A Dietitian’s Take on GLP-1 Medications for Weight Loss

Let’s talk about GLP-1RA medications, including looking at research on their benefits and challenges and key nutrition considerations — including concerns about weight regain after stopping meds.

How GLP-1 Meds Work

The GLP-1 hormone plays a key role in glucose regulation, but has a very short half-life in its natural form. GLP-1 receptor agonists (GLP-1RAs) are designed to replicate the hormone’s effects while overcoming its short lifespan. The medications work by mimicking this natural GLP-1 hormone, leading to multiple positive effects. GLP-1RAs make changes throughout the body, including:

Brain

GLP-1RA medications affect the brain by…

• Helping brain cells communicate 
• Protecting nerves from damage
• Supporting the growth of new brain cells
• Helping movement and coordination
• Reducing hunger signals
• May help with learning and cognitive function
• Lowering brain inflammation 

Heart

GLP-1RAs can support cardiovascular health because they…

• Protect the heart and blood vessels
• Reduce inflammation
• Promote release of hormones to regulate blood pressure
• Lower unhealthy fats in the blood
• Improve blood vessel function
• Reduce damage caused by low oxygen levels

Liver

These medications also support liver health. They…

• Lower amount of sugar produced by the liver
• Lower certain liver enzymes linked to damage
• Help with fatty liver disease

Pancreas

GLP-1RA medications…

• Help the body make more insulin
• Support insulin release to manage blood sugar levels
• Protect insulin-producing cells
• Help these cells grow and function

GI Tract

These medications support GI health by…

• Slowing down how quickly food leaves the stomach
• Reducing movement in the intestines, which can affect digestion 

As you can see, GLP-1RAs have vast potential far beyond sustained weight loss and weight reduction. However, researchers are still developing a picture of the drugs’ immediate side effects and long-term outcomes.

A Dietitian’s Role in GLP-1 Medications

Studies find that GLP-1RAs reduce overall food intake by 16–39%. This decrease can be beneficial for patients who are in treatment for obesity, and result in significant weight loss, but eating less can have serious impacts on nutrient intake. A recent review found: 

• Lower intake of fats and carbohydrates, with some studies showing reduced protein consumption.
• Shifts in food preferences, with decreased desire for high-fat foods and an increased preference for low-fat, sweet foods.
• Potential risk of nutrient deficiencies, particularly if protein and micronutrient intake are not monitored.
• Regular nutrition support results in fewer cravings, reduced emotional eating, and better control over food choices.

We strongly advocate for the inclusion of registered dietitians in every GLP-1RA intervention to optimize dietary quality and support long-term success beyond medication use.

Quality of Life on GLP-1RAs

Medications like Ozempic, Wegovy, and Zepbound are increasingly prescribed for type 2 diabetes and obesity. While GLP-1 RAs may seem like miraculous treatments, it’s important to understand how this drug can impact quality of life. 

• Cost – insurance coverage varies widely, and the meds can be expensive
• Availability – supply chain issues and high demand have led to frequent shortages
• Follow-ups – regular medical check-ins will be necessary to monitor effectiveness, manage side effects, and adjust dosages
• Nausea / vomiting – these GI side effects are especially common early in treatment
• Diarrhea / constipation – digestive issues can be persistent and require dietary or medical management
• Anxiety about timelines– some patients worry about long-term dependence, weight regain after stopping, and the uncertainty of lifelong treatment

​​Studies like this one find that education, appropriate dosing, and ongoing monitoring from physicians and dietitians are essential to balancing benefits with potential risks.

What are the Risks?

A common side effect like nausea or abdominal pain often improves within a few weeks of starting GLP-1 medication, and can be managed with nutritional support. Here are some other risks to note before you or a loved one begins treatment:

Gastrointestinal Nausea, diarrhea, vomiting, constipation, abdominal discomfort, and indigestion are common, especially right after starting meds.	Facial Loss of facial fat, collagen, and elastin may lead to sagging skin and more pronounced wrinkles.
Oncological Potential increased risk of thyroid cancer, including medullary thyroid carcinoma.	Renal Some studies suggest a link to acute kidney injury or other kidney complications.
Glycemic Considerations When combined with other glucose-lowering drugs, there’s increased risk of hypoglycemia.	Dermatological Skin reactions can include rashes, redness, and itching, as well as panniculitis with certain formulations.
Pancreas Elevated pancreatic enzymes, an increased risk of pancreatitis, and gallstone formation due to rapid weight loss may occur.	Cardiovascular Some individuals experience an increased heart rate.
Allergenic & Immune Responses The formation of antibodies can lead to hypersensitivity reactions, with rare cases of anaphylaxis.	Musculoskeletal There may be an effect on bone fracture risk.

Weight Management Beyond the Meds

Up to 75% of individuals taking GLP-1 medications for weight loss stop treatment within a year. Research indicates that stopping the meds often leads to rapid weight regain and worsening cardiometabolic health. However, studies have not yet investigated the impact of nutrition counseling on this trend.

Here’s what we do know: registered dietitians can help establish sustainable health behaviors that mimic some of the effects of GLP-1RAs.  

These behaviors include:

• Planning meals and snacks to optimize satiety while maintaining energy balance
• Including physical activity in your weekly routine
• Learning to recognize and respond to your internal hunger and fullness cues 
• Improving your relationship with food to decrease/cope with “food noise” 

If you or someone you know is currently taking GLP-1RAs (or planning to begin treatment), we recommend incorporating the drugs into a long-term management plan that includes dietitian support and lifestyle changes. Get matched with a Culina Health provider today.