In 2025, Melody Ding and a team from The University of Sydney reviewed 35 studies with over 16,000 adults from 2014-2025. They analyzed how daily step counts affect eight health outcomes, including heart disease, type 2 diabetes, dementia, cancer, depression, falls, physical function, and overall death risk, using data from PubMed and EBSCO CINAHL.

A 2025 meta-analysis published in Physiological Measurement evaluated 56 studies assessing the Apple Watch’s accuracy in monitoring health metrics. The findings indicate that while the device reliably measures heart rate and step counts, its accuracy in estimating energy expenditure (calories burned) is limited.