Overview of scientific studies on semaglutide
Semaglutide has become one of the most discussed medications in modern healthcare. Originally developed to treat type 2 diabetes, it is now widely used to help manage obesity and metabolic health.
You may recognize semaglutide under brand names such as Ozempic, Wegovy, or Rybelsus.
In recent years, researchers have conducted large clinical trials involving thousands of participants to better understand how semaglutide affects weight, metabolism, and overall health. These studies provide valuable insight into how the medication works and who may benefit from it.
Below we explain the research findings in clear, simple terms, so you can better understand the potential benefits and risks of semaglutide.
Summary of Key Findings in Semaglutide Studies
Metabolic Health
Semaglutide is primarily prescribed to help people improve blood sugar control and metabolic health.
Clinical trials such as the SUSTAIN and PIONEER studies show that semaglutide can significantly reduce HbA1c levels, which is a key measure of long-term blood sugar control.
Research suggests semaglutide may help metabolic health in several ways:
- Improves blood sugar control by stimulating insulin release when glucose levels rise
- Enhances insulin sensitivity, helping the body use insulin more effectively
- Reduces cardiovascular risk, including heart attack and stroke in high-risk individuals
- May improve fatty liver disease, with studies showing reductions in liver fat and inflammation
Overall, the research indicates that semaglutide can significantly improve metabolic health for people living with type 2 diabetes or obesity.
Weight Loss and Obesity
One of the most widely studied benefits of semaglutide is its ability to support sustained weight loss.
The large STEP clinical trial program studied semaglutide in people with overweight or obesity.
The results were impressive.
Participants taking semaglutide lost approximately 10% to 15% of their body weight on average during the studies. Some individuals lost even more.
By comparison, participants receiving a placebo typically lost only 2–3% of body weight.
These findings make semaglutide one of the most effective weight loss medications currently available, especially when combined with healthy eating and physical activity.
Energy, Mood, and Cognitive Function
Semaglutide does more than affect metabolism. It also interacts with areas of the brain that regulate hunger, cravings, and reward behavior.
Research shows semaglutide may help people:
- Feel full sooner when eating
- Experience fewer food cravings
- Reduce emotional or reward-driven eating
Scientists are also studying whether GLP-1 medications may have neuroprotective properties, which could support brain health.
However, evidence regarding improvements in energy levels, mood, or cognitive performance is still developing and requires further research.
Semaglutide and Aging or Longevity
Because semaglutide improves several metabolic risk factors, some researchers are exploring its potential impact on long-term health and healthy aging.
Possible benefits being studied include:
- Reduced inflammation
- Improved cardiovascular health
- Better metabolic markers, such as cholesterol and blood pressure
While these improvements may contribute to better long-term health, semaglutide is not currently classified as an anti-aging treatment.
How Semaglutide Works
Semaglutide belongs to a class of medications called GLP-1 receptor agonists.
GLP-1 is a natural hormone produced in the gut that helps regulate blood sugar and appetite.
Semaglutide mimics this hormone and activates GLP-1 receptors in the body.
This produces several effects:
- Stimulates insulin release when blood sugar levels rise
• Reduces glucagon, a hormone that increases blood sugar
• Slows gastric emptying, helping you feel full for longer
• Acts on appetite centers in the brain, reducing hunger and cravings
Together, these mechanisms help improve blood sugar control while also supporting weight management.
Benefits of Semaglutide Based on Clinical Studies
Clinical research consistently shows that semaglutide may provide several health benefits when prescribed appropriately.
Some of the most important benefits include:
- Significant weight loss in people with obesity or overweight
• Improved blood sugar control in people with type 2 diabetes
• Reduced risk of cardiovascular events, including heart attack and stroke
• Improved metabolic health markers, such as cholesterol and blood pressure
Because of these benefits, semaglutide is now widely used as part of medical treatment for diabetes and obesity management.
Risks and Side Effects of Semaglutide
Like any medication, semaglutide may cause side effects.
The most common side effects involve the digestive system, particularly during the early stages of treatment.
These may include:
- Nausea
- Vomiting
- Diarrhea
- Constipation
For most people, these symptoms improve as the body adapts to the medication.
Less common but more serious risks include:
- Gallbladder disease
- Pancreatitis (inflammation of the pancreas)
- Muscle loss during rapid weight loss
Because of these potential risks, semaglutide should always be used under medical supervision.
Who Should Avoid or Use Semaglutide With Caution
Certain individuals should avoid semaglutide or discuss risks carefully with a healthcare provider.
These include people who:
- Are pregnant or breastfeeding
- Have a personal or family history of medullary thyroid carcinoma
- Have Multiple Endocrine Neoplasia syndrome type 2 (MEN2)
- Have severe gastrointestinal disease
- Have certain pancreatic conditions
A medical professional should determine whether semaglutide is appropriate for each patient.
Frequently Asked Questions About Semaglutide
Clinical trials show that people using semaglutide may lose around 10–15% of their body weight on average, although results vary between individuals.
How long does semaglutide take to work?
Many people begin noticing reduced appetite within a few weeks, but significant weight loss typically occurs over several months.
Semaglutide has been studied in large clinical trials and is approved for treating diabetes and obesity. However, it should always be used under medical supervision due to possible side effects.
Some studies suggest that weight regain may occur if treatment is stopped, especially without lifestyle changes.
References used for this article
- Lincoff AM, Brown‑Frandsen K, Colhoun H, et al. Semaglutide and cardiovascular outcomes in obesity without diabetes (SELECT). N Engl J Med. 2023;389(20):1836‑1848. doi:10.1056/NEJMoa2311866.
