On July 14, the U.S. Food and Drug Administration (“FDA” or the “Agency”) issued a warning letter (the “Warning Letter”) to WHOOP, Inc. (“WHOOP”), rejecting WHOOP’s claim that its wearable “Blood Pressure Insights” product qualifies as an unregulated wellness product[1] and alleging, instead, that the product qualifies as a “device”[2] under the Food, Drug, and Cosmetics Act (“FDCA”) (i.e., is intended for use in the diagnosis, cure, mitigation, prevention, or treatment of a disease or condition).[3] FDA concludes, therefore, that the product is misbranded and adulterated, as WHOOP is currently marketing the product with a cleared 510(k) notification or approved premarket application (“PMA”).
In the Warning Letter, FDA points to evidence that allegedly shows that the product is intended to measure blood pressure, which FDA says is “inherently associated with the diagnosis of hypo- and hypertension:”
- Product claims on WHOOP’s website, which describe the product as providing “daily systolic and diastolic blood pressure estimations, offering members a new way to understand how blood pressure affects their performance and well-being” and “delivering medical-grade health & performance insights;”
- Condition statements on WHOOP’s website, which state that “the impact of blood pressure on sleep, recovery, and performance are not well understood or widely studied” but “[h]igher blood pressure may be an indicator of poor sleep;”
- Product design, which includes green, yellow, and orange color-coding to indicate a target blood pressure range; and
- Other product clearances (i.e., other blood pressure measurements products that don’t explicitly reference hypo- or hypertension in their labeling or otherwise market their products under valid 510(k) clearances).
FDA clarifies that the presence of disclaimers and the fact that the product provides a daily blood pressure range and midpoint measurement instead of a real-time reading are not sufficient to render the product an unregulated wellness product because FDA does not consider the product “low risk.” According to FDA, providing blood pressure measurements is not a low-risk function because “high blood pressure is the most prevalent modifiable risk factor for cardiovascular disease” and “[a]n erroneously low or high blood pressure reading can have significant consequences for the user,” including “stroke, heart attack, heart failure, kidney failure, cognitive decline, and premature death.” As FDA clarifies, the risk is especially heightened for a disease like hypertensions that often presents without physical symptoms.
Notably, FDA issued the Warning Letter only about two months after its first engagement with WHOOP, signaling an apparent increased enforcement urgency in this area, especially for wearable, physiological measurement products that FDA deems high risk. Manufacturers of such products who wish to avoid regulation should take care to design product outputs and draft marketing/labeling claims in alignment with FDA’s guidance and historical enforcement on unregulated wellness products.
Interestingly, however, WHOOP is publicly standing its ground. The day after FDA published the Warning Letter, WHOOP fired back with a press release defending its position that its “Blood Pressure Insights” product is an unregulated wellness product and not a regulated device.[4] Although we haven’t yet heard of a rebuttal by FDA, it will be interesting to see whether the Agency chooses to make an example of WHOOP or, perhaps, diffuse the situation through increased industry education (after all, FDA did just launch its so-called “Regulatory Accelerator” intended to help guide developers of digital health products through the relatively complex regulatory framework). Either way, this is definitely a space to watch.
FOOTNOTES
[1] Under the FDCA, a software function is not a device if it is intended for maintaining or encouraging a healthy lifestyle and is unrelated to the diagnosis, cure, mitigation, prevention, or treatment of a disease or condition. See 21 USC 360j(o); FDA Guidance, General Wellness: Policy for Low Risk Devices.
[2] Specifically, a non-invasive blood pressure measurement system regulated under 21 CFR § 870.1130.
[4] See Press Release, Why WHOOP Stands Behind Blood Pressure Insights, WHOOP, Inc. (July 15, 2025).