Unless you were a GLP-1 user before the Ozempic craze, you might've never heard about it—let alone considered using it. But as the popularity of Ozempic continues to rise, you might be a current GLP-1 user, a prospective GLP-1 user, or a loved one of a GLP-1 user.
As a weight loss physician with over 20 years of experience, I recognize the transformative potential of GLP-1 medications for their users. But to maximize GLP-1's effectiveness and steep money spent on them, it's crucial to be informed about the nuances and details that lie ahead.
In the upcoming sections, we'll explore all questions related to "What are GLP-1 medications?" including their benefits and risks. We'll also discuss how bistroMD can enhance both your short-term and long-term success. Let's dive in!
What Is GLP-1?
To fully grasp GLP-1 medications, it's helpful to understand what 'GLP-1' stands for on its own. Glucagon-like peptide-11 (GLP-1) is an incretin hormone secreted by the intestinal epithelial endocrine L-cells2 in response to food. GLP-13 also functions as a neurotransmitter and is synthesized in the brain as part of the central nervous system (CNS).
GLP-1's main role is to regulate blood sugar (glucose) levels by promoting insulin and suppressing glucagon secretions. Both insulin and glucagon are hormones produced in the pancreas: insulin lowers blood glucose, while glucagon raises it.
GLP-1 also delays gastric emptying by inhibiting gastrointestinal (gut) motility via the ileal brake4, a feedback mechanism activated by unabsorbed dietary components in the ileum (portion of the small intestine). The ileal brake promotes efficient digestion and nutrient absorption while controlling appetite and reducing food intake.
All this to say, these primary actions are why GLP-1 medications exist and are prescribed.
What Are GLP-1 Medications?
Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs)5—also known as GLP-1 receptor agonists, incretin mimetics, and GLP-1 analogs—are a class of medications primarily used to treat type 2 diabetes. In some cases, especially as of late, GLP-1 RAs are used to treat obesity.
It's important to emphasize that all GLP-1 medications have received approval from the Food and Drug Administration (FDA) for treating type 2 diabetes. Yet, only Saxenda® and Wegovy® have approval for obesity treatment, even though Ozempic® and other GLP-1 RAs are frequently prescribed off-label for weight loss.
Also worth noting, Ozempic® and Wegovy® are essentially the same drug, specifically a GLP-1 known as semaglutide. The primary distinction between them is their approved indications: Wegovy® for weight loss and Ozempic® for diabetes. Additionally, Wegovy® is prescribed at higher doses.
A 2023 update6 tells us there are currently seven GLP-1 receptor agonists, including:
• Brand name: Byetta®
• Dosage: twice-daily injection
• Brand name: Bydureon®
• Dosage: once-weekly injection
• Brand name: Adlyxin®
• Dosage: once-daily injection
• Brand names: Victoza® and Saxenda®
• Dosage: once-daily injection
• Brand names: Trulicity®
• Dosage: once-weekly injection
• Brand names: Ozempic® and Wegovy®
• Dosage: once-weekly injection
• Brand name: Rybelsus®
• Dosage: once-daily injection
We also can't overlook tirzepatide (branded as Mounjaro®), which is the first agonist that targets both glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors. Acting on both GLP-1 and GIP receptors, Mounjaro® may be more effective in reducing blood sugar levels and weight than GLP-1 medications. While Mounjaro® is only FDA-approved to treat type 2 diabetes at this time, it may gain approval for weight loss in the near future.
Now you might wonder, "What makes each GLP-1 different, and which is right for me?" That must be a discussion between you and your doctor, as a 2021 review7 tells us the most notable differences between GLP-1 receptor agonists—like pharmacokinetics8 (how the body interacts with the medication), dosing frequency, and administration—can impact the GLP-1 RA's efficacy, tolerability, and patient satisfaction.
At their core, however, glucagon-like peptide-1 receptor agonists9 act to enhance the body's natural response to food by mimicking the GLP-1 hormone.
GLP-1 Agonist Mechanism of Action
A drug's mechanism of action (MoA)10 describes the biological interaction through which a molecule produces its pharmacological effect—or simply explains how the drug works in the body.
Below reiterates how GLP-1 RAs can help manage weight and blood sugars, particularly as GLP-1 activity6 may be decreased in people with type 2 diabetes.
Stimulates Insulin Release
When blood glucose levels increase, GLP-1 RAs stimulate the release of insulin. This allows the body's cells to use sugar for energy and supports healthy blood sugar levels.
Suppresses Glucagon Secretion
When blood glucose dips too low, glucagon is released to raise blood sugar levels by converting glycogen (the storage form of glucose) into glucose. GLP-1 RAs, however, work to suppress glucagon secretion to reduce blood glucose levels.
Slows Gastric Emptying
GLP-1 medications slow the rate at which the stomach empties, suppressing appetite and leading to subsequent weight loss. Slowing down stomach emptying also leads to a gentler, lesser increase in blood sugar levels after eating.
