Dr. Adhiti K, Consultant, Internal Medicine, Dr. Mehta’s Hospitals
Social media has crowned GLP-1 receptor agonists as “miracle” weight loss drugs. Celebrities talk about them. Friends recommend them. Pharmacies struggle to keep them in stock. But are these injections really the answer to obesity?
Obesity is a complex chronic disease characterized by excessive body fat and is often linked to conditions such as diabetes and hypertension. GLP1 receptor agonists are a class of drugs that were initially developed for diabetes but are currently playing an important role as weight loss medications.
When we eat, carbohydrates are broken down into glucose, which stimulates the pancreas to release insulin, the hormone responsible for regulating blood glucose levels. Insulin helps tissues utilise glucose, thereby lowering blood glucose levels. In diabetes, this finely regulated relationship becomes impaired.
GLP-1 receptor agonists enhance this natural pathway, helping improve blood glucose control. They were therefore initially introduced for the treatment of type 2 diabetes.
GLP-1 (Glucagon-Like Peptide-1) is a natural hormone released by the intestine after meals. It signals the brain that we are full, slows stomach emptying and improves insulin release. GLP1 receptor agonists mimic the action of this hormone. They promote the release of insulin in response to food intake, increase satiety, and delay gastric emptying. Together, these effects reduce food intake and promote weight loss.
Although several medications belong to this class, semaglutide and tirzepatide have demonstrated the greatest weight-loss benefits in clinical trials. In the STEP trials, participants receiving semaglutide lost an average of around 15% of their body weight over approximately 68 weeks when combined with healthy lifestyle measures. More recently, the SURMOUNT-1 trial demonstrated that tirzepatide, a newer medicine acting on both GLP-1 and GIP receptors, produced average weight loss of 20% or more in many participants. These results represent a major leap forward compared with older weight-loss medications.
Perhaps the greatest benefit extends well beyond the weighing scale. Studies have shown that these medicines not only improve blood glucose control but also offer significant cardiovascular and kidney protection.
When we combat diabetes and obesity, we are not merely chasing lower numbers on the scale, but we are also trying to reduce heart attacks, strokes, kidney disease and improve quality of life. Recent landmark studies have shown that GLP-1 agonists can reduce cardiovascular events in people at high cardiovascular risk. Semaglutide has demonstrated cardiovascular benefits even in people with obesity who do not have diabetes. In other words, these medicines may help people live not just lighter, but also healthier.
Nausea, vomiting, bloating and constipation are the most common side effects encountered with these medicines, especially during the first few weeks. Weight loss may also be accompanied by some loss of muscle and bone mass, making adequate protein intake and resistance exercise important during treatment. Rare but important risks include pancreatitis and gallbladder stones. These medicines are generally avoided in individuals with a personal
or family history of certain rare thyroid cancers, based primarily on findings from animal studies. They also require caution in patients with severe diabetic retinopathy. This is why they should always be prescribed after careful medical evaluation and in consultation with your physician.
It is also important to understand that these medicines work best as part of a comprehensive weight management programme. Healthy eating, regular physical activity, adequate sleep and stress management remain the foundation of long-term success. In fact, studies show that stopping treatment often leads to rebound weight gain, thus highlighting that obesity is a chronic disease requiring ongoing care rather than a short-term fix.
While most major studies have evaluated these medicines for approximately one to two years, the optimal duration of treatment is still being determined. The arrival of GLP-1 agonists marks one of the most exciting advances in obesity medicine in decades. They have changed the conversation from blame to biology and from willpower alone to evidence-based treatment. Used wisely, under medical supervision, they can be life-changing and can significantly improve long-term weight management in conjunction with lifestyle modification. However, they are not a substitute for healthy eating and regular physical activity. They are best appreciated as a powerful partner in an obese patient’s journey toward better health.
After all, the goal isn’t simply to lose kilograms. It’s to gain years of healthier living!