If You’re on GLP-1 Medications & Not Working With A Nutrition Professional, You Might Be At Serious Risk
For decades, pharmaceutical companies and many others in the health and wellness space have been searching for that “magic cure” for weight loss, and the demand for this has only intensified as more and more Americans struggle with being overweight or obese. Furthermore, over the last few years, as GLP-1 drugs have hit the market for weight loss use, many people believe we have finally found that long-awaited solution.
As a Certified Nutrition Specialist (CNS), my opinion has stayed neutral. I can see the great benefit these medications have had on some individuals who have spent years, or a lifetime, struggling with their weight, and I think there is a benefit to using them in those situations. However, I do recognize the notable long-term and potentially irreversible damage these medications can have if these patients do not have proper nutritional counseling during their time of use.
But Before We Dive Deeper- What Are GLP-1 Medications?
Glucagon-like peptide-1 receptor agonists, or GLP-1 RAs for short, are a man-made or synthetic product that mimics natural GLP-1 in the body. On the other hand, naturally produced GLP-1 is an amino acid that is secreted in the intestines following food consumption. It is used to send signals to the brain and the pancreas to increase insulin production, glucose uptake into cells, blood sugar regulation, and that feeling of fullness in your stomach. It may also increase taste sensitivity.1,2
Similarly, the synthetic version of GLP-1 mimics this same action in the body by attaching to the same receptors that natural GLP-1 does- without having to eat anything.1
This product was first discovered as a substance in Glia monster venom in the 1990’s, and after going through clinical trials, it was approved by the FDA in 2005 and was first used in drugs to treat type 2 diabetes.1
Interestingly, doctors noticed that patients on the drugs were also losing weight, which led to GLP-1 RAs being used for weight loss alone. Among the first GLP-1 drugs were Ozempic and Wegovy, which produce 10-15% weight loss, and now we are seeing even more effective formulas such as Mounjaro and Zepbound with up to 18% weight loss. Additionally, there are even more drugs on the way, claiming to have up to 24% weight loss.1
That May All Sound Great, But There’s A Catch.
Like most medications, GLP-1 RAs don’t come without risks and potential side effects. Although when it comes to GLP-1 medications, many of these risks can be addressed by implementing well-thought-out nutrition and lifestyle programs.
These risks and challenges include:
- Gastrointestinal Side Effects: It’s common for patients to experience nausea, vomiting, constipation, diarrhea, bloating, and acid reflux.1,3
Nausea is noted as the most common GI side effect, and it often happens after long periods without eating, such as several hours between meals or overnight. A common problem with this is that some individuals will skip eating because they feel nauseous, but this only makes the symptoms worse.
In regard to constipation, this is going to slow down your body’s ability to eliminate wastes. Your gastrointestinal tract is one of your body’s main channels of detoxification, so when you are not having normal bowel movements every day, this leads to an increased likelihood of certain toxins or hormones (i.e., estrogen) getting reabsorbed into the body and may lead to a higher toxin burden and/or estrogen dominance.4
Lastly, if individuals are vomiting regularly or having diarrhea, it means that they are not going to be absorbing the food that they do eat properly, which will increase the likelihood of nutrient deficiencies. - Macronutrient & Micronutrient Deficiencies: Many individuals starting these medications see a significant reduction in appetite and food intake, resulting in 16%-39% fewer calories than they normally consume. As a result, this can greatly reduce their intake of essential vitamins and minerals such as calcium, zinc, magnesium, iron, and vitamins A, D, E, K, C, and B vitamins like B1 and B12. This will also reduce their intake of macronutrients, including protein, carbohydrates, and fat.3
Insufficient intakes of nutrients may lead to symptoms such as excessive hair loss, muscle weakness, dry and itchy skin, poor wound healing, reduced immune function, and easy or unusual bruising.3 - Muscle and Bone Loss: When someone undergoes rapid weight loss, it frequently leads to both fat loss and muscle loss. Some research has shown that muscle mass loss in females undergoing rapid weight loss ranges from about 10%-15% and from 20%-25% in males, without incorporating strength training. It’s also very likely that low protein consumption also contributes to muscle loss.3
Moreover, rapid weight loss can also affect bone density and bone health. However, this impact is influenced by age, sex, initial body weight, rate of weight loss, physical activity, and intake of protein and other important nutrients for bone health.3
- Weight Regain After Stopping: Within one year after people stop taking GLP-1 medications, they gain up to two-thirds of the weight that they lost, on average. And unfortunately, most of that weight that they gain back is fat. Any lean muscle or bone mass that they lost is less likely to return, and in some cases, this muscle and bone loss may be permanent.3,5
The Importance of GLP-1 Nutrition Counseling
It’s clear that there is a strong need and growing demand for integrating nutritional counseling with the use of GLP-1 medications.1,3,5 In order to help patients who are taking these medications not only improve their results, but also increase their chances of keeping the weight off long term, establishing healthy eating habits, and preserving bone health, muscle mass, gut health and nutrient status- it should be strongly encouraged or required that they work with a nutrition professional that specializes in GLP-1 nutrition counseling.
