Bmi Doctors

How Does Semaglutide Work?


Semaglutide, an increasingly popular drug used for the treatment of type 2 diabetes and, more recently, weight management, has piqued the interest of many in the medical community and beyond. Despite its increasing popularity, there remains a critical need to understand its mechanism of action, potential for weight loss, and best practices for its use.

Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist. GLP-1 is a hormone that’s naturally secreted by the intestines in response to food consumption. This hormone plays a pivotal role in glucose homeostasis, which involves the stabilization of blood glucose levels. It does this by promoting insulin secretion, inhibiting glucagon release (which otherwise increases glucose levels), slowing gastric emptying, and enhancing feelings of satiety (Drucker, 2018) In other words, semaglutide mimics the effects of this vital hormone. Upon administration, it binds to the GLP-1 receptor in the pancreatic beta cells, which leads to an increase in the secretion of insulin in a glucose-dependent manner. The result is a reduction in blood glucose levels (Nauck, et al., 2016). Moreover, semaglutide has an additional benefit — it reduces food intake by slowing gastric emptying and increasing feelings of fullness and satiety, factors that are pivotal for weight management (Farr, et al., 2016)

Speed and Impact of Semaglutide on Weight Loss

t’s important to note that weight loss results from semaglutide can vary significantly between individuals, with several factors influencing the outcome. These factors include individual metabolic characteristics, lifestyle choices, and the degree of adherence to the prescribed regimen. However, clinical trials have provided some insight into the typical timeframe for weight loss with semaglutide treatment. In these trials, significant weight loss was generally observable as early as 16 weeks into treatment. Moreover, weight loss was shown to continue at a steady pace for up to 68 weeks (Wilding, et al., 2021).

Maximizing the Results of Semaglutide

In order to maximize the effects of semaglutide, it’s essential to combine this medication with a healthy lifestyle. This means incorporating a balanced diet that’s low on the glycemic index and maintaining a regular physical activity schedule. This combination not only boosts the metabolic effects of semaglutide but also promotes overall health and wellness (Astrup, et al., 2020)5. Regularly consulting with a healthcare provider and strictly following the prescribed dosage regimen are also critical factors in achieving the best possible outcomes.

Weight Loss with Semaglutide

When discussing the potential for weight loss with semaglutide, it’s important to remember that results can vary widely between individuals. However, a meta-analysis of clinical trials provides a rough estimate of what can be expected. According to this analysis, patients experienced an average weight loss of approximately 1-2% of their baseline body weight after a month of semaglutide treatment (Khera, et al., 2021)

It’s also worth noting that weight loss typically increases progressively over the course of therapy. The most significant weight loss is typically observed after 68 weeks of consistent use, underscoring the value of long-term commitment to semaglutide treatment.

Dietary Recommendations for Semaglutide Use

Semaglutide doesn’t come with specific dietary restrictions. However, due to its mechanism of action, it is beneficial to limit the intake of foods with a high glycemic index and highly processed foods. These types of foods can lead to rapid spikes and falls in blood sugar levels, making it more difficult to manage glucose homeostasis (Blaak, et al., 2012)>7</span>Instead, a diet that includes plenty of whole grains, lean proteins, fruits, vegetables, and healthy fats is recommended. As always, specific dietary needs and recommendations should be discussed with a healthcare provider to ensure optimal results with semaglutide treatment. Semaglutide represents a significant advancement in the management of type 2 diabetes and obesity. Understanding its mechanism, benefits, and best practices for use is crucial for those seeking to enhance its benefits and improve patient outcomes. Despite its promise, it is important to remember that semaglutide should be used as part of a comprehensive treatment plan, which includes a healthy diet and regular physical activity.

Drucker, D. J. (2018). Mechanisms of Action and Therapeutic Application of Glucagon-like Peptide-1. Cell Metabolism, 27(4), 740-756.

Nauck, M., Weinstock, R. S., Umpierrez, G. E., Guerci, B., Skrivanek, Z., &amp; Milicevic, Z. (2016). Efficacy and safety of dulaglutide versus sitagliptin after 52 weeks in type 2 diabetes in a randomized controlled trial (AWARD-5). Diabetes Care, 39(7), 2668-2676.