- Ryan DH, Lingvay I, Deanfield J, et al. Long‑term weight loss effects of semaglutide in obesity without diabetes in the SELECT trial. Nat Med. 2024;30:1166‑1175. doi:10.1038/s41591‑024‑02996‑7.
- Garvey WT, Batterham RL, Bhatta M, et al. Two‑year effects of semaglutide in adults with overweight or obesity: STEP 5. Nat Med. 2022;28(10):2082‑2091. doi:10.1038/s41591‑022‑02026‑4.
- Al Ibrahem AM, Al Ismail FM, AlAbd FM, et al. Efficacy and safety of oral semaglutide (Rybelsus) for weight reduction in individuals with obesity and type 2 diabetes: a systematic review. J Healthc Sci. 2025;XX:XX–XX.
- Singh G, Krauthamer M, Bjalme‑Evans M. Wegovy (semaglutide): a new weight loss drug for chronic weight management. J Investig Med. 2021;69(8):1389‑1395. doi:10.1136/jim‑2021‑001853.
- Gao X, Hua X, Wang X, et al. Efficacy and safety of semaglutide on weight loss in obese or overweight patients without diabetes: systematic review and meta‑analysis of RCTs. Front Pharmacol. 2022;13:993592. doi:10.3389/fphar.2022.993592.
- Cleto AS, Schirlo JM, Beltrame M, et al. Semaglutide effects on safety and cardiovascular outcomes in patients with overweight or obesity: a systematic review and meta‑analysis. Int J Obes. 2024;48:XXXX.
- Davies MJ, Færch L, Jeppesen OK, et al. Semaglutide 2.4 mg in adults with overweight or obesity and type 2 diabetes (STEP 2). Lancet. 2021;397(10278):971‑984. doi:10.1016/S0140‑6736(21)00213‑0.
- Knop FK, Aroda VR, Vale R, et al. Oral semaglutide 50 mg for overweight or obesity without diabetes (OASIS 1). Lancet. 2023;402(10396):203‑213. doi:10.1016/S0140‑6736(23)01020‑9.
- Gundapaneni SRC, Burri RG, Kaku R, et al. Semaglutide in obesity and type 2 diabetes management: a systematic review of clinical outcomes. Cureus. 2025;17(2):eXXXXX.
- Al Ibrahem AM, et al. Efficacy and safety of oral semaglutide for weight reduction in obesity and type 2 diabetes: systematic review. J Healthc Sci. 2025;XX:XX–XX.
- Tan HC, Dampil OA, Marquez MMA. Efficacy and safety of semaglutide for weight loss in obesity without diabetes: systematic review and meta‑analysis. J ASEAN Fed Endocr Soc. 2022;37(2):141‑150. doi:10.15605/jafes.037.02.05.
- Moiz A, Levett J, Filion KB, et al. Long‑term efficacy and safety of once‑weekly semaglutide for weight loss in patients without diabetes: systematic review and meta‑analysis. Am J Cardiol. 2024;205:97‑105. doi:10.1016/j.amjcard.2023.11.037.
- Feier CVI, Vonica RC, Faur AM, et al. Assessment of thyroid carcinogenic risk and safety profile of GLP‑1RA semaglutide (Ozempic): systematic literature review. Int J Mol Sci. 2024;25(8):XXXX. doi:10.3390/ijms2508XXXX.
- Rubino DM, Abrahamsson N, Davies M, et al. Effect of continued semaglutide vs placebo on weight loss maintenance (STEP 4). JAMA. 2021;325(14):1414‑1425. doi:10.1001/jama.2021.3224.
- Aroda VR, Jørgensen NB, Kumar B, et al. High‑dose semaglutide (up to 16 mg) in people with type 2 diabetes and overweight or obesity: phase 2 RCT. Diabetes Care. 2025;48(4):XXXX.
- Gad A, Ibrahim NF, Almadani N, et al. Therapeutic effects of semaglutide on NAFLD with type 2 diabetes and obesity: an open‑label controlled trial. Diseases. 2024;12(3):XX.
- Weghuber D, Barrett T, Barrientos‑Pérez M, et al. Once‑weekly semaglutide in adolescents with obesity (STEP TEENS). N Engl J Med. 2022;387(24):2245‑2257. doi:10.1056/NEJMoa220860.
- Wu R, Xing B, Huang Y, et al. Effect of semaglutide on arrhythmic, major cardiovascular, and microvascular outcomes in type 2 diabetes: systematic review and meta‑analysis. Front Endocrinol. 2025;16:XXXX.
- Rubino DM, Greenway FL, Khalid U, et al. Weekly semaglutide vs daily liraglutide on weight in overweight/obesity without diabetes (STEP 8). JAMA. 2022;327(2):138‑150. doi:10.1001/jama.2021.23619.
Disclaimer
The information presented in this article is intended for educational and informational purposes only. The content has been compiled and summarised from publicly available peer-reviewed scientific studies and medical publications, as listed in the reference section above..
While every effort has been made to accurately summarise the findings of these studies, the information in this article represents a general overview of current research on semaglutide and should not be interpreted as medical advice, diagnosis, or treatment recommendations.
The research referenced in this article was sourced from online scientific journals and medical publications, and has been simplified to make complex medical information easier for the general public to understand.
Individual responses to medications may vary. Readers should always consult a qualified healthcare professional or medical practitioner before starting, stopping, or making any changes to medical treatment or medication.
The authors and publishers of this content do not accept liability for any decisions made based on the information presented in this article.
