Understanding semaglutides: Are they the right choice for weight loss?

Semaglutides, marketed under names such as Ozempic^® and Wegovy^®, have made their way to your local pharmacy. These drugs aren’t just for celebrities anymore—more and more people are turning to the medication and others like it to help them lose weight.

But what are semaglutides, and how do they work? Are they really a silver bullet for weight loss? And how can you tell if weight loss medication will work for you?

The diabetes drugs that are changing how we diet

Let’s start with the basics. Semaglutides are a once-weekly injection prescribed to treat adults with type 2 diabetes.¹ You read that right: It wasn’t originally designed as a weight loss drug at all.

Is semaglutide the same as drugs like Ozempic?

How do semaglutides help you lose weight?

Remember, GLP-1 RAs were designed to treat type 2 diabetes. Weight loss began as a side effect because the drug convinces your brain that you’re full more quickly and for longer periods of time than usual. This side effect helped the drug soar in popularity, even though Ozempic hasn’t been approved by the FDA for weight loss.¹ Some doctors prescribe it off-label for patients looking to lose weight. However, the FDA has approved a similar semaglutide injection for weight loss: Wegovy.³

Even though many aren’t approved as weight loss drugs, semaglutides have proven weight loss effects. In fact, some studies found that semaglutides helped people lose an average of 9%-17% of their body weight in a little over a year.⁴

The side effects of semaglutides

So, what’s the catch? Some people using semaglutides have reported side effects. The most common include nausea, vomiting, diarrhea, abdominal pain, and constipation. A few more serious side effects, like pancreatitis and thyroid C-cell tumors, did appear in some trials, but more testing is needed.¹

If you start taking semaglutides, you’ll also need to be mindful of how they may interact with other medications. GLP-1 RAs can slow how your body absorbs other drugs. Researchers are still looking into whether this means certain oral medications won’t be as effective.¹ Make sure to review your medications with your doctor before taking semaglutides.

More to learn about the effects of semaglutides

Science is still learning about how semaglutides affect the body, including how they may impact the way you respond to food. A 2020 study found that people taking semaglutides reported a lower preference for high-fat foods.⁵ A 2024 study suggests that semaglutides may lower your cravings for sweet foods by improving taste sensitivity, changing the gene expression on your tongue that’s responsible for taste perception, and even changing the way your brain responds to sweet tastes.⁶

Do you need lab testing while on semaglutides?

Testing can monitor potential side effects and measure how your weight loss is reducing your chronic disease risk over time. Testing looks at biomarkers associated with thyroid, heart, kidney, and liver health, along with your diabetes risk, and measures how these levels change as you lose weight. Talk to your doctor about the following tests:

Life after weight loss medications

Despite their effectiveness, only about a third of people prescribed semaglutides stay on the drugs for more than a year.⁷ The side effects contribute to that number, but they aren’t the only issue. Semaglutides are expensive: the drugs can cost around $1,000 per month, and they are not always covered by health insurance.⁸ Even if you can afford treatment, getting the drugs is another story. Because of their popularity, many semaglutides like Ozempic and Wegovy are experiencing supply shortages.⁹

Will semaglutides work for you?

Most people who take semaglutides lose weight. But the drugs aren’t effective for about 14% of people who try them.¹¹ For these people, that’s a lot of wasted time and expense (not to mention the discomfort of any side effects) for a drug that doesn’t work.

What if there were a better way to tell if weight loss medication was going to work for you without the trial and error? That’s where researchers hope precision medicine will one day be able to help.

Researchers are currently trying to pin down the biomarker signatures that indicate if a person will respond well to GLP-1 RAs.¹² Once they identify such factors, testing will be able to tell you if you have these biomarkers. If you do, these medications will be more likely to work for you. If you don’t, you and your doctor can look for other ways of helping you lose weight.

If you're intrigued by what weight loss medication could mean for you, the best path forward is to talk to your doctor. Together, you can create a plan of action to help you reach and maintain a healthy weight.