The groundbreaking effectiveness of medications like Ozempic (semaglutide) and Mounjaro (tirzepatide) has significantly changed the landscape for treating Type 2 diabetes and obesity. Many individuals have reported losing between 15 to 20 kilograms and achieving remarkable blood sugar management, sparking considerable enthusiasm. However, there are also patients who feel let down when they do not replicate such outcomes, prompting a critical question: why do these treatments not yield the same results for everyone if they are so potent?
The explanation is straightforward yet frequently misconstrued. These drugs are indeed powerful, but they are not infallible solutions. As with any medical treatment, the effectiveness varies because each person has a unique biological makeup.
In clinical settings, the responses from patients typically fall into four main categories. About 60% of patients see significant improvements in both weight and blood sugar levels. Approximately 15% manage to lose a notable amount of weight but experience less than expected improvements in their diabetes management. Another 15% achieve excellent blood sugar control with minimal weight loss, while the remaining 10% exhibit only a slight response in both areas. Consequently, it is crucial to avoid assessing an individual’s progress by comparing it to someone else’s experience.
Both Ozempic and Mounjaro function by imitating natural gut hormones that play a vital role in metabolism regulation. Ozempic primarily activates the glucagon-like peptide-1 (GLP-1) pathway, whereas Mounjaro engages both the GLP-1 and glucose-dependent insulinotropic polypeptide (GIP) pathways, providing two synergistic mechanisms of action.
These hormones encourage insulin secretion when blood sugar levels increase, inhibit glucagon release (a hormone that signals the liver to release stored glucose), decrease glucose production in the liver, enhance glucose absorption by muscle cells, slow down gastric emptying, and, crucially, diminish appetite, which aids in calorie reduction. Rather than just lowering blood sugar, these medications tackle various underlying metabolic issues linked to Type 2 diabetes and obesity.
Despite these multiple mechanisms, individual responses can differ widely due to the inherent variability in human biology.
A significant factor influencing these differences is genetics. Studies indicate that certain genetic variations might lessen the effectiveness of GLP-1-based treatments. Ongoing research is examining variations in genes like PAM and differences in GLP-1 and GIP receptors. An analogy often used is that of a key and a lock; if the lock’s structure varies due to genetic factors, the key may not fit perfectly, leading to a weaker response. Some individuals may also exhibit what researchers term GLP-1 resistance, where the body’s tissues do not respond effectively to the hormone, even when it is present.
However, genetics is just one aspect of a much broader picture. Factors like the duration of diabetes, the pancreas’s remaining insulin-producing capability, the level of visceral fat, sleep quality, stress, physical activity, dietary habits, medication adherence, and appropriate dosage adjustments all play crucial roles in determining treatment outcomes. Two patients on identical medications and doses may experience vastly different results due to their unique metabolic profiles.
If patients do not reach their targeted blood sugar levels or weight loss goals, stopping the medication is rarely the first advisable step. Instead, healthcare providers re-evaluate the comprehensive treatment strategy. They confirm the diagnosis, check if the medication has been taken consistently, ensure that the dosage has been adequately increased, assess whether sufficient time has elapsed for the medication to take effect, and review adherence to dietary and exercise guidelines. Only after a thorough consideration of these elements can a well-informed decision about any necessary therapy changes be made.
For those who continue to show insufficient progress, treatment is personalized. In some instances, incrementally increasing the dosage can enhance results. In other cases, combining GLP-1 receptor agonists with other medications, such as metformin or sodium-glucose cotransporter-2 (SGLT2) inhibitors, can lead to markedly improved outcomes, as these drugs target different physiological pathways.
Modern diabetes management emphasizes a tailored approach rather than relying on a single medication. Current guidelines from the American Diabetes Association highlight the importance of customizing treatment based not only on HbA1c levels but also on factors such as obesity, cardiovascular health, kidney function, and the overall health profile of each patient.
Another common misconception is that the injections alone lead to significant weight loss. In the pivotal clinical trials of tirzepatide, participants did not solely receive the medication; they also adhered to structured calorie-restricted diets and increased their physical activity throughout the study duration. The notable average weight loss of up to 22.5% over 72 weeks, particularly with the highest dose, was a result of the combined effects of medication and sustained lifestyle changes, rather than medication alone.
Thus, lifestyle modifications remain a cornerstone of effective treatment. A balanced diet that is calorie-controlled and high in protein and fiber, regular walking coupled with resistance training to maintain muscle mass, sufficient sleep of seven to eight hours per night, effective stress management, and consistent follow-up with healthcare professionals are essential for long-term success.
(Dr. Mohan serves as the Chairman of Dr. Mohan’s Diabetes Speciality Centre in Chennai.)
