
Diets
Lifestyle interventions, like diet and exercise, are the “cornerstone” of obesity treatment, Pedersen said.
“Nothing works without that.”
The only way to keep weight off is to consume fewer calories, agrees Dr. Sean Wharton, an internal medicine specialist who focuses on obesity and diabetes. But that’s not everything.
“It’s never about the diet. It’s about maintaining the diet.”
“It doesn’t matter what diet it is: ketogenic, intermittent fasting, wheat belly, fibre based, whatever. Doesn’t matter,” Wharton said.
“What matters is, can you maintain it in the face of significant hunger due to the changes in the brain neurochemistry?”
Not a lot of people can maintain weight loss — only about 10 per cent of people with obesity, according to a recent Obesity Canada survey. Other studies, too, suggest that weight regain is common.
Canadian clinical practice guidelines, published in 2006, state: “Lifestyle interventions remain the cornerstone of the treatment of obesity, but adherence is poor and long-term success is modest because of significant barriers both on the part of affected individuals and health care professionals responsible for the treatment.”
Pedersen notes that dietary guidance needs to be tailored to an individual’s needs: one diet won’t work for everyone.
But other things can improve a patient’s chances of success.
Surgery
Bariatric surgery is the “gold standard” treatment for people with a significantly elevated body mass index, Wharton said.
And it doesn’t work the way you might think. While surgery alters the digestive system, one of its biggest effects is on hormone production, Wharton said.
“By rewiring the GI tract, it releases hormones that go from the gut up to the brain to tell the brain that the weight loss that is occurring is not problematic,” he said.
Combining surgery with lifestyle changes increases the chance of success, he said.
“It’s now much easier to keep those lifestyle options.”
With that said, many patients aren’t interested getting an invasive surgery, with all the risks that entails, Pedersen said.
Medication
A less-invasive option is pharmacotherapy, or medication.
There are currently three drugs approved in Canada for weight management, with others currently being researched. One of the approved medications, orlistat, acts on the digestive system, changing how people absorb fats from their diet.
A second drug, liraglutide, imitates the hormone GLP-1, which helps tell our brain that we feel full. Some people with obesity have an imbalance in their production of this hormone, and taking the drug can help to correct this, Wharton said.
The third drug, Contrave, is a combination of two medications: naltrexone and bupropion. “It’s not a hormonal treatment, but it does target those same areas in the brain, which tell us that we feel full and also have an effect to change food cravings,” Pedersen said.
Contrave and liraglutide both work to correct problems with the brain’s neurochemistry, Wharton said, and support people as they make lifestyle changes. Patients taking drugs for weight management see greater success than with lifestyle changes alone, according to a review Wharton co-authored in 2017.
“You now have a chance. It’s now possible to maintain it.”
However, few insurance plans in Canada currently cover medication for obesity, Pedersen said.
Therapy
Another technique to help with weight loss efforts is an old psychological standby: cognitive behavioural therapy. Wharton believes that by setting clear motivations for treating your obesity, and talking through these and coping strategies with a therapist, you can help improve your chances of success.
Every person’s case is unique, Pedersen said, and just telling them to “eat less and move more” without specifically addressing their own unique circumstances isn’t likely to work.
Some people are on medications that promote weight gain, she said, or have a distorted sense of portion sizes, or have a specific emotional relationship to food.
“The list goes on,” Pedersen said. “There’s about 20 different things that we look at in each individual person.”
In the future, Pedersen said, obesity treatment will take a “precision medicine” approach.
“I think the closest thing is probably to profile their hormones, and then saying you need some of this one and some of that one, and then you would have all of these hormone choices as prescribed medication.”
Wharton is also a believer in the future of drugs to help with obesity treatment.
“I believe that in the next 10 to 20 years, pharmacotherapy will be the primary treatment for elevated weight,” she said.