1. Skip to content
  2. Skip to main menu
  3. Skip to more DW sites
ScienceGlobal issues

Wegovy weight loss: The science and the hype

October 2, 2024

Originally approved to help with excess weight and obesity, the injectable Wegovy and its sibling-product Ozempic, which is for type 2 diabetes, have become synonymous with weight loss fads. Here's what you need to know.

https://p.dw.com/p/4lANZ
An Ozempic injection pen and packaging
The injectables Ozempic and Wegovy, and tablet Rybelsus, are all based on the same drug, and made and marketed by the same company, Novo Nordisk.Image: JOEL SAGET/AFP

It was sometime during the COVID-19 pandemic when Wegovy and Ozempic hit mainstream awareness. Since then, they have taken the weight loss industry by storm.

It's worth noting from the start that while both are based on the same drug or active ingredient — semaglutide — as products, Wegovy and Ozempic were originally intended for different uses.

Ozempic was first approved in 2017 by the US Food and Drug Administration (FDA) as an injectable drug to help "lower blood sugar levels in adults with type 2 diabetes mellitus, in addition to diet and exercise." 

Wegovy was approved the same year to help adults and children aged 12 years and older, who were overweight or living with obesity.

Semaglutide can also be taken as a tablet, marketed with the name Rybelsus.

From tech to television: Celebrities lose weight 

Celebrities, tech moguls and online influencers have championed the drug —  known users include screen stars, musicians and comedians like Oprah Winfrey, Kelly Clarkson and Amy Schumer.

Elon Musk, the public face of X, SpaceX and Tesla, tweetedin October 2022 that he was taking Wegovy when someone asked "What's your secret? You look fit, ripped and healthy."

All this celebrity endorsement for Wegovy and its sibling-products has had a social impact, but also a financial one. What was a drug for a specific medical market has become a phenomenon, visible even on fashion catwalks.  

Novo Nordisk, a Danish pharmaceutical company, manufactures and markets all three versions of the drug. It was valued at $570 (€510) billion in May — bigger than the entire Danish economy, or GDP.

How does the active ingredient semaglutide work?

Semaglutide reduces appetite by imitating a natural hormone called GLP-1.

GLP-1 is released after we eat. It travels to the brain to signal that we are sated. It also goes to the digestive system, where it slows down the process.

Semaglutide decreases blood sugar levels by helping the pancreas make more insulin — this is the mechanism in Ozempic, which treats people with type 2 diabetes, because they cannot produce insulin as their bodies need it.

"Ozempic can also reduce the risk of cardiovascular complications for people with diabetes," said Penny Ward, a physician-doctor at Kings College London, UK.

When used as a weight loss medication, Wegovy is only recommended "as an adjunct to diet and exercise to reduce weight in patients who are very obese," Ward told DW via email.

In clinical trials, most people taking Wegovy lost 5%-15% of their body weight after 68 weeks of weight loss treatment.

But the drug is only recommended for people with a body mass index, or BMI, higher than 30kg/m2, where obesity is deemed a health risk to the individual. 

Wegovy is not recommended for people classed as "overweight" with BMIs between 25.0 and 29.9 kg/m2, or those of a "healthy weight."

Wegovy is not a drug for 'cosmetic reasons'

Ward and other health experts are concerned the drug is being misused as a quick fix for people trying to get slimmer. Ward said Wegovy "is not a drug which should be taken for cosmetic reasons."

Wegovy and Ozempic can cause a range of side effects, including nausea, vomiting, stomach pain, tiredness, or damage to kidney function.

Most symptoms are mild and short-lasting, said Simon Cork, a physiologist at Anglia Ruskin University, UK, but "some serious side effects can occur, such as gallstones and pancreatitis."

There have been anecdotal reports of rarer, more severe side effects, such as bowel obstructions, pregnancy complications, and vision loss.

Cork said that might be due to individuals taking doses "outside clinical boundaries for prescription, either off-license, or through non-legitimate means."

But the side effects mean that semaglutide drugs should "only be taken by very obese patients at risk of major cardiovascular complications and only then under close medical supervision," said Ward.

Model on a fashion catwalk, wearing a t-shirt with the slogan "I (heart) Ozempic"
Health experts are concerned celebrities are promoting Ozempic as a weight loss drug for people who are medically unsuitable to take itImage: Sebastian Reuter/Getty Images

Copycat weight loss drugs on the rise

Weight loss hacks promising quick fixes for slimming have a long history. But they have risen to a whole new level since Ozempic and Wegovy became popular.

The rise in the products' popularity has resulted in  fake versions of Ozempic and Wegovy flooding the online market, as the World Health Organization has warned. 

New supplement cocktails promise "natural" and "side-effect free" alternatives Wegovy and Ozempic as weight loss medications.

The latest to jump on the trend is celebrity business person Kourtney Kardashian. Kardashian launched "GLP-1 Daily" via her supplement brand, Lemme.

Despite the name, however, the supplement does not contain any GLP-1 in natural or synthetic form, and the supplement does not behave like the hormone. The capsule contains food extracts from lemon, saffron, and orange.  

It's marketed as "a breakthrough innovation in metabolic health, formulated to naturally boost your body's GLP-1 production, reduce appetite, and promote healthy weight loss."

But the health experts DW contacted doubted the supplement would work. Cork said he had "not found any convincing evidence." And Ward said claims about the product were based on "hype rather than fact."

"It is helpful to bear in mind that 'brand ambassadors' are often paid for their services in promoting a product," said Ward.

"Many claims are made but none of these have been reviewed or approved by a regulatory authority and the cited studies are of limited quality. There is no discussion of the safety profile, so it isn't possible to know if any side effects were reported," said Ward, who concluded that she would not recommend it to a patient wanting or needing to reduce blood sugar and reduce cardiovascular risk.

Edited by: Zulfikar Abbany 

Sources: 

European Medicines Agency and US Food and Drug Administration product information pages for Wegovy, Ozempic and Rybelsus.

DW journalist Fred Schwaller wears a white T-shirt and jeans.
Fred Schwaller Science writer fascinated by the brain and the mind, and how science influences society@schwallerfred