The US Food and Drug Administration (FDA) has published a warning letter addressed to the blood-pressure-tracking and wrist-wearable company Whoop, alleging it is marketing its new blood pressure feature without first getting proper approvals.

The FDA said Whoop’s Blood Pressure Insights (BPI) feature is intended to diagnose, cure, treat or prevent disease – a key distinction that would reclassify the wellness tracker as a “medical device” that has to undergo a rigorous testing and approval processes.

For its part, in a letter dated June 2, 2025, Whoop described the purpose of its BPI feature, how it works, and why it believes it is not a medical device subject to FDA regulatory authority. It said it uses blood pressure information to mainly offer performance and wellness insights that inform consumers and improve athletic performance.

Whoop told the FDA it believed its BPI falls under an exemption from the definition of “device” software functions that applies to devices intended for maintaining or encouraging a healthy lifestyle – purposes that are unrelated to the diagnosis, cure, mitigation, prevention, or treatment of a disease or condition.

Device use

The analysis here swings on the device’s intended use, as noted above. More specifically, the FDA analyzes what a device’s intended use is based on: (1) the objective intent of the persons responsible for its labeling; (2) the wording used by those persons to describe it; (2) the design or composition of the article; or (3) the circumstances surrounding its distribution.

“Providing blood pressure estimation is not a low-risk function.”

FDA, in its warning letter to Whoop

The FDA said that, based on FDA’s evaluation of BPI’s intended use, the product is intended to provide a measurement or estimation of a user’s blood pressure, which is inherently associated with the diagnosis of hypo- and hypertension.

This means it is intended for use in the diagnosis of a disease or other condition, or in the cure, mitigation, treatment, or prevention of disease, the FDA said.

“This conclusion is bolstered by both your firm’s [Whoop’s] statements about BPI (eg, “Higher blood pressure may be an indicator of poor sleep.” [emphasis added by the FDA]) and BPI’s design, which outputs a blood pressure measurement to users and provides the reading on a gauge that uses green, yellow, and orange color-coding to indicate a target blood pressure range.”

The FDA said in the letter: “Providing blood pressure estimation is not a low-risk function. An erroneously low or high blood pressure reading can have significant consequences for the user.”

And the regulator said that although BPI provides a daily blood pressure range and midpoint measurement instead of a real-time reading, that is not sufficient to distinguish the product’s intended use from other blood pressure measurement devices.

This is “because a blood pressure range or midpoint estimation, like a real-time reading, is inherently associated with the diagnosis of hypo- and hypertension,” the FDA said.

Whoop pushes back

A Whoop spokesperson told news outlets the company’s system offers only a single daily estimated range and midpoint, which distinguishes it from medical blood pressure devices used for diagnosis or management of high blood pressure.

The spokesperson said the BPI data is not unlike other wellness metrics that the company deals with in its other wearables. Just as heart rate variability and respiratory rate can have medical uses, the spokesperson said, they are permitted in a wellness context too.

“We believe the agency is overstepping its authority in this case by attempting to regulate a non-medical wellness feature as a medical device,” the Whoop spokesperson added.

Wearables

In addition to helping wearers appreciate their blood pressure fluctuations, Whoop has devices to help customers track their stages of sleep and understand their sleep needs; to better understand hormonal changes, like pregnancy; and get a snapshot of their heart’s electrical activity.

Regulatory compliance issues abound here, with some risk concerns over data privacy (staying in compliance with the UK’s GDPR and HIPAA in the US), safety standards involving electrical and electromagnetic issues; and third-party risks with any interconnected data users, in addition to the intended use ones noted above.

Using anything to track, diagnose or treat a disease is strictly regulated by the FDA as well as regulators in other countries.

In addition, there is ISO 13485, known as a gold standard for medical device quality systems and designed to establish benchmarks for ensuring design safety, help prepare for inspections, and create better regulatory submissions.

For any company offering the devices, it is crucial to build compliance into the business’s process to nail down if the design features and communications around the device are considered “medical” or “wellness.”