Blood pressure monitoring as health feature, not medical device—Whoop won the FDA fight
Whoop classified blood pressure as a health function, withstood FDA's warning letter, got the agency to revise its guidance, and kept the feature live.
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High retention, not hardware sales, saved the company
When Whoop launched at $500 per device in 2017, a year of data showed two things: users who bought wore the device long-term—rare for wearables—but few consumers would pay $500 upfront. The team dropped entry prices and shifted to subscription, letting more people try before committing. Between 2018 and 2019, this strategy drove growth and transformed the business from hardware sales to recurring revenue.
— Will AhmedSubscriptions inverted the upgrade cycle incentive
Hardware-only companies face an incentive to release new models every 12 months regardless of innovation, because each sale funds the next, and older devices can't gain features without killing new-device sales. Subscriptions flip this: Whoop releases a new generation only when hardware fundamentally improves, while continuously pushing new capabilities to devices already in the field—ECG, atrial fibrillation detection, blood testing, HealthSpan, and blood pressure insights all rolled out as software updates to existing users.
— Will AhmedTwo extra breaths per minute sent him to the ER
Jason shared a personal story: one day his respiratory rate jumped from a normal 16 to 17–18 breaths per minute, skin temperature rose 2 degrees, and the pattern repeated for two straight days. Sunday night, chest pain arrived. At the cardiac center, CT and EKG revealed inflammation around his lungs and chest cavity, compressing the heart—not a heart attack. Three years earlier, the same pattern—elevated skin temperature and HRV anomalies—had warned him of COVID infection before symptoms emerged.
— Jason CalacanisAbnormal heart rate revealed stage-four lymphoma and testicular cancer
Will shared two user cases. A healthy baseball player with a baseline resting heart rate of 50 once saw his heart rate spike to 120–130 during sleep; he was diagnosed with stage IV Hodgkin lymphoma and recovered after treatment. Another user who had worn Whoop for nearly a decade with a stable HRV baseline of 100 saw it suddenly drop to 50 and stay there; testing revealed testicular cancer. Will acknowledged that this kind of disease signal reverse-engineered from physiology wasn't familiar to medicine at the time.
— Will AhmedWhoop trains AI on its own data rather than selling it
When asked whether AI companies wanted to buy the 50-billion-hour dataset, Will said Whoop chose to train its own foundation model on the data rather than sell it. As users uploaded blood tests, physical exams, and medical records, the team began observing that certain biomarker abnormalities—such as cortisol levels—could be predicted from physiology alone without direct measurement, giving users a concrete recommendation: go get this tested.
— Will AhmedBlood pressure as health feature won the FDA fight
Four years ago, Whoop wanted to offer wristband blood pressure monitoring without a cuff. The company collected data from 70,000 participants in a stress-sleep-blood pressure study to train the algorithm. Historically, FDA classified all blood pressure monitoring as a medical device requiring approval—unlike heart rate monitoring for fitness, which is a health function. Whoop argued that blood pressure is tightly linked to stress and sleep, treated it as a health feature, and launched. FDA sent a warning letter; the two sides clashed publicly. Ultimately, FDA updated its guidance, and Blood Pressure Insights remains a health feature in the product today; ECG took a separate 510(k) clinical pathway and earned formal medical device approval.
— Will AhmedThe member, not the data, is the product
When suggested that Whoop should make its own blood pressure cuffs and scales, Will redirected to business model. The company maintains strict data policies and does not sell user data. "You are not the product. Membership is the product." He viewed this as the key differentiator from ad-driven Big Tech companies and the foundation of user trust when sharing blood tests, medical records, and GLP-1 medication information.
— Will AhmedLeBron's endorsement proved organic use beats paid marketing
Whoop announced LeBron James as global ambassador, but he had already worn Whoop for 11 years as one of the first 100 users—with no formal relationship beforehand. Will explained the early-stage policy: never pay athletes to wear the device, because it must be worn 24/7 and no payment can change that if they don't genuinely like it. Only when a product truly works and athletes use it organically does it lead to formal endorsement deals. This echoes disputes over whether wearables are allowed in competition; the Australian Open once required players to remove Whoop.
— Will AhmedIn their own words · checked verbatim
On average, a Whoop member wears Whoop 23.6 hours a day. We have just over 50 billion hours of continuous physiological data. So it's one of the largest health data sets in the world.
Will Ahmed0:00
for a dollar a day, I think this is like one of the best things you could spend on your health
Will Ahmed3:01
when you're a subscription business, you become really obsessed with your existing members, arguably more so even the new members
Will Ahmed4:02
Someone with a resting heart rate of 50 beats per minute, getting a heart rate of 120, 130 while he's sleeping. And he goes in to see the doctor and they do some tests. And sure enough, stage four Hodgkin lymphoma.
Will Ahmed13:28
there's an avalanche of research that supports that. Not surprisingly, blood pressure affects your stress. It affects your sleep. It affects your overall well-being.
Will Ahmed39:23
So we do not sell data. You know, you are not the product, Jason, like you're, the membership is the product.
Will Ahmed42:29
there's no amount of money I'm going to be able to pay an athlete to wear something 24-7 if they don't like it.
Will Ahmed49:39
Figures
| Whoop members | ~4 million expected by year-end | 2:01 |
| Total physiological data | Over 50 billion hours | 0:00 |
| Average daily wear time | 23.6 hours | 0:00 |
| Monthly subscription | $15–$30/month | 2:01 |
| Employees | 1,200 | 25:57 |
| Jason's GLP-1 weight loss | 43 pounds (from 213 to 170 pounds) | 32:04 |
| Fat-to-muscle ratio in GLP-1 weight loss | Approximately half fat, half muscle | 33:04 |
| LeBron James' Whoop usage | 11 years, one of the first 100 users | 47:34 |
Glossary
- HRV
- Heart rate variability—fluctuation between consecutive heartbeats; higher values typically signal healthier autonomic nervous system regulation.
- GLP-1
- GLP-1 receptor agonist—a class of weight-loss and blood sugar control medications, including semaglutide.
- AFib
- Atrial fibrillation—an irregular heart rhythm requiring accurate detection by medical devices.
- 510(k)
- 510(k) pathway—a streamlined FDA approval route for medical devices.
- ICP
- Ideal customer profile—the target user archetype best suited to a product.
How to listen
Entrepreneurs and product managers interested in hardware-to-subscription transitions, medical device regulatory boundaries, or personal health data products.
The final segment about early-stage venture SPV transactions is tangential to Whoop and can be skipped.