GLP-1RA Use Warrants Nutritional, Lifestyle Changes: Joint Scientific Statement

Multimodal care must include diet, exercise, and lifestyle modifications in the use of glucagon-like peptide 1 receptor agonists (GLP-1RAs) for obesity management, according to a joint scientific statement from the American College of Lifestyle Medicine, American Society for Nutrition, Obesity Medicine Association, and The Obesity Society published in Obesity.

Background

Randomized clinical trials have reported that GLP-1RAs reduce weight by 5% to 18% among individuals with obesity or overweight and weight-related comorbidities. Among US adults, 6% reported current use of GLP-1RAs in 2024.

In the current guidelines for obesity management by the United States Preventive Services Task Force (USPSTF), recommendations support the referral of adults with obesity to intensive, multicomponent, behavioral interventions comprising diet, physical activity, problem solving, peer support, and relapse prevention components. However, these comprehensive lifestyle modification interventions are not widely used in clinical practice, in part due to lack of sufficient scaling of weight loss programs and a lack of access to services. For example, health coaching has not been approved as a category I Current Procedural Terminology coding by the American Medical Association, which is a barrier for insurance reimbursement.

The statement authors also raised concern about a lack of formal training in medical schools about nutrition and obesity, leading to a paucity of basic knowledge about obesity management in general practice. In addition, clinicians often have limited time with their patients to speak with them about multicomponent obesity interventions. As a result, many patients who are prescribed GLP-1RAs do not receive education about nutrition or other lifestyle considerations during and after GLP-1RA use.

Nutritional and Lifestyle Priorities

Patient-Centered Approach

When prescribing GLP-1RAs, the dose titration and calorie restriction plan should be individualized for each patient on the basis of their unique medical needs and preferences. Clinicians should consider a patient’s social determinants of health (SDOH) to determine potential barriers to accessing their medication or potential nonadherence to lifestyle changes. The Statement authors recommend employing the ‘5A Framework’ to:

• Assess a patient’s status;
• Advise them about the benefits of GLP-1RAs and how nutrition and lifestyle affect outcomes;
• Agree on a care plan that is best-fit for their needs;
• Assist in carrying out the care plan; and,
• Arrange their success through referrals, if necessary.

Baseline Nutritional Screening

Before initiating GLP-1RAs, patients should undergo a nutritional evaluation. This exam should consider medical history, goals for weight reduction, and any comorbidities or conditions that are relevant for GLP-1RA use, such as gastrointestinal (GI) symptoms, eating disorders, and mental health disorders, among others. A comprehensive physical exam that includes a functional status assessment should be performed, and some patients may benefit from muscle mass measurement with bioelectrical impedance or dual-energy X-ray absorptiometry. A dietary history should be taken that assesses current dietary habits, including:

• Vegetable and fruit intake;
• How often they eat fast food or frozen meals;
• Whether they have allergies or intolerances; and,
• Details about previous attempts at weight loss.

Patients should be asked about their behaviors that may affect their weight, such as physical activity, sleep habits, substance use, and how they manage mental stress. The SDOH evaluation should consider whether a patient has access to healthy foods, housing and transportations, and whether they are affected by other health care access barriers.

Management of Adverse Side Effects

As with any medication, GLP-1RAs can cause adverse events, in which nausea, vomiting, constipation, and diarrhea are often reported. Patients should be made aware of these side effects and be advised that they are more common during initiation and dose escalation. Gradual titration of medication dosage or maintenance of the lowest effective dose may mitigate some GI outcomes. Additional mitigation strategies for GI symptoms include eating small meals, maintaining regular fluid intake, consuming foods with lower viscosity, reducing intake of high protein or high fat foods, and avoiding alcohol. If these approaches do not relieve symptoms, antinausea medication, magnesium citrate, or antidiarrheal medication may be considered.

Changes in Dietary Preferences and Intakes

After initiating GLP-1RAs, patients reduce their energy intake by 16% to 39% due to changes in hunger, cravings, and feelings of fullness. These alterations may lead to inadequate intake of nutrients among some patients, whereas others may increase preferences for sugar or refined carbohydrates as a rebound effect. Some patients may require referral to behavioral therapy, changes in dosing, or changes in the GLP-1RA agent if these outcomes are affecting the patient’s quality of life.

As some patients can have inadequate nutrient intake with GLP-1RAs, patients should be educated about prioritizing consumption of a varied diet comprising fruits, vegetables, whole grains, lean proteins, nuts, seeds, and legumes. Small, more frequent meals may be a more effective approach to consuming sufficient nutrients. Clinicians should assess how the patient’s dietary habits have changed at each follow-up visit.

Muscle and Bone Mass Preservation

Coupled with inadequate nutrient consumption, GLP-1RAs may cause reductions in muscle and bone mass among some patients. Muscle and bone mass reduction can lead to physical impairment or disability, increased risk for fracture, reduced quality of life, and increased mortality risk.

The statement authors recommended that individuals on GLP-1RAs should consume the protein content of their meal first to ensure its consumption. However, ensuring protein intake alone is not sufficient to maintain muscle mass, and patients should be advised to engage in regular resistance and strength training. Clinicians should monitor patients for changes in muscle mass and physical function at follow-ups.

Behavioral Change Support

To support the implementation and to maintain the behavioral changes needed to reduce body weight, the statement authors endorsed use of group medical visits (GMVs), registered dietitian nutritionists (RDNs), and Food is Medicine (FIM) interventions.

Compared with usual care, GMVs are associated with improved dietary habits, sleep, patient satisfaction, glycemic control, blood pressure, and weight and reduced health care costs. Similarly, previous research findings suggest associations between RDN-delivered medical nutrition therapy and improved diet quality, body weight, glycemic control, blood pressure, and cholesterol. Additionally, FIM programs have been associated with a reduction in BMI and improvement in nutrition security, diet quality, glucose control, disease self-management, and health care utilization.

Knowledge Gaps

As GLP-1RAs are relatively new in the obesity management space, several gaps in knowledge remain. The statement authors highlighted several areas that require additional research.

The process of natural bodily GLP-1 secretion is not completely understood. It remains unclear how specific dietary or microbiome interventions, dosing of nutrients, and dietary patterns affect endogenous GLP-1 secretion.

Factors affecting GLP-1RA persistence are also poorly understood. Most patients prescribed GLP-1RAs for obesity discontinue treatment within 1 year. After discontinuing GLP-1RAs, many patients regain weight, as adherence to the nutritional and behavioral changes also wanes. Long-term approaches to support GLP-1RA persistence and adherence to lifestyle changes require further research.

The statement authors advocated for review of the diagnostic criteria for clinical obesity. An expert group recently found that using BMI alone to define obesity may misclassify adiposity. This report proposed a new definition of clinical obesity as a chronic, systemic condition that results from excess adiposity and alters tissue and organ function.

The statement authors concluded, “[A]lthough GLP-1[RA]s alone can produce significant weight reduction and related health benefits, several challenges limit its long-term success for individuals and populations. [… A]ll clinicians prescribing GLP-1[RA]s for obesity management should establish a thoughtful plan of care that includes thorough nutritional and lifestyle counseling before, during, and after the weight reduction period. This should include an emphasis on healthful eating, physical activity, and resistance training; screening and management around substance use disorders, eating disorders, mental health, and sleep; and micronutrient or protein supplementation as needed. […] Such comprehensive care will make clinicians more effective stewards of these medications and positive contributors to their patients’ health.”

Disclosure: Multiple study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.