This weekend, as Nutrition 2025 opens, four diverse professional groups announced a noteworthy collaboration. These groups came together to publish a clinical advisory on nutrition priorities that support GLP-1 therapy for obesity. The groups are the American College of Lifestyle Medicine (ACLM), the American Society for Nutrition (ASN), the Obesity Medicine Association (OMA), and the Obesity Society (TOS). It’s noteworthy because the groups each bring distinct and different biases to the subject of lifestyle therapy for obesity: Is it critical, helpful, or optional with GLP-1s?

And yet, they found common ground.

Evidence and Reason

To start, we will state the obvious. Strictly speaking, this is not evidence-based guidance. Lawrence Cheskin, a George Mason Distinguished University Professor and obesity medicine physician, told us:

“I generally find these recommendations to be very well thought-out and rigorously referenced.

“That being said, the references themselves that are cited, especially those that refer to dietary recommendations and the like related to GLP-1s (and their side effects), contain a plethora of merely ‘common-sense’ statements, rather than experimentally verified facts.

“I spent all day in my clinic at Johns Hopkins yesterday dealing with a number of patients on, or starting GLP-1s, and made a variety of similarly non-evidence-based suggestions. Until there are well-controlled studies to guide more precisely what we recommend, this area, like so many in medicine, will have to await more data to become truly evidence-based.”

We will paraphrase from Mike Tyson. Everyone has an evidence-based plan until they come face to face with real people living with obesity. Then we make real choices to help people.

Is Diet and Exercise Dead?

There can be no doubt that the role of diet and exercise in obesity care is changing. The advent of new and highly effective obesity medicines makes it so. But for people who are taking GLP-1s, lifestyle therapy is not dead, as some have suggested. Rather, it is taking on new life in a different form with a different purpose. It may well be evolving into a supportive or adjunct role where it used to be primary. Time will tell.

This new consensus paper, while not perfect, is a respectable attempt to describe this evolving role.

Click here for the new guidance, here for a commentary that goes with it, and here for perspective from the Obesity Society. For further perspective, click here and here.

Breakfast Table with Blackberry Pie, painting by Willem Claeszoon Heda / Wikipedia