As an incretin hormone11, GLP-1 promotes satiety through both the central nervous system (CNS), which involves the brain and spinal cord, and peripheral pathways, which refer to processes or parts outside of the CNS. Peripheral mechanisms12 regulate appetite by monitoring the stomach's actions, such as how quickly it empties, which helps signal to the brain when we're full.
Research13 also indicates that GLP-1 medications reduce the activation of appetite- and reward-related brain regions, such as the insula and amygdala, thereby reducing food intake.
Benefits of GLP-1 Medications
The most well-known benefit of GLP-1 medications is their ability to manage type 2 diabetes effectively. GLP-1 RAs have also gained momentum to promote weight loss and provide additional health benefits.14
A 2021 review15 emphasizes that for people newly diagnosed with type 2 diabetes, healthy lifestyle changes—including proper nutrition and regular physical exercise—should be the primary line of treatment. Oral medications, such as metformin, are often prescribed if lifestyle interventions prove ineffective in improving glycemic control.
If blood sugar levels remain uncontrolled despite lifestyle changes and oral medications, GLP-1 RAs are recommended as the preferred first injectable glucose-lowering therapy, even before insulin.
Studies16 demonstrate that GLP-1 RAs enhance glycemic control and decrease hemoglobin A1C (HbA1c) levels by approximately 0.8-1.6%. HbA1c measures the average blood sugar levels over the past three months, corresponding to the average lifespan of red blood cells (RBCs) and indicating the extent to which the RBCs are "sugar-coated."
For reference, the American Diabetes Association (ADA) advises that the target A1C for most adults with diabetes should be below 7%.
While GLP-1 medications are an effective weight loss aid, results can vary based on the type of GLP-1 RA used and their dosage and duration. However, evidence-based ballparks include:
• Patients taking Wegovy (a semaglutide) for up to 68 weeks lost up to 12.4% of initial body weight.
• Individuals taking liraglutide17 for one year lost an average of 11.8 pounds in tandem with intensive behavioral therapy.
• During a 40-week study18, people receiving 1 milligram of Ozempic lost an average of 13 lbs while those receiving a 2-milligram dose lost an average of 15 pounds.
• Patients taking semaglutides19 achieved total body weight loss of 5.9% at 3 months and 10.9% at 6 months, which may associated with other lifestyle interventions like diet.
Moreover, a 2022 review20 suggests diabetic patients who take GLP-1 RAs lose 4-6.2% more weight than those taking a placebo. The weight loss difference for non-diabetic individuals taking GLP-1 RAs compared to a placebo is more pronounced, ranging from 6.1-17.4%.
Diabetic participants who took liraglutide or semaglutide often lost 15% or more of their body weight, a result not seen with other treatments or lifestyle changes alone. Losing this much weight can significantly alter the course of their diabetes.
But all studies included lifestyle modifications as part of the protocol!20
A 2020 review21 highlights cardiovascular (heart) disease is the leading cause of morbidity and mortality among individuals with diabetes. Alarmingly, almost half of diabetic patients pass away from cardiovascular disease!
Obesity also stands as another significant risk factor. Remarkably, data even losing 5% of body weight22 can improve heart health metrics—such as triglycerides, total cholesterol, and low-density lipoprotein (LDL) cholesterol—thereby reducing heart disease risk.
Many studies14 show GLP-1RAs effectively treat cardiovascular conditions—like atherosclerosis and hypertension—in non-diabetic and diabetic groups. Moreover, the American Heart Association (AHA)23 recommends that neurologists use GLP-1RAs as part of their stroke prevention strategies for patients with type 2 diabetes at high risk of stroke.
Disease Prevention & Management
Beyond reducing the risks of heart disease, GLP-1 RAs have also been explored for prevention and managing:12
• Chronic kidney disease (CKD)
• Neurological diseases, including Alzheimer's and Parkinson's diseases
• Non-alcoholic fatty liver disease (NAFLD)
• Polycystic ovary syndrome (PCOS)
And this list is likely just be the beginning, as overweight and obese individuals are at significant risk of many serious health conditions like cancer and depression. They're also at greater risk of low quality of life, though GLP-1 RAs may help improve it hints a 2022 review.24
Pain medications—like opioids and long-term NSAID use—can be harmful and even fatal, often limiting their application in a clinical setting. However, GLP-1 RAs may be a safe and alternative treatment option.
While relatively few studies explore the mechanism of GLP-1 RAs in treating chronic pain, GLP medications are shown to reduce pain induced by formalin, cancer, and diabetes. GLP meds may also relieve intestinal pain caused by irritable bowel syndrome (IBS).25
GLP-1 Side Effects and Risks
With great benefits, is there a catch? If you're already a GLP-1 user, you likely already know alllll about them! But let's catch everyone else up to speed on some of the most common side effects of GLP-1s and any long-term risks.
