The Truth About Obesity, Ozempic/GLP-1s and Dieting with Dr. Karl Nadolsky

Why Weight Loss is More Than Willpower, According to an Endocrinologist

In a recent episode of the Modrn Wellness podcast, I sat down with endocrinologist Dr. Karl Nadolsky to unpack the medical reality of obesity, the role of GLP-1 medications, and the truth behind common weight loss myths.

Dr. Karl Nadolsky is a board-certified endocrinologist and obesity specialist who’s dedicated his career to shifting the narrative around weight and metabolic health. With a focus on evidence-based, compassionate care, he helps patients understand the true drivers of obesity - from hormones and inflammation to stress, sleep, and beyond.

In this episode, Dr. Mary Pardee from Modrn Wellness Podcast and Dr. Karl Nadolsky unpack the science behind weight gain and fat loss, exposing the flawed narratives around obesity that lurk on social media.

Whether you’re trying to lose weight, support your metabolism, or better understand your body, this conversation helps reframe the way we talk about weight.

Obesity Is a Chronic Disease, Not a Character Flaw

One of the biggest takeaways? Obesity meets the clinical criteria of a disease.

“Obesity is the disease of excess adiposity that we can diagnose and causes harm, or at least potentially causes harm.” — Dr. Karl Nadolsky

Yes, lifestyle factors play a role. But Dr. Nadolsky points out that the disease often begins with genetics—what he calls “loading the gun”—and is triggered by an environment full of hyper-palatable, calorically dense foods.

Not All Fat Is Bad: The Role of “Healthy Fat”

Contrary to popular belief, not all body fat is harmful.

There’s a difference between peripheral fat cells, which are metabolically healthy, and visceral fat stored around the organs, which increases risk for type 2 diabetes, fatty liver, and heart disease.

What Patients Struggle With: The Real Enemy Is “Food Noise”

One of the most validating parts of our conversation was Dr. Nadolsky’s description of what people actually feel when they struggle with obesity. It's not just about hunger—it’s a constant mental loop.

“Some people say, ‘I just think about food all the time.’ That’s what they now call food noise.” — Dr. Karl Nadolsky

GLP-1 medications like semaglutide and tirzepatide can help quiet this noise, which many patients describe as life-changing.

Muscle Loss on GLP-1s: Real Concern or Misinformation?

Some influencers claim that GLP-1 medications cause extreme muscle loss. Dr. Nadolsky pushes back hard on this.

“Everybody who loses weight loses some lean mass. That’s true for diet, exercise, medications, or surgery.” — Dr. Karl Nadolsky

He emphasizes that strength training and adequate protein intake are key for preserving muscle, regardless of how the weight is lost.

Comparing Weight Loss: Lifestyle vs. Medications

Let’s talk numbers. In clinical trials, diet and exercise alone usually result in about 2–8% total weight loss. Compare that to:

• Semaglutide: ~15% average weight loss

• Tirzepatide: ~20%, with some patients reaching 25%+

• Liraglutide: ~6-7% average weight loss

• Phentermine/Topiramate: ~10–12%

• Naltrexone/Bupropion: ~5–8%

“When 40% of people on semaglutide achieve 20% weight loss...this is when we see dramtic [health] improvements” — Dr. Karl Nadolsky

Health improvements from 20% of weightloss can include:

• remission from sleep apnea

• remission of steatohepatitis (fibrosis of the liver)

• improved insulin sensitivity

• blood pressure reduction

• reduced rates of heart disease

• improvements in joint pain

• more

Should Everyone Be on GLP-1s?

No. Dr. Nadolsky is careful to match the treatment to the severity of disease. For example, patients with type 2 diabetes and heart disease benefit the most.

But what about those who are just 10–15 pounds above their goal weight?

“I wouldn’t take it just for a little cosmetic change… It’s still medicine. You’re taking drugs that you don’t really need for your health.” — Dr. Karl Nadolsky

Is It Forever? The Durability Question

These medications aren’t meant to be “quick fixes.” They treat a chronic disease—so often, they’re needed long-term.

“I don’t want you to stop, come back in a year, and all the weight is back with high blood sugar and complications.” — Dr. Karl Nadolsky

That said, some patients can transition to lower doses or other medications for maintenance.

The Problem with Compounded GLP-1s

If you’re tempted by cheaper compounded semaglutide or tirzepatide, Dr. Nadolsky has a strong warning:

“The compounding pharmacies didn’t do the research. They don’t have the regulated molecular production facilities. I wouldn’t take it. I wouldn’t trust it.” — Dr. Karl Nadolsky

Final Thoughts

Whether you’re a provider or someone navigating your own weight journey, one thing is clear: Obesity is not a failure of willpower. It’s a complex, chronic disease that deserves medical recognition, evidence-based treatments, and compassionate care.

“It’s what’s on the inside that counts. We’re treating for health, not just for a number on the scale.” — Dr. Karl Nadolsky

For more evidence-based health insights and myth-busting content, subscribe to the Modrn Wellness podcast and follow @dr.marypardee on Instagram.

Follow Dr. Karl Nadolsky

Instagram: @drkarlnadolsky

Podcast: DocsWhoLift

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