As both the medical community and the general public come to more readily embrace the use of GLP-1 drugs for the purpose of weight loss, concerns have come to light regarding the lack of validated human studies. This article will discuss some of the more commonly voiced concerns regarding the use of this group of pharmaceuticals, including how to proceed safely with special populations.
Discontinued Use Skews Data
Most GLP-1 products on the market today are intended for the end users to remain on the medication for the long term. Unfortunately, for a variety of reasons, many individuals stop taking the drug before allowing it to make substantial differences in their health/body weight.
One research study found that adherence to GLP-1 products in real-world settings is substantially lower than reported in clinical trials. These disparate findings create concerns regarding the products’ effectiveness due to the significant number of individuals who choose to discontinue therapy within the first year. A primary factor affecting long-term adherence centers on cost: FDA-approved GLP-1 medications can run in excess of $12,000 a year, creating a financial burden for many individuals who could otherwise benefit from them. Other mitigating factors include insurance coverage changes, side effects, adverse events, and access disparities.
While users as well as physicians fully acknowledge and recognize the value of these products, particularly in terms of reducing dangerous obesity complications such as diabetes, cardiovascular events, and sleep apnea, individuals may not fully realize these health benefits if they discontinue use during the first year, and/or they fail to shed the desired amount of weight. Further research on the process/roadblocks to real-world persistence and adherence to GLP-1 products will help assess cost-effectiveness, identify needs for obesity care management programs, forecast future GLP-1 cost trends, and negotiate more favorable purchasing agreements with pharmaceutical manufacturers.
How Dietary Consumption Affects Overall Outcome
GLP-1 products, on their own, have more than demonstrated their efficacy in weight loss and in improving glycemic control. However, scant research data exist to address the extent to which food intake/food choices and related eating behaviors contribute to the overall process.
One research review aimed to evaluate the presence and quality of dietary data, nutritional counseling, and related behavioral measures among individuals using injectable medications. Although 57 trials out of several hundred reported lifestyle modification as part of the intervention, only 36 recorded food choices/dietary status and quantity of food intake. Among the 36 studies that collected dietary data, only 10 reported outcomes; of these, half used single-time-point assessments, such as dining at buffets. Seventeen trials assessed food cravings or eating behaviors, yet researchers found minimal uniformity in outcome reporting, study duration, or counseling frequency. In fact, the majority of these endeavors lacked detailed reporting on nutritional behavior components.
Despite the central role of diet in overall weight regulation, most clinical trials fail to report meaningful data on diet quality or food intake. Such indeterminate consideration for the importance and behavioral complexity of lifestyle changes in weight loss, coupled with underreporting, greatly limits scientists’ ability to interpret data and form general pictures of potential outcomes. Greater emphasis on standardizing/ reporting dietary and behavioral measures will foster a clearer understanding of how GLP-1s interact with real-world nutrition behaviors. This information can, in turn, help greatly with comprehensive obesity care.
Interestingly, most studies on eating behaviors vis-à-vis GLP-1 drug usage reflect only short-term outcomes. No long-term studies on how these products affect the brain reward system seem to have been documented.
Challenges with Pediatric Usage
One study sought to highlight the potential unintended/adverse consequences of administering GLP-1 medications to children and adolescents, particularly during periods of peak growth/development.
A major concern centers on the very premise of unbalanced and/or inappropriate reductions in caloric (energy) intake for this age demographic. Energy in children and adolescents, directly related to their caloric consumption, is expended not only on physical activity but also, unlike adults, on growth and development. The balance of energy intake and energy expenditure influences growth and health throughout one’s lifespan. As a prime example, we can consider how appropriate levels of exercise and diet during adolescence will influence bone mineralization; when intake of both seems adequate, one can greatly lessen the risk of osteoporosis and serious fractures later in life.
Almost any deviation from healthy levels of physical activity and diet can adversely impact the delicate balance between anabolism and catabolism. Professionals cite situations such as normal-weight adolescents who consistently have sedentary lifestyles, those who over-exercise to dangerous extremes, and young people dealing with obesity. Any of these scenarios invites risks of harmful growth patterns, as well as elevated levels of inflammation typically associated with cardiovascular disease risk.
Are GLP1s Fostering Eating Disorders?
The pharmaceutical industry recently accelerated development of oral GLP-1s; this ease of administration, combined with the proclivity among adolescents for risk-taking, may unwittingly create a perfect storm for potential abuse.
