Terra API announced that Terra Research has published a peer-reviewed sleep study in npj Biological Timing and Sleep, a Nature Portfolio journal.
The study examines how daylight duration relates to sleep duration across different geographies. The main finding was that longer daylight was associated with slightly shorter sleep, with sleep duration decreasing by about 4.4 minutes for each additional hour of daylight.
The research also found that daylight duration was more informative than broad seasonal labels such as winter or summer. Once daylight duration was included in the model, season itself added little explanatory value.
The Nature Portfolio publication is available here:
https://www.nature.com/articles/s44323-026-00092-2
Terra API’s official research summary is available here:
https://tryterra.co/research/terra-research-nature-publication