Why diabetic drug Ozempic can help with weight loss — but not for everyone

Nomathemba Chandiwana, 39, has lost about 9kg twice in the past five years. The first time, in 2018, it felt “like I was training for the army”, she remembers of the 4am workouts at the gym, five times a week, for close to six months.

“Yes, I shifted the weight, but it was not sustainable. I couldn’t keep it up. I dropped a dress size [for my sister’s wedding]. But then life goes back to usual [after the big day] and your weight goes up again.”

Then, in 2022 she tried a weight loss drug, semaglutide. She was overweight and lost 9kg over four months — and the weight stayed off.

In some countries, semaglutide is registered as a weight loss drug. But in South Africa, it’s only registered for the treatment of type 2 diabetes, in the form of a weekly injection sold under the brand name Ozempic and made by the drug company Novo Nordisk. Doctors therefore prescribe it “off-label” for weight loss (it’s a relatively commonly accepted practice among doctors worldwide to prescribe medicines “off-label”). 

In fact, Chandiwana is a medical doctor herself. She specialises in helping HIV and obesity patients and works at the Ezintsha research centre. 

She knows about people’s struggle with weight gain. Some of her HIV patients have gained 15kg-20kg on some forms of treatment, and couldn’t shake it. That’s where her interest in obesity medicine started.

Chandiwana has battled with her weight since adolescence. She explains: “That’s the thing with weight: it’s personal. I’m a physician, but I’m also a human being.”

Weighing up the options

Semaglutide is part of a group of medicines called GLP-1 receptor agonists. To your body, it looks like a hormone from your gut that slows down how quickly your stomach empties into the small intestine and tells your brain that you’ve eaten enough. Because you feel full faster and for longer, you eat less.

The medicine was originally developed to help people with type 2 diabetes lower their blood sugar levels by prompting the pancreas to release extra insulin. This, in turn, tells the body’s cells to take up glucose (a type of sugar) and use it for energy. (People with diabetes have too much sugar in their blood because the body doesn’t make enough of the hormone insulin.)

However, when the appetite control effect was noticed, people started using it as a weight loss drug too.

To see if someone qualifies for using a weight loss drug, one of the things doctors look at is body mass index (BMI). 

BMI is a number that tells you how your weight (in kilograms) relates to your height (in metres) and so gives an idea of your risk for becoming overweight or developing obesity, explains Sundeep Ruder, an endocrinologist in private practice in Joburg.

If this number stands at 30 or more, a person is considered obese. At 25 or higher, it’s a sign of someone being heavily overweight. 

“Patients with a BMI of 30, or 27 and with another weight-related condition such as diabetes, high blood pressure or high cholesterol, can be considered for the medicine,” says Ruder. 

But a high BMI alone will not get you on the treatment.

When a doctor is thinking about prescribing the drug, they’d also ask questions about the patient’s mental health, whether they’d be able to afford it (because it can cost over R4,000 a month, depending on the dose someone requires — the dose needed for weight loss is generally higher than what is used to treat diabetes), how motivated the patient is to lose weight and what lifestyle changes they’d have to make to keep up the use, says Ruder. 

“It’s a multifactorial approach and it can be difficult [to see if a patient should go on the drug]. A physician has to be very skilled.” 

“You don’t have to do it alone”

Obesity is a chronic disease and, says Chandiwana, like for other long-term diseases, having medicines to manage it, in addition to eating healthy and exercising, is important.

Yet many people think they simply need willpower to lose weight — and when they relapse after having dropped a few kilograms, they become despondent.

“You’ll never find someone with diabetes or hypertension saying: ‘I can do this by myself.’ It’s the same with obesity management,” she says. 

In a study among people with obesity across 11 countries, researchers found that they wait long — many up to three years — before they go to speak to a health worker about needing help with losing weight. Chandiwana says this may link to stigma around being overweight to a large extent. This means there needs to be a mind shift in how we think about obesity and overweight, she says — much like we had to tackle the stigma around HIV. 

“You have to approach it with compassion and support. And also give someone the tools that they need to deal with a legitimate and complicated chronic disease,” she says.

Getting the right product and dose for you can take a while, and needs to be done with the help of a health worker. There are also side effects to contend with. 

Chandiwana explains that in her case, her doctor started her on a low weekly dose and then gradually upped it every four weeks, until they got to her current dosage of 2.4mg (Ozempic comes in the form of an injection and at this dose someone would need two pens a week).

“I felt tired at the beginning and also had some headaches. The most inconvenient side effects were tummy [gastrointestinal] things. Slight diarrhoea, farting, belching, feeling bloated. But these settle after a while as your body adjusts [to the treatment].”

It’s not about being skinny

Overweight and obesity is a real issue in South Africa. According to the Global Obesity Observatory, four out of 10 women in the country are obese and one in four are overweight. Among men, these numbers come to one in 10 for obesity and one in five for overweight. 

“It’s not about how you look,” says Chandiwana. “It’s about what excess weight does to your health.” Carrying lots of extra weight also leads to other health problems, such as diabetes, high blood pressure and heart disease.

In South Africa, about 15% of people have type 2 diabetes, and almost nine out of 10 cases of this type of diabetes among South Africans can be linked to obesity and being overweight, research has shown.

But how much we weigh has also become a social issue. It’s not surprising then that the scale might tip to the other end, with people wanting to use weight loss drugs when, medically, they don’t need it.

The trend to use Ozempic for weight loss took off on social media in 2022 — not only in South Africa but around the world. The hashtag #Ozempic, for instance, has 300-million views on the social media platform TikTok (South Africa’s fastest-growing social media platform for access to news).

The “unexpected demand” drained stock globally in May 2022, Novo Nordisk told Australia’s medicines regulator. 

South Africa’s stocks dried up three months later, from about August. 

And when people get desperate to get skinny, they might go to extremes, such as buying semaglutide, the main ingredient of drugs like Ozempic, online and mixing their own DIY shots.

Social media buzz and Ozempic stockouts show how desperate people are for a solution to being overweight.

“It’s personal. It’s embarrassing. It’s difficult. [By prescribing weight loss medicine, a doctor can] give people the tools they need to deal with a complicated chronic disease.”

This story was produced by the Bhekisisa Centre for Health Journalism. Sign up for the newsletter.