A Joint Advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society highlights 8 nutritional priorities for reducing the risk of GLP-1 medications and maximizing their benefits.3 These include:
- Lead with a patient-centered approach: A big key to long-term success is personalizing a therapeutic care plan for patients that centers around a holistic approach to health and is not just focused on weight loss alone.
- Conduct a baseline nutrition assessment: It’s vital to understand where patients are starting from and what their health history, nutritional needs, and goals are.
- Manage GI side effects: A CNS can help make nutritional recommendations that help alleviate or reduce the risk of constipation, diarrhea, nausea, or other GI side effects that appear.
- Navigate dietary preferences and intakes: Patients who take GLP-1 medications may notice changes in their food preferences and their habits around eating. Having professional guidance can help make these shifts more beneficial and supportive for their health.
- Prevent and correct nutritional insufficiencies and deficiencies: Changes in eating habits while on GLP-1 medications can increase the risk of nutrient deficiencies, so working with a nutrition professional can help to minimize someone’s risk of this happening.
- Preserve muscle and bone mass: Your muscles and bones require certain nutrients to maintain their mass, so it’s an important goal for a CNS to make sure their patients are getting what they need to maintain healthy muscles and bones.
- Support healthy and sustainable weight loss: Although GLP-1 medications support weight loss in many individuals, there are often root causes that led to someone gaining that weight in the first place. Working with a CNS can help you uncover those underlying causes while simultaneously supporting your unique needs on these medications to ensure you have a fully personalized and sustainable plan that allows you to lose weight and keep it off.
- Encourage holistic lifestyle practices: Supporting weight loss requires much more than just nutrition- it’s just one piece to the puzzle! Nutrition professionals can help you integrate other important lifestyle pieces as well, such as improving sleep quality, stress management, and increasing movement/exercise.
If we truly want to see people improve their health and quality of life, and reduce their risk of potentially serious side effects of taking GLP-1 RAs, it’s going to be vital to follow these key nutritional priorities when supporting these individuals.
Conclusion
Although it seems like we have found the “magic cure” for weight loss, it’s clear to see that it does not come without serious risks. As a CNS who supports clients regularly with weight loss, I have had clients come to me who have been on GLP-1’s in the past, and in all cases, they had gained back what they had lost and oftentimes more than what they originally lost.
That is why I want to help people who are on or considering these medications to know that it’s vital for them to get proper nutrition counseling because these meds may cause more harm than good to their bodies if they aren’t provided with the right macro and micro nutrients for muscle, bones, and overall health. Plus, there is likely a root cause that led to the weight gain in the first place, and it’s important to figure that out if you want to see results that truly last.
Learn more about working with me HERE.
REFERENCES
1. Voss L. GLP-1 nutrition counseling guide for dietitians. NutritionEd.org. Updated October 8, 2025. Accessed February 22, 2026. https://www.nutritioned.org/what-is-glp-1-nutrition-counseling/
2. Zengul AG, Voss L, Demark-Wahnefried W, et al. Optimizing nutrition, diet, and lifestyle communication in GLP-1 medication therapy for weight management: a qualitative research study with registered dietitians. Nutr Health. 2024;30(4):685-694. doi:10.1177/02601060241285437
3. Mozaffarian D, Agarwal M, Aggarwal M, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Am J Clin Nutr. 2025;121(2):295-305. doi:10.1016/j.ajcnut.2024.11.001
4. Zengul AG, Demark-Wahnefried W, Barnes S, et al. Associations between dietary fiber, the fecal microbiota and estrogen metabolism in postmenopausal women with breast cancer. Nutr Cancer. 2021;73(7):1108-1117. doi:10.1080/01635581.2020.1784444
5. Long-term success of GLP-1s hinges on more than just a prescription. Tufts Now. June 4, 2025. Accessed February 22, 2026. https://now.tufts.edu/2025/06/04/long-term-success-glp-1s-hinges-more-just-prescription



