LEVELS HEALTH

Josh Clemente was a SpaceX engineer obsessed with performance. He'd spent years optimizing rockets and thought: why can't I do the same thing for my own body?

He started researching continuous glucose monitors — CGMs — devices that diabetics wear to track blood sugar in real time. What he found stunned him.

He'd eat what he thought was a healthy meal and his glucose would spike into the danger zone. Nobody was telling him this.

There was no app for it. There was barely any awareness that non-diabetics should even care.

In 2019, he pulled together a small group: Sam Corcos, a serial founder; David Flinner, a designer; Andrew Conner, an engineer; and his sister Mercy. They weren't a typical startup team — they were people who genuinely believed metabolic health was the most underdiagnosed crisis in modern medicine.

They started by writing. Publicly.

The Levels blog became one of the most respected sources of information on metabolic health before the product even existed.

They launched a waitlist in early 2020. No product.

No shipping date. Just the idea and the blog.

Within months, 100,000 people had signed up. Peter Attia was talking about them.

Health podcasts were recommending them. They had demonstrated product-market fit without a product.

That almost never happens.

Here's the simple version: Levels pairs a continuous glucose monitor — a small sensor you stick on your arm — with a mobile app that tells you what your glucose data actually means. CGMs have existed for years, but they were designed for diabetics and their interfaces looked like it.

Levels made them beautiful, contextual, and actionable for people who have never been diagnosed with anything.

Customers pay a membership fee — currently around $199 to $399 per month depending on the plan — which covers the CGM hardware (typically Abbott's FreeStyle Libre or Dexcom sensors), the Levels app, and the data analysis layer that turns raw glucose readings into insights. You scan your arm with your phone, see your glucose level in real time, log a meal, and the app tells you how your body responded.

Spike too high? That food might not be right for you.

Flat and steady? Good sign.

Levels also operates a telehealth layer — in most US states, a CGM requires a prescription, so Levels connects users with physicians who can authorize the device. It's a full-stack model: prescription, hardware, software, and interpretation, all in one subscription.

The bet is that people will pay a premium not just for data but for understanding. So far, the people who try it tend to stay.

The core product is the Levels app paired with a continuous glucose monitor. You wear a small circular sensor on the back of your upper arm.

It reads your interstitial glucose every few minutes. You scan it with your iPhone and see your glucose level, trends, and history.

Log a meal and the app scores it — showing you how your blood sugar responded and what that means for your metabolic health. It sounds simple because it is.

The complexity is in the interpretation layer.

Levels also offers a Metabolic Fitness Score — a proprietary metric that aggregates your glucose behavior over time into a single number. Think of it like a credit score for your metabolism.

It accounts for how high your glucose goes, how long it stays elevated, and how stable it is day to day. Users track it like a KPI for their body.

More recently, Levels has expanded beyond glucose into a broader metabolic health platform. They've added integrations with other wearables — Oura Ring, Apple Watch — to layer in sleep data, heart rate variability, and activity context alongside glucose.

The goal is to move from 'glucose monitor with an app' to 'the operating system for your metabolic health.' Whether that ambition holds together as a product remains to be seen, but the direction is clear.

The blog came first. That's the move almost no health startup makes, and it's the reason Levels has a brand that most well-funded competitors don't.

Before Josh Clemente and Sam Corcos shipped anything, they were publishing long-form, research-backed content on metabolic health, insulin resistance, and glucose monitoring. Real science.

Not listicles. The kind of writing that got shared by doctors, cited by researchers, and bookmarked by the exact kind of curious, health-obsessed person who would eventually pay $300 a month for a CGM subscription.

Then came the waitlist. 100,000 people before launch.

That number is not an accident — it's the result of years of content building trust with exactly the right audience. When they finally started shipping, they had a queue of people who already believed in the product.

From there, word of mouth did the work. Levels became the thing every biohacker, longevity nerd, and performance-obsessed executive talked about.

Peter Attia — arguably the most influential longevity doctor in the world — was an early advocate and investor. Andrew Huberman covered it.

Tim Ferriss wore one. The kind of earned media that money can't buy, because it came from genuine product love from people whose audiences trust them completely.

They also built in public — sharing fundraising memos, internal documents, and company metrics in a way almost no startup does. It made them a case study in transparent building and attracted both customers and investors who wanted to be part of something different.

The CGM market is about to get very crowded very fast. Abbott and Dexcom — the two giants who make the actual sensors Levels depends on — both launched their own over-the-counter CGM products in 2024.

Abbott's Lingo and Dexcom's Stelo are aimed directly at the wellness consumer Levels built its entire business around. Levels is essentially building on top of hardware it doesn't control, from companies that are now its direct competitors.

That's not a comfortable position.

There's also the question of whether the core thesis scales beyond the early adopter. The people who currently pay $200–400 per month for continuous glucose monitoring are already health-obsessed, already comfortable with wearables, and already convinced that metabolic data matters.

Convincing the average person — who barely thinks about blood sugar unless they're diabetic — is a much harder and more expensive problem.

And the clinical question hasn't been fully settled. Critics, including some endocrinologists, argue that for metabolically healthy people, glucose monitoring creates anxiety without actionable benefit.

The data on whether CGM-guided behavior changes actually improve long-term health outcomes in non-diabetics is still thin. If that research goes the wrong way, Levels' entire value proposition gets harder to defend.

Levels raised $38 million in a Series A led by Andreessen Horowitz in 2021 — a16z's bio fund, specifically, which meant they had backing from people who understood both the science and the scale of the opportunity. That round also included participation from Sam Altman, Kevin Rose, and a cohort of angel investors who were, frankly, also the target customers.

Peter Attia invested. Balaji Srinivasan invested.

These aren't just names on a cap table — they're the people whose endorsement makes a health product credible to the exact demographic Levels is targeting.

The total raise of approximately $75 million across rounds puts Levels in a well-capitalized position for a company still in private beta for much of its life. The investors brought more than money — they brought reach.

When Peter Attia talks about Levels on his podcast to 1.5 million health-obsessed listeners, that's distribution no ad budget can replicate. The investor list is essentially a curated list of the most influential people in longevity and performance health.