Human study · Research · 22 Sept 2026
Coffee doesn’t have to keep you awake to disrupt your sleep
Source: ScienceDaily
What the research found
Caffeine may make sleep less restorative even when you fall asleep normally and stay in bed for eight hours, with EEG recordings revealing fewer of the slow brain waves associated with deep sleep. Individual sensitivity varies dramatically, meaning even caffeine consumed earlier in the day could affect nighttime recovery for some people.
Evidence level: Human study. A study in people, but an association isn't proof of cause.
More research news
- In mice, fear made hippocampal maps of a safe place and a dangerous place overlap
- In pregnant mice, immune activation at day 12.5 lined up with placental injury and autism-like traits in male fetuses only
- Support cells in brain tissue from 73 people with Parkinson's showed sex differences in energy-gene and myelin-gene activity
- In 10,362 adults, night-to-night swings in sleep timing lined up with a higher risk of serious cardiovascular events
- In a U.S. telephone survey of 442,906 adults, reported cannabis use lined up with higher odds of cardiovascular disease, especially stroke