Could new weight-loss drugs make dieting redundant?
Emma was at the point of trying anything. She was 49, and 98kg. Her weight had been rising for years. She couldn’t run any more – an activity she’d enjoyed – and her joints were painful. Her doctor had told her she was prediabetic.
Emma (not her real name) is an Auckland-based marketing manager and says she has a healthy relationship with her body, but she also feels the societal pressure of being a larger woman.
“It’s okay to be older if you are slimmer,” she says.
She has noticed this particularly in a work context. “I think if you are an older, overweight woman, you’re just throwing up another hurdle, another barrier in front of yourself. From a business and career perspective, [I feel] I need to be smaller, because my perception is that being an older, overweight woman with grey hair is just too many marks against you.”
Emma has worked hard on her health, and on weight loss. “I exercise. I go to the gym four days a week. I don’t drink lots. I don’t smoke. I don’t eat crappy foods,” she stresses. Even after seeking the help of a dietitian, she lost just 2kg in 12 weeks. “The dietitian said, ‘You’re doing everything right.’ I don’t know what to do next.”
What Emma did next was talk to her doctor about medications. And that led her to the new frontier in weight loss: GLP-1 agonists. More commonly recognised by their brand names such as Ozempic, Wegovy and Saxenda, these are the blockbuster drugs made famous by such celebrities as Oprah Winfrey and Elon Musk. They’re the reason many in Hollywood have apparently shrunk their already-small bodies dramatically.
This new class of drugs was first released in 2005 for the control of type 2 diabetes. For that condition, they offered an “absolute game changer”, according to endocrinologist and diabetes specialist Jeremy Krebs, a professor at the University of Otago, Wellington, and part of the Edgar Diabetes and Obesity Research Centre. Krebs and his colleagues were involved in some of the early trials of GLP-1 agonists for diabetes.
“I’ve been around a bit too long now,” he says with a smile, “and I’ve seen four or five new classes of drugs come in over the course of my practising time in diabetes. And I think the GLP-1 agonists are probably the most important additional drug class in the armoury of managing diabetes and obesity that I’ve seen.”
As people with diabetes using GLP-1 agonists started to experience weight loss alongside other better health outcomes, versions of the drugs were quickly developed and released under different brand names to treat obesity on its own. The doses needed for weight loss are generally larger than what’s used for diabetes.
GLP-1 agonists work by boosting the action of a gut hormone called glucagon-like peptide-1 (GLP-1). The lower small intestine produces this peptide after eating, when it stimulates insulin release. It also reduces the counter hormone to insulin, glucagon.