Semaglutide for Weight Loss: How Ozempic and Wegovy Really Work

When you hear about people losing 30, 40, even 50 pounds on a medication, it’s hard not to wonder: is this real? And if it is, how does it actually work? Semaglutide - sold as Ozempic for diabetes and Wegovy for weight loss - isn’t just another diet pill. It’s changing how we think about obesity treatment. But it’s not magic. And it’s not for everyone.

What Semaglutide Actually Does in Your Body

Semaglutide mimics a natural hormone your body already makes called GLP-1. This hormone talks to your brain, your stomach, and your pancreas. When you eat, GLP-1 tells your brain you’re full. It slows down how fast your stomach empties. And it helps your pancreas release insulin only when you need it - not when you don’t.

That’s the key. Most weight loss drugs just suppress appetite. Semaglutide does that, but it also changes how your body handles food. You don’t just eat less. You care less about food. People on Wegovy often say, ‘I used to crave chips, cookies, pizza. Now, I just don’t feel that pull anymore.’

Studies show this isn’t just in their heads. In the STEP 1 trial, people using Wegovy lost nearly 15% of their body weight on average over 68 weeks. That’s not a few pounds. That’s 30 to 50 pounds for most people. Compare that to placebo - they lost about 2.4%. The difference? More than 12 percentage points. That’s huge.

Ozempic vs. Wegovy: Same Drug, Different Doses

Yes, Ozempic and Wegovy are the same molecule: semaglutide. The difference is the dose and the purpose.

Ozempic is approved for type 2 diabetes. It’s given in doses up to 1 mg per week. Wegovy is approved for weight loss and is given at 2.4 mg per week - more than double the dose. That higher dose is what pushes the appetite suppression and weight loss further.

People often ask: ‘Can I just use Ozempic for weight loss?’ Technically, yes - some doctors prescribe it off-label. But Wegovy is formulated specifically for weight management. It comes with a dosing schedule designed to reduce side effects and maximize results. Using Ozempic at higher doses without medical supervision can be risky.

Also, insurance treats them differently. Ozempic is often covered for diabetes. Wegovy? Not always. Many insurers require proof of obesity-related health issues like high blood pressure or prediabetes before they’ll pay.

How Effective Is It Really?

The numbers speak for themselves. In the STEP 1 trial:

• 79% of people lost at least 10% of their body weight
• 69% lost 15% or more
• 50% lost 20% or more

That’s more effective than any other weight loss drug approved in the last 20 years. Liraglutide (Saxenda), the previous gold standard, only helped people lose about 8% on average. Semaglutide nearly doubles that.

And it’s not just about the scale. People report better sleep, less joint pain, improved blood pressure, and more energy. One woman in Melbourne told her doctor, ‘I haven’t walked to the mailbox in years. Now I do it every morning.’ That kind of change matters.

The Catch: Side Effects and Weight Regain

There’s no free lunch. About 77% of people on Wegovy experience nausea. Around 64% get diarrhea. About half vomit at least once during the first few months. These aren’t mild. They can be debilitating.

The good news? Most side effects fade as your body adjusts. That’s why the dosing starts low - 0.25 mg per week - and creeps up over 16 to 20 weeks. Rushing the dose increase makes side effects worse.

But the bigger problem? Weight regain. When people stop taking semaglutide, they typically regain two-thirds of the weight they lost within a year. That’s not failure. That’s biology. Your body fights to return to its old set point. Semaglutide doesn’t reset that. It just helps you manage it.

This is why experts say it’s not a cure. It’s a tool. Like insulin for diabetes, you may need it long-term. The STEP 4 trial showed that people who stayed on Wegovy kept 10.6% of their weight off after 68 weeks. Those switched to placebo gained back nearly 7%.

Who Should Use It - And Who Shouldn’t

Semaglutide is FDA-approved for adults with:

• Obesity (BMI ≥30)
• Overweight (BMI ≥27) with at least one weight-related condition - like high blood pressure, high cholesterol, or prediabetes

It’s also approved to reduce heart attack and stroke risk in people with existing heart disease and obesity - a major win.

But it’s not for everyone. You shouldn’t use it if you have:

• A personal or family history of medullary thyroid cancer
• Multiple Endocrine Neoplasia Syndrome Type 2

These are rare, but serious. The drug caused thyroid tumors in rats. No proven link in humans - but the risk isn’t zero. Doctors screen for this before prescribing.

Also, if you’re pregnant, breastfeeding, or planning to get pregnant, avoid it. There’s not enough safety data yet.

The Cost and Access Crisis

In the U.S., Wegovy costs about $1,350 a month. That’s not affordable for most people without insurance. Even with insurance, many plans require prior authorization, step therapy, or deny coverage entirely.

Supply shortages are another issue. In late 2023, 78% of U.S. providers reported patients couldn’t get their prescribed dose. Some wait months. Others switch to Ozempic - which is cheaper and more available - but that’s not always safe or legal.

Here in Australia, the situation is different. Wegovy isn’t yet listed on the Pharmaceutical Benefits Scheme (PBS). That means patients pay full price - around AUD $1,600 per month. Most can’t afford it. Some travel to the U.S. or use online pharmacies. Both carry risks.

Novo Nordisk offers a patient assistance program in the U.S. for uninsured people. In Australia, there’s no equivalent. That creates a huge equity gap. Weight loss isn’t a luxury. It’s a medical need.

What Works Best Alongside Semaglutide

Studies show semaglutide works best when paired with lifestyle changes. In the STEP trials, everyone got weekly counseling on diet and exercise. They didn’t just get a shot - they got support.

Here’s what actually helps:

• Protein-rich meals - they keep you full longer
• Avoiding ultra-processed foods - sugar and refined carbs spike hunger
• Walking 30 minutes a day - even if it’s just around the block
• Sleeping 7+ hours - poor sleep increases ghrelin, the hunger hormone

One man in Melbourne lost 42 pounds on Wegovy. He says, ‘The medication made it possible. But I had to change how I ate. I stopped drinking soda. I started cooking. That’s what kept the weight off.’

It’s not about starving yourself. It’s about eating differently. Semaglutide helps you want less junk. You still have to choose the right food.

The Future: What’s Next?

Researchers are already looking beyond semaglutide. Tirzepatide (Zepbound) - a dual GLP-1 and GIP agonist - is showing even better results: up to 21% weight loss in trials. Oral semaglutide (Rybelsus) is approved for diabetes, and trials for weight loss are underway. If it works, it could be a game-changer - no needles needed.

But the big question remains: Can we afford this? The global market for GLP-1 drugs hit $18 billion in 2023. Experts warn that if millions need lifelong treatment, healthcare systems could be overwhelmed. By 2030, some estimate these drugs could cost the U.S. healthcare system 1-2% of its total budget.

That’s why access, affordability, and long-term support are just as important as the science. A pill that works is useless if no one can get it.

Final Thoughts

Semaglutide isn’t a miracle. But it’s the most powerful weight loss tool we’ve had in decades. It works. It’s backed by hard data. It changes lives.

But it’s not a quick fix. It’s a long-term commitment. It requires medical supervision. It comes with side effects. And if you stop, you’ll likely regain weight.

If you’re considering it, talk to a doctor who specializes in obesity medicine. Don’t rush. Don’t self-prescribe. Don’t believe the hype on social media. This is medicine. Treat it like it.

For many, it’s not about looking better. It’s about living longer. About walking without pain. About not being afraid to get on a scale. That’s worth more than any number on a label.