Top gastroenterologists gave a glowing review of new weight loss drugs, and ranked them in order of effectiveness

• New medical guidelines have been published that strongly recommend certain weight loss drugs.
• The researchers ranked the drugs, with semaglutide (aka Wegovy) coming out top.

The American Gastroenterological Association has for the first time released medical guidelines that strongly recommend prescribing weight loss drugs to certain patients and rank their efficacy.

The guidelines were drawn up by a team of experts including clinicians with expertise in obesity medicine, gastroenterologists, and a registered dietitian specializing in obesity.

The researchers assessed eight weight loss drugs, including semaglutide and liraglutide, with the aim of helping doctors decide which to prescribe to patients, and found that there are multiple effective and safe treatment options available.

They said they "strongly recommend" the use of weight loss drugs in addition to lifestyle changes for people with obesity and overweight who have been unable to lose weight through diet and exercise alone.

The drugs are effective alongside lifestyle changes

Using data from existing studies, the researchers assessed the drugs for positive and negative impacts, with the main focus being total body weight lost. They also compared the amount of weight lost by patients who took the drugs and those who only made lifestyle changes.

Lifestyle interventions generally included eating in calorie deficits of around 500-600 per day, plus 150 minutes of physical activity per week.

Weight loss was "substantially higher" when people took one of the drugs as well, researchers found.

They recommended four medications as first-line options for weight loss alongside diet and exercise.

The weight loss drugs in order of efficacy:

These drugs led to moderate or large amounts of weight loss and caused small or not-substantial negative side effects, the researchers wrote in the guidelines.

When combined with lifestyle changes, each of the drugs is likely to lead to a high proportion of patients losing five to 10% of their total body weight, which could have a significant positive effect on long-term health, they said.

Semaglutide, which helps regulate blood sugar levels, led to the greatest percentage of weight loss in studies when compared to other drugs, according to the guidelines.

Initially developed to treat type 2 diabetes, semaglutide was approved for weight loss in 2021 and become so popular that shortages were announced by the manufacturer, Insider's Gabby Landsverk reported. It can be taken orally or by injection, and works by curbing appetite.

Semaglutide has also led some people to crave alcohol less, as Insider's Anna Miller reported.

One of the drugs assessed by the team, orlistat, was not recommended because it led to small amounts of weight loss and the side effects meant many people stopped using it.

"These medications treat a biological disease, not a lifestyle problem. Obesity is a disease that often does not respond to lifestyle interventions alone in the long-term," Dr. Eduardo Grunvald of the University of California San Diego, who co-authored the guidelines, said in a press release.

The drugs have the potential to improve many aspects of a person's health, a co-author of the guidelines said

Perica Davitkov, senior methodologist of the guidelines and co-chair of the team, told Insider that he believes the drugs are an exciting development and he was surprised at their efficacy, but their role in weight loss maintenance remains to be seen.

"They work really well," Davitkov said. "It's significant weight loss when added to lifestyle change."

The drugs have the potential to improve people's obesity-related health problems, such as non-alcoholic fatty-liver disease, diabetes, hypertension, and joint issues, Davitkov said.

"Not only losing weight, it's just improving people's health," he said.