There is a lot of research behind the GLP-1 drugs
Present-day weight loss pills are known as GLP-1 agonists, which is because they are mimicking the hormone GLP-1 (glucagon-like peptide-1). This hormone was discovered in the 1980s and researchers found out that it enhanced insulin secretion and slowed gastric emptying, which made it interesting for diabetes and obesity treatment.
A few decades of research later, in 2005, the first FDA-approved GLP-1 drug, exenatide (Byetta), was on the market for the treatment of type 2 diabetes. But it wasn’t until 2017 when Semaglutide (Ozempic) was approved by the FDA that this class of drugs became popular. That’s because Ozempic can be administered only once weekly, offering convenience and improved adherence for patients.
How do obesity medicines work?
To understand these weight loss drugs, it helps to see how they affect the body and mind when it comes to food. By mimicking the function of GLP-1, they are able to produce three effects:
• They trigger insulin secretion in the pancreas, which helps regulate blood sugar and also helps you feel full after a meal.
• They slow gastric emptying, how fast foods travel in your gut, which, again, helps you feel full for longer after eating.
• They affect the brain to reduce food cravings and food noise – intrusive thoughts about food.
All of these three things also happen to all of us thanks to the natural production of the GLP-1 hormone. The thing is, in people with obesity, the body quickly breaks down its own GLP-1, which makes it less effective. As a result, it takes them longer to feel full, they get hungry quicker and experience almost constant food noise. Drugs like Ozempic give the body a synthetic GLP-1 hormone that lasts much longer and compensates for these obstacles obese people experience.
How effective are GLP-1 drugs?
Research shows that about 86% of overweight or obese people who take GLP-1 drugs like Ozempic, Wegovy or Rybelsus lose at least 5% of their body weight. And about 33% of them lose more than 20% of their body weight. Newer generation versions of these medications such as tirzepatide are even more promising. Studies show that up to 57% of people using those medications lose more than 20% of their body weight.
Weight loss drugs compared to lifestyle changes
With lifestyle changes and coaching, on average, people lose about 5-13% of their body weight. This is pretty impressive considering there are no drugs or side effects involved. But to simply compare these numbers to the percentages we see in weight loss drugs research would be a mistake. That’s because lifestyle interventions and weight loss drugs combined typically produce 10% extra body weight loss.
New research promises even more efficacy with fewer side effects
Research on weight loss drugs is not slowing down. In fact, a recent study identified a melanocortin-3 receptor (MC3R) in the brain that when inhibited, can improve the responsiveness to GLP-1 agonists. Initial tests on mice indicate that pairing GLP-1 drugs with MC3R antagonists could increase sensitivity to the desired effects of the drugs by up to 5x, without increasing unwanted side effects. This could help patients who are sensitive to the side effects of GLP-1 drugs to take a significantly lower dose while getting much better results.
To summarise, the current generation of weight loss drugs is very effective and results in significant weight loss, especially when paired with lifestyle interventions. Research promises further improvements. Some people call weight loss drugs cheating for this reason. Let’s take a look at that in the next article.