Farr, O. M., Sofopoulos, M., Tsoukas, M. A., Dincer, F., Thakkar, B., Sahin-Efe, A., Filippaios, A., Bowers, J., Srnka, A., Gavrieli, A., Ko, B. J., Liakou, C., Kanyuch, N., Tseleni-Balafouta, S., Mantzoros, C. S. (2016). GLP-1 receptors exist in the parietal cortex, hypothalamus and medulla of human brains and the GLP-1 analogue liraglutide alters brain activity related to highly desirable food cues in individuals with diabetes: a crossover, randomised, placebo-controlled trial. Diabetologia, 59(5), 954-965.

Wilding, J. P., Batterham, R. L., Calanna, S., Davies, M., Van Gaal, L. F., Lingvay, I., McGowan, B. M., Rosenstock, J., Tran, M. T. D., Wadden, T.A., 

Wharton, S., Yokote, K., Zeuthen, N., Kushner, R. F. (2021). Once-Weekly Semaglutide in Adults with Overweight or Obesity. The New England Journal of Medicine, 384(11), 989-1002.

Astrup, A., Carraro, R., Finer, N., Harper, A., Kunesova, M., Lean, M. E., Niskanen, L., Rasmussen, M. F., Rissanen, A., Rössner, S., Savolainen, M.J., Van Gaal, L. (2020). Safety, tolerability and sustained weight loss over 2 years with the once-daily human GLP-1 analog, liraglutide. International Journal of Obesity, 36(6), 843–854.

Khera, R., Murad, M. H., Chandar, A. K., Dulai, P. S., Wang, Z., Prokop, L. J., Loomba, R., Camilleri, M., Singh, S. (2021). Association of Pharmacological Treatments for Obesity With Weight Loss and Adverse Events: A Systematic Review and Meta-analysis. JAMA, 315(22), 2424-2434.

Blaak, E. E., Antoine, J. M., Benton, D., Björck, I., Bozzetto, L., Brouns, F., Diamant, M., Dye, L., Hulshof, T., Holst, J. J., Lamport, D. J., Laville, M., Lawton, C. L., Meheust, A., Nilson, A., Normand, S., Rivellese, A. A., Theis, S., Torekov, S. S., Vinoy, S. (2012). Impact of postprandial glycaemia on health and prevention of disease. Obesity Reviews, 13(10), 923-984.

Questions and Answers: How does semaglutide work?

Semaglutide is a medication that improves the body’s ability to regulate blood sugar levels, reduces feelings of hunger, and has positive benefits to cardiovascular health. It is used in managing type 2 diabetes and comes in the form of an oral tablet or an injection taken once a week.

No, Semaglutide is not insulin. It should not be used as a substitute for insulin in the treatment of those with type 1 diabetes or diabetics who need insulin.

Semaglutide acts like the hormone glucagon-like peptide-1 (GLP-1), produced during and after eating, affecting appetite and hunger levels. It binds to and activates GLP-1 receptors to help increase insulin levels and slow digestion, controlling blood sugar levels and reducing heart attack or stroke risk in high-risk cardiovascular disease patients.

Common side effects include stomach problems like nausea, vomiting, upset stomach, and constipation. Others may experience allergic reactions, heart palpitations, trouble breathing, dehydration, vision changes, and, in some cases, problems with the kidneys, pancreas, or gallbladder.

Suitable candidates include adults with a BMI of 30 or more, adults with a BMI of 27-29 who have a weight-related comorbid condition like hypertension or type 2 diabetes, and children 12 years and older with a BMI in the 95th percentile or greater.

Semaglutide can be administered weekly, at any time of day but on the same day each week, with or without meals.

Semaglutide should be injected subcutaneously into the upper arms, abdomen, or thighs.

The maintenance dose of Semaglutide is 2.4 mg once weekly.

Semaglutide is contraindicated for those with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2, or in case of hypersensitivity to Semaglutide.

The most common side effects include nausea, diarrhea/constipation, feeling bloated, heartburn, belching, dizziness, vomiting, and upset stomach.


Dr. Jay Flottman

Dr. Jay Flottmann is a physician in Panama City, FL. He received his medical degree from University of Texas Medical Branch and has been in practice 21 years. He is experienced in military medicine, an FAA medical examiner, human performance expert, and fighter pilot.
Professionally, I am a medical doctor (M.D. from the University of Texas Medical Branch at Galveston), a fighter pilot (United States Air Force trained – F-15C/F-22/AT-38C), and entrepreneur.

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