Why I love Lumen

Lumen: A Small Device With Big Potential for Heart & Metabolic Health

If you’ve been following along with my journey into prevention and integrative cardiology, you know I’m always on the lookout for tools that can help us better understand our bodies. One device that has really caught my attention—and that I’ve been personally experimenting with—is Lumen.

What Is Lumen?

Lumen is a handheld, at-home metabolic tracker. With just a single breath into the device, it measures the concentration of CO₂ and determines whether your body is primarily burning carbohydrates or fat for fuel. Think of it as a real-time snapshot of your metabolism. Traditionally, you’d need a lab-based metabolic cart (big, expensive, and not exactly user-friendly) to get this kind of insight. Lumen makes it accessible in minutes, right from home.

Why I Like It

As a cardiologist, I see every day how much metabolism drives heart health. Insulin resistance, obesity, diabetes, and even blood pressure are all linked to how our bodies process energy. What I appreciate about Lumen is that it gives immediate, personalized feedback. Instead of just telling patients “eat better” or “exercise more,” it allows us to track how daily choices—like meals, sleep, or stress—shift metabolism in real time.

For me personally, it’s been eye-opening to see how a night of poor sleep or a stressful day shows up in my Lumen scores. It helps connect the dots between lifestyle and physiology in a way that’s motivating and actionable.

How It Can Be Helpful

• Personalized nutrition guidance: By showing whether you’re burning carbs or fat, Lumen helps tailor meal timing, macronutrient balance, and exercise fueling strategies.

• Metabolic flexibility training: The ability to switch between carb and fat metabolism is key for long-term health. Tracking it daily gives you a roadmap for improvement.

• Accountability & habit-building: Sometimes we need feedback beyond the scale or blood tests. Seeing day-to-day metabolic responses reinforces healthy behaviors.

• Prevention & heart health: While not a replacement for traditional medical testing, Lumen can be a practical tool for those at risk of diabetes, obesity, or cardiovascular disease to better understand how lifestyle impacts their body.

The Bottom Line

I like to think of Lumen as a bridge between the clinical world and the day-to-day choices that shape our health. It doesn’t replace your doctor, labs, or medical tests—but it does give you a new lens into how your body works. And for many of my patients (and myself), that kind of insight can make all the difference.