Adolescence marks a particularly vulnerable period in one’s development regarding self-esteem and satisfaction with appearance. Data from 2010 revealed that, in the United States alone, 2.7% of adolescents manifested eating disorders at some point in their lifetime, with females affected more than twice as often as males. Many young individuals turn to laxative abuse, induced vomiting, and appetite suppressants, along with food restriction. With the rapid expansion of social media resulting in greater exposure to body image ideals, diet culture, and GLP-1 prevalence, young users now have an even higher risk of developing eating disorders.
The dynamics and mechanisms of efficacy for many of today’s GLP-1 products were studied in depth prior to market launch; these studies focused mainly on adult populations but also included pediatric research. However, as newer formulations emerge, we must realize that adolescents’ bodies do not necessarily react as “miniature adults” and that these newer preparations could have adverse effects when prescribed for children. In addition, as many adult users have discovered, the potential exists for a lifelong dependency in order to keep body weight under control. This dynamic could get even more complex when these medications, expensive to begin with, get started at earlier and earlier ages. The question arises as to how caregivers/parents might implement lifestyle interventions alongside the GLP-1 medications, particularly as their youngsters enter peak growth periods and puberty, all while remaining vigilant to the signs of disordered eating behaviors.
Are Patients Receiving Optimal Lifestyle Counseling Intervention?
At least currently, prescription GLP-1s require a medical professional to hold the reins for dispensing and adjusting dosages. However, once a patient leaves the doctor’s office and pharmacy counter, he must often navigate this journey alone.
One critical issue that emerged across research trials offering lifestyle counseling was the most inconsistent use of Registered Dietitian Nutritionists (RDNs) as the sole providers of nutrition and lifestyle counseling. RDNs possess specialized expertise in medical nutrition therapy, dietary assessment, and behavioral counseling, making them uniquely qualified to guide individuals on the most effective lifestyle interventions for managing diabetes, either alongside GLP-1 use or on their own. Many research studies made only a cursory reference to the use of RDNs, raising the question of whether qualified professionals might provide lifestyle interventions.
A recurring challenge in these scenarios is inconsistent insurance coverage for medical nutrition therapy. Physicians may recommend RDN counseling, but access is limited when insurance does not cover these often costly services. As a result, this critical aspect of GLP-1 continuing care remains largely undocumented when reporting trial outcomes.
Additionally, patients must have a critical understanding of the sustainability of weight loss while on GLP-1s, especially since patients often regain approximately two-thirds of the weight initially lost within 1 year of stopping the medication, despite the drugs’ intended long-term use. These high rates of discontinuation further underscore the need for RDN involvement, both to support sustainable behavioral change and to provide continuity of care during potential lapses in medication use.
Keeping an Eye on Uncertain Risks
One current body of research seems to indicate that GLP-1 use may align with adverse effects in both the eyes and other distant organ systems. Although some findings yielded mixed results, most studies recommend that physicians consider the specific drug formulations and individual patients’ clinical characteristics prior to starting them on GLP-1 therapies. Several studies show that GLP-1 use may actually benefit retinal health, going so far as to show some protection against the development of diabetic retinopathy (DR) and other age-related ocular conditions. Additionally, some clinical trials point to potential reductions in blood pressure, improved lipid levels, and decreased inflammation – all factors that play key roles in retinal health.
In stark contrast, a few studies have shown that GLP-1 use may align with worsening retinal health and DR progression. Despite this evidence and that of other ocular complications associated with GLP-1 use, the mechanisms underlying these changes remain poorly understood. These challenges must be considered by medical professionals and end users alike before starting long-term use of these medications.
Throughout 2024, more research studies focused on how GLP-1 medications influenced type 2 diabetes rather than on weight loss. In addition, these studies lacked an in-depth, analytical approach across all GLP-1 user groups. I didn’t see any area of experience or different viewpoints on usage well represented. These findings highlight a need for more robust qualitative research conducted across all diverse user groups. Experts and skeptics alike agree that the industry must address this evidence gap with some degree of urgency in order to ensure the appropriate prescribing/dispensing of GLP‐1 medications. Furthermore, the industry might choose to prioritize how users receive support from services best suited to their needs.
References
https://pmc.ncbi.nlm.nih.gov/articles/PMC12361690
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