Achieving Lasting Weight Loss with GLP-1s: Why Behavior Change Support Matters

Updated on May 26, 2023

As a registered dietitian specializing in post-bariatric nutrition, weight management, and behavior change support, I’ve witnessed people use countless weight loss techniques, diets, and procedures to lose weight. Patients typically don’t have much trouble shedding pounds initially. It’s keeping the weight off that proves challenging. 

Studies show that most people regain more than half of their lost weight within 2 years, and 80% within five years. Even those who undergo bariatric surgery or take weight loss drugs often regain weight post-treatment. Why is it so hard to sustain weight loss, even with invasive surgical procedures and prescription medications?

Obesity, like diabetes, is a complex disease (recognized as such by the American Medical Association in 2013). It’s caused by socioeconomic, behavioral, genetic, environmental, hormonal, emotional, and metabolic factors — many of which we have yet to discover and fully understand. Willpower isn’t the problem.

With over 42% of Americans qualifying as obese and at risk for many comorbidities, I’m thrilled about the potential of new glucagon-like peptide 1 receptor agonists (GLP-1s) to treat the disease. Medications like Ozempic, Wegovy, Mounjaro, and more are shifting the treatment paradigm for obesity, creating more potential benefits for our patients. Yet, these medications don’t come without risks. 

It’s important to note the FDA has only approved anti-obesity GLP-1s when prescribed as adjuncts to a reduced-calorie diet and increased physical activity for chronic weight management. In other words, behavior change is crucial to the success of the drugs. Without appropriate support, people are at risk of developing malnutrition, disordered eating patterns, and regaining weight when treatment is stopped. 

Organizations and healthcare providers offering access to GLP-1s must recognize that it’s absolutely essential to prescribe robust nutritional guidance and behavioral health support alongside weight loss drugs. Care teams of registered dietitians and licensed therapists can help mitigate some of the biggest risks associated with GLP-1s for weight loss:

Weight gain when medication stops

The current research on GLP-1s indicates that weight regain occurs when people stop taking them. Individuals need to establish good habits when beginning their weight loss journey on anti-obesity medications. The medications help curb one’s appetite, but they don’t solve all poor lifestyle behaviors. 

Behavioral interventions for eating, exercise, and sleep are necessary to optimize weight loss sustainability. Registered dietitians and licensed therapists can help people develop healthy eating, exercise, and sleep patterns, and manage self-defeating thoughts. Nutrition behaviors should focus on caloric targets, avoiding overly processed foods and choosing quality over quantity, reducing sugary drinks, planning healthy meals, and eating enough fiber and protein. 

Perhaps most importantly, trained providers teach people how to self-monitor their behaviors in a non-obsessive, healthy way. Food journaling, tracking thoughts, tracking steps, and weighing consistently all set a person up for successful weight management. 

Malnutrition without a balanced diet

It’s a common misconception that people who have obesity are not susceptible to malnutrition — this couldn’t be further from the truth. Malnutrition in obesity shows up as nutrient deficiencies that may be driven in part by high-caloric, low-nutrient-dense food choices. 

Malnutrition is of even graver concern for people taking GLP-1s because the drugs drastically reduce appetite and hunger cues. Eating too little for long periods makes getting needed nutrients for daily metabolic functioning and overall health difficult, especially in patients where vitamin and nutrient deficiencies may already exist. 

Vitamin and nutrient deficiencies can lead to a whole host of other problems, making people more susceptible to developing conditions like osteoporosis, depression, fatigue, poor wound healing, and brittle nails and hair. 

Medical Nutrition Therapy is an evidence-based, individualized nutrition process meant to help treat certain medical conditions that’s provided by registered dietitians, helps prevent malnutrition and manage the uncomfortable side effects of GLP-1s (more common early in treatment). Registered dietitians can ensure that, even with a reduced appetite, a person consumes enough calories, protein, vitamin, and minerals to mitigate some of the effects of potentially rapid weight loss, such as hair loss and lean muscle mass deterioration. They can also recommend foods that are easier to tolerate for people experiencing adverse side effects of the drugs. 

Behavioral health challenges and opportunities

Too often, people with obesity are blamed for having the condition. This leads to weight-based stigma and pervasive negative perceptions of people with overweight and obesity, exacerbating the stress that living in a larger body can bring.

More than 20% of people with obesity report feeling weight stigma and shame from their primary care provider which often leads to less engagement and poorer outcomes. People who face weight stigma are more likely to engage in unhealthy eating behaviors. Weight loss interventions, including GLP-1s, can also exacerbate disordered eating. 

Before prescribing GLP-1s, it’s crucial that a physician and a licensed therapist screen patients for any behavioral support needs. Licensed therapists can address deeply-rooted emotional issues related to how and why certain food is consumed. And registered dietitians can help watch for unhealthy eating patterns and offer guidance.

Some people who have obesity may be accustomed to using food as a coping mechanism for underlying mental health problems like depression and anxiety. A decreased appetite may trigger replacement coping strategies that are no less harmful. Mental health support and nutritional guidance are crucial to help people through significant lifestyle changes that take time to adopt.

While GLP-1s are undoubtedly exciting and effective promoters of weight loss, there are risks associated with their use. It’s important to provide continuous behavior change support to people taking these new drugs. Care teams of prescribing physicians, registered dietitians, and licensed therapists are the ideal way to deliver that ongoing support. By providing people with the necessary emotional and nutritional support alongside clinically-approved drugs, we stand a chance at quelling the obesity epidemic and achieving lasting weight loss results on a grand scale. 

Gretchen Zimmermann Headshot
Gretchen Zimmermann

Gretchen Zimmermann, RD, CDCES, is the Sr. Director of Cardiometabolic Care and Prescribing at Vida Health. Gretchen has led the development and growth of key clinical verticals and cardiometabolic programs, using evidence-based medicine and clinical interventions to inform best-in-class clinical care. She has more than 15 years of experience in healthcare and has specialized in bariatric nutrition, weight management, and diabetes in various inpatient and outpatient settings. Gretchen is especially interested in the intersection of physical health and mental health, particularly related to patients with diabetes and other chronic conditions.