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Obesity is a complex condition that occurs when an individual’s weight is higher than what is considered healthy for their height. Many factors can lead to excess weight, including eating habits and patterns and levels of physical activity. Social factors, such as where a person is born, lives, works, and ages; genetics; and certain medications can also play a role. 

Obesity rates have skyrocketed in recent decades, not just among adults but also in children. The disease can be a risk factor for the development of conditions such as diabetes and high cholesterol in childhood, and its prevalence can have a social and economic impact.  

This means obesity is now a public health concern at the global level. The World Obesity Federation predicts that 1 billion people will be living with obesity by 2030, one in every five women and one in every seven men. The greatest ratest of obesity are found in low- and middle-income countries. 

In the United States, the prevalence of obesity among adults has jumped from 30.5% to 41.9% in recent decades. And during the same period, the prevalence of severe obesity increased from 4.7% to 9.2%. Among the country’s Hispanic population, nearly 45% of people are obese, and women are the most affected. 

In Latin America, 24% of the population — about 105 million people — are obese, with the highest rates in Mexico, and Chile (69%, 64%, and 63%, respectively). The rate of obesity in women is 10 percentage points higher than that of men. 

Dozens of behavioral and pharmacological treatments that claim to solve the problem of obesity, some legitimate and others not so much, have emerged in the last few years. Two of the most recent are injections originally developed for patients with diabetes, and not for weight loss. 

These are the drugs Ozempic and Mounjaro, which are backed by solid scientific research but have stirred up controversy.  

Ozempic is a weekly injectable medication for adults with type 2 diabetes that, along with diet and exercise, has been shown to lower blood sugar as well as reduce the risk of serious cardiovascular events such as heart attack, stroke, or death in adults with diagnosed heart conditions. This drug helps the pancreas produce more insulin when blood sugar levels are high. 

Mounjaro, another drug, has a different chemical mechanism but accomplishes the same goal as Ozempic: lowering blood sugar in adults with type 2 diabetes. Like Ozempic, it is administered as a weekly injectable. 

Both drugs also share an added benefit: they can help people reduce the amount of food they consume and lose weight. For this reason, these medications are considered part of a new generation of obesity treatments that some experts are calling a medical milestone. 

Ozempic and Mounjaro for Obesity

Although Ozempic is not specifically labeled for weight loss, scientific studies found that semaglutide, its active ingredient, was successful for weight loss in overweight and obese people. 

In general, a person's weight is considered healthy if their body mass index (BMI) is between 18 and 24.9. If their BMI is between 25 and 30, they are considered overweight; if it is above 30, they are obese. 

In a clinical trial involving 1,961 overweight or obese adults, a 2.4 mg injection of semaglutide once weekly — along with lifestyle interventions like improved diet and increased physical activity — was associated with a sustained and clinically relevant reduction in body weight. 

Faced with this evidence, the United States Food and Drug Administration (FDA) approved semaglutide for weight loss in 2021 under the brand name Wegovy, which provides a higher dose of the active ingredient. 

How does semaglutide work?

As a GLP-1 receptor agonist (an insulin-based drug), semaglutide is believed to impact hunger centers in the brain, specifically the hypothalamus. It works by: 

• Reducing appetite and cravings linked to food; 
• Decreasing the speed with which the stomach empties, prolonging the feeling of satiety after a meal; 
• Reducing food portions. 

Approximately 85% of patients with type 2 diabetes are also overweight. These patients could therefore reap a double benefit with Ozempic, treating their diabetes and losing weight. 

Mounjaro operates similarly to Ozempic, using a different active ingredient, tirzepatide (a peptide or amino acid molecule), which has demonstrated efficacy in reducing body weight by up to 20.9% in clinical trials.  

A clinical trial of Mounjaro involving 2,539 adults with a body mass index of 30 or more, defined as obesity, showed that a weekly dose of tirzepatide led to a significant and consistent weight loss. Researchers also observed improvements in cardiometabolic measures with use of the drug.

Despite this promising data, Ozempic and Mounjaro have limitations on who can use them. Both drugs carry an important warning about the risk of developing thyroid gland tumors.

Other possible side effects include nausea, inflammation of the pancreas (pancreatitis), gallbladder problems (including gallstones), low blood sugar, acute renal failure, diabetic retinopathy (damage to the retina of the eye), and increased heart rate. 

These potential side effects should be discussed with a health care provider in order to make informed decisions based on the risks and benefits of these medications, both for the treatment of diabetes and to reduce weight. 

It is worth remembering that there are no miracle drugs, but rather a combination of treatment and good lifestyle habits to mark the difference between health and disease.   

Remember, always consult with your physician or health care professional to determine the best options for your body and health and to answer any questions you may have regarding any medical matter.