Drinking coffee before bed actually has little effect on sleep, study finds
Those who smoked or vaped before bed saw their sleep suffer the most
Having a coffee before bed will cause less disruption to your sleep pattern than a nightcap, new research has found.
Despite the age-old advice that caffeine close to bedtime will keep you up, researchers have found the effects of alcohol and cigarettes to be more unsettling.
Researchers from Florida Atlantic University, Harvard, Emory, and the Mississippi Medical Centre studied the sleeping patterns of 785 African American participants over the course of 14 years using a wrist monitor.
They found that drinking caffeine within four hours of going to bed had little impact on sleep, but consuming alcohol was far more likely to bring on insomnia. However it was those who smoked or vaped before bed that suffered the most, getting on average 43 less minutes sleep than their non-smoking counterparts.
While none of the participants in the study suffered with any pre-existing sleeps disorders, researchers chose to study African Americans as they suffer a disproportionate percentage of sleep disorders, such as insomnia and sleep apnea, compared with others.
Even after controlling other factors that could affect sleep such as gender, weight, age, stress or other mental health conditions, the study concluded that caffeine had little impact on sleep.
As well as providing the data from their wrist monitor, each participant was asked to keep a journal to record any caffeine, alcohol and cigarettes consumed within four hours of going to sleep.
The study is the largest longitudinal research to consider the impact of all three variables on quality of sleep.
Researchers did note however that the study did not measured individual tolerance levels, which “can play an important role in the association between caffeine use and sleep.”
Updated: August 8, 2019 10:40 AM