A major expansion of real-world health data
The U.S. research ecosystem gained a notable new data resource this week with the publication of the All of Us Research Program’s wearables dataset in Nature Medicine. According to the paper, the dataset contains Fitbit data from more than 59,000 participants spanning 14 years, including more than 39 million step observations and 31 million sleep observations. Nearly half of the participants with Fitbit data also contributed electronic health records, physical measurements, genomics, and survey data.
That combination makes the release more than a large collection of consumer-device readouts. It creates a multimodal dataset that can potentially connect everyday behavioral and physiological signals to clinical outcomes, demographic context, and molecular data. For researchers studying digital biomarkers, sleep, exercise, chronic disease risk, and population health, the scope is significant.
Why this dataset matters
Wearables have long been seen as a way to move medical research beyond snapshots taken during clinic visits. Devices can capture continuous, real-world information about movement, sleep, and behavior over time. But many wearable datasets have a major weakness: they are often biased toward populations already more likely to buy and use such devices, typically wealthier and less diverse groups.
The All of Us paper explicitly addresses that problem. The authors frame the resource as one of the largest and most demographically rich digital health technology datasets assembled so far. The program’s mission has been to build a research cohort that can better reflect populations historically underrepresented in biomedical research. If the wearable component succeeds on those terms, it could help narrow one of digital medicine’s most persistent gaps: the mismatch between who generates the data and who is meant to benefit from the resulting insights.