Common Adverse Effects of GLP-1s
The most common adverse effects of GLP-1 receptor antagonists26 are gastrointestinal-related, including:
• Abdominal pain
• Dyspepsia/indigestion (upset stomach)
Nausea is the most common of the GI symptoms, affecting up to 50% of users, but the frequency often gradually reduces as therapy continues. However, GI-related symptoms are the primary reason for discontinuing GLP-1s.27
Other side effects and risks of GLP-1s include:
• Mild tachycardia (increased heart rate)
• Injection site reactions, such as itchiness and redness
• Hypoglycemia (low blood sugar)
Severe Risks & Contraindications
While less common, GLP-1s can pose severe risks such as intestinal blockage and gastroparesis28, which refer to the delay in gastric emptying without evidence of mechanical obstruction. Recent reports of intestinal blockages have prompted the FDA to add a warning label on Ozempic®, even though similar warnings are already present on Mounjaro® and Wegovy®.
It's worth highlighting, though, that poorly controlled diabetes itself elevates the risk of gastroparesis. Medical experts are currently investigating whether GLP-1s are directly responsible, whether the condition is due to uncontrolled blood sugars, or if it's a result of both factors combined.
There's also worry about GLP-1 medications causing thyroid cancer, and 2022 study29 shows an increasing trend between certain cancers and GLP-1 drug users. However, the Cleveland Clinic Journal of Medicine30 positions that the benefits of GLP-1 medications outweigh the risks and until more is known, there's little reason to withhold use unless coming from a personal or family history of medullary or follicular thyroid cancers.
Piggybacking off Cleveland Clinic's stance, the benefits of GLP-1 meds are likely to outweigh the risks for individuals with type 2 diabetes and obesity and NOT for vanity-driven users who solely want to quickly drop a few pounds for an upcoming event. Type 2 diabetes and obesity come with their own set of health risks, yet managing them effectively with GLP-1 RAs can truly transform these users lives.
Again, though, prospective GLP-1 users should discuss health and safety concerns with their doctor. This especially serves true for anyone who is pregnant or planning to become pregnant, breastfeeding, or managing a health condition.
How BistroMD Supports GLP-1 Users
As a meal delivery service, bistroMD supports GLP-1 users in countless ways—even beyond a nutritious and delicious menu!
Fulfills GLP-1 Instructions
GLP-1 medications absolutely can do wonders for their users, particularly when used alongside diet and exercise as instructed. All bistroMD meals are nutritionally balanced and take a quick few minutes to heat, leaving you with more time on your watch to check off the exercise box, create memories with your loved ones, and do anything else that fills your cup.
Targets Insulin Resistance & Weight Loss
As a weight loss physician, bistroMD is the byproduct of the breakthroughs I discovered in managing insulin resistance, blood sugars, and weight.
Related: What Is Insulin Resistance?
Your bistroMD menu provides a scientific balance of nutrients—specifically portion-controlled complex carbs, adequate lean protein, and healthy fats—to fuel your metabolism, stabilize blood sugars, minimize cravings, and preserve lean muscle tissue, especially during weight loss.
Helps Preserve Muscle Mass
Let's drive this point home: Protein is essential for preserving skeletal muscle and lean body mass (LBM), which support your metabolism and physical functioning. Unfortunately, evidence31 shows that drastic and rapid weight loss—whether from GLP-1 RA use, bariatric surgery, or diet-induced methods—can reduce LBM by up to 50% of the total weight lost!
Recognizing the critical functions of protein, including preserving lean muscle tissue and bolstering metabolism, we've made it a foundation of the bistroMD program. We advocate for the consumption of adequate lean protein every three hours. All of our meals provide an average of 25-30 grams of protein, while our snacks supply about 15 grams.
Provides Individual Support
"If you want to go fast, go solo. If you want to go far, go together," rings so much truth for meeting and sticking to any goal. And research32 supports that patients on GLP-1 RAs may benefit from additional support to improve long-term adherence—we have that fully covered at bistroMD.
Beyond providing favorable changes to metabolic processes, bistroMD recognizes just how invaluable support is to your success. As a bistroMD member, know that the entire bistroMD team is here to keep you inspired, motivated, and on track throughout your wellness journey!
Develops Sustainable Habits
One of the major pitfalls of using GLP-1 medications is solely relying on them to do the work, which can diminish their effectiveness and may backfire if or when they're discontinued for any reason. For long-term success, those on GLP-1 should cultivate healthy habits leading to lasting behavioral changes.
With bistroMD, you'll understand real portion control and learn to make health-conscious choices when dining out. And by working with our dietitian team, you'll receive personalized tips and education tailored to support your unique journey.
What Are GLP-1 Medications: Final Takeaways
GLP-1 medications mimic the GLP-1 hormone to assist in controlling blood sugars and weight, establishing them as effective treatment options for type 2 diabetes and obesity. Furthermore, GLP-1 RAs might also contribute to the prevention and management of conditions like heart disease.
While GLP-1 medications hold immense appeal and transformative potential, it's essential to understand that their efficacy is maximized when combined with a healthy diet, regular exercise, and other lifestyle modifications.
In essence, GLP-1s are a tool—not a Swiss Army knife that can tackle every challenge—and bistroMD can serve as another valuable instrument in your toolkit!
How we reviewed this article
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