Warning Issued Over Weight Loss Jabs

Newsweek ^ | Jan 08, 2026 | Jordan King

[nickcarraway]

People who stop taking weight-loss injections such as Wegovy and Mounjaro regain pounds much faster than those who halt exercising and dieting, a new medical study shows.

Research published in The British Medical Journal this month suggests that people lose around a fifth of their body weight when taking the jabs. But once they quit them, they regain 0.8 kg per month on average, meaning they return to their pre-treatment weight in around a year-and-a-half, according to the findings.

The study was based on the analysis of more than 9,000 adults worldwide taking weight management medications (WMMs).

Novo Nordisk, the parent company of Wegovy, told Newsweek that this study "highlights the chronic nature of obesity and suggest that ongoing treatment is necessary."

Eli Lilly and Company, the parent company of Mounjaro, told Newsweek: "When treatment is stopped, weight can return, which reflects the biology of the condition rather than a lack of effort."

Newsweek reached out to the Centers for Disease Control and Prevention (CDC) via email for comment.

The findings come as usage of weight-loss jabs surges in the United States — a Rand Corporation survey from last August found that nearly 12 percent of Americans had used glucagon-like peptide (GLP-1) drugs, including Wegovy and Mounjaro, for weight loss.

The findings also suggest that users need to take the drugs long-term for continued effect, which could have a large financial impact on them.

What To Know

The study, published in The BMJ on January 7, summarized evidence from 37 trials involving 9,341 participants, most of whom received newer "incretin mimetic" drugs such as semaglutide (Wegovy) or tirzepatide (Mounjaro).

The key findings included:

After stopping WMMs, adults regained an average of 0.4 kg (0.9 lb) per month; for newer drugs,

[Williams]

Everything you said was accurate, except for the stomach shrinking part, although it may feel like your stomach is smaller, and it may shrink off you eat less.

[Some Fat Guy in L.A.]

I take Ozempic (for Type II diabetes, not weight loss). I’ve had to skip 2 doses to prep for some surgery and boy am I hungry now. People who take the larger weight loss dose probably experience that even worse when they stop.

[suasponte137]

Lol..what movies is that from?

IT looks like my type of comedy, but i dont recognize it.

[dfwgator]

The Jerk.

[OrangeHoof]

Here’s what Google says about how Mounjaro works:

Increasing Insulin Secretion: Mounjaro stimulates the pancreas to release more insulin when blood sugar levels are high (after eating), which helps move glucose from the bloodstream into the body’s cells for energy.

Decreasing Glucagon Production: It lowers the amount of glucagon (a hormone that tells the liver to produce and release stored sugar) made by the liver, preventing excess glucose from entering the bloodstream.

Slowing Digestion: The medication slows gastric emptying (how quickly food leaves the stomach), which makes you feel fuller for longer periods and helps prevent sharp blood sugar spikes after meals.

Reducing Appetite and Cravings: It acts on appetite centers in the brain (the hypothalamus) to decrease hunger, reduce cravings, and help manage food intake, contributing to a calorie deficit.

Improving Insulin Sensitivity: Over time, it helps your body become more responsive to its own insulin, which is beneficial for managing type 2 diabetes and reducing fat storage, particularly visceral belly fat.

---

And if the word “shrinks” offends you, I think it does to some extent because eating less is one of the goals and since the stomach expands as you overeat, it should naturally shrink as you eat less.