Sleep test experts interpret using 4 billion data points

Fitbit stated that clinical trials have proven that it is possible to accurately distinguish between light sleep, deep sleep, and REM sleep stages through band-type activity trackers equipped with movement and heart rate measurement functions, such as the Fitbit Alta HR, Blaze, and Charge 2.

Polysomnography experts analyzed over 4 billion data points collected through Fitbit and found that the band-type activity tracker measures an adult's sleep stages with significant accuracy, allowing users to save on future costs such as visiting a sleep laboratory (for treatment, etc.).

Dr. Henegan, who participated in the study, said, “With Fitbit’s technology making it possible to measure sleep stages—which were previously only possible in sleep laboratories—through wristband trackers, the way we check information about our sleep habits has completely changed.” He added, “If sleep quality can be measured so easily, individuals can gain an accurate understanding of their own sleep, while society can raise awareness of public health and gain new insights into previously unknown information about sleep and various health conditions.”

In April of this year, Fitbit introduced a new sleep feature to allow users to check their sleep habits more accurately. The sleep stage feature currently available on Alta HR, Blaze, and Charge 2 measures light sleep, deep sleep, and REM sleep duration using heart rate changes, as well as measuring the time spent awake each night, allowing for detailed monitoring of sleep quality.

In addition, Fitbit recently conducted an investigation and analysis of millions of anonymized Fitbit night sleep stage data points, proving the theory that sleep scientists have long argued that more than 7 hours of sleep is best for health. Leading sleep researchers have claimed that there is a correlation between less than 7 hours of sleep and a lack of REM sleep, and that a lack of REM sleep can affect short-term memory, cell regeneration, and the regulation of psychological state.


Dr. Michael T. Smith, Jr., a sleep expert on the Fitbit advisory board and professor of neuropsychiatric nursing at Johns Hopkins School of Medicine, said, “The results of this study support the general recommendation that most adults should consistently sleep 7 to 9 hours and demonstrate why getting good sleep is important for overall well-being. When sleeping less than 7 hours, the body may lack both deep sleep and REM sleep, and these two sleep stages are crucial for maintaining overall health.”