Paris, France: When people stop taking the new generation of weight-loss drugs they pile back on the kilos four times faster than they would after ending diet and exercise regimes, new research found Thursday.
But this was mostly because they lost so much weight in the first place, according to the British researchers who conducted the largest and most up-to-date review of the subject.
A new generation of appetite-suppressing, injectable drugs called GLP-1 agonists have become immensely popular in the last few years, transforming the treatment for obesity and diabetes in many countries.
They have been found to help people lose between 15-20 percent of their body weight.
"This all appears to be a good news story," said Susan Jebb, a public health nutrition scientist at Oxford university and co-author of a new BMJ study.
However, recent data has suggested that "around half of people discontinue these medications within a year," she told a press conference.
This might be because of common side effects such as nausea or the price -- these drugs can cost over $1,000 a month in the US.
So the researchers reviewed 37 studies looking at ceasing different weight-loss drugs, finding that participants regained around 0.4 kilograms a month.
Six of the clinical trials involved semaglutide -- the ingredient used in Novo Nordisk's brands Ozempic and Wegovy -- and tirzepatide used for Eli Lilly's Mounjaro and Zepbound.
While taking these two drugs, the trial participants lost an average of nearly 15 kilograms.
However after stopping the medication, they regained 10 kilograms within a year, which was the longest follow-up period available for these relatively new drugs.
The researchers projected that the participants would return to their original weight in 18 months.
Measurements of heart health, including blood pressure and cholesterol levels, also returned to their original levels after 1.4 years.
People who were instead put on programmes that included diet and exercise -- but not drugs -- lost significantly less weight. However it took an average of four years for them to regain their lost kilos.
This meant that people taking the drugs regained their weight four times faster.
