Researchers from Florida Atlantic University, Harvard, Emory, and Mississippi Medical Center coalesced and did a study which found that coffee or caffeine has little to do with sleep.
The study was done in the span of 14 years which consisted of 785 African Americans as respondents that have no clinical sleep disorders. The reason for choosing African Americans is that these group of people, as proven by studies, suffer more from insomnia, sleep apnea, and other sleep disorders compared to other groups.
The study is one of the longest and most important on the subject of how alcohol, caffeine, and smoking at night affects sleep.
Every participant was given a wristwatch that had the ability to monitor sleep.
The participants were also asked to write down how they slept, how they felt, and what they ate, smoked or drank nightly in a journal.
There is a huge chance that the respondents could have just made up their answers, but the researchers claim that the answers they received were mostly honest.
Whether a respondent was obese, male or female, having to go to work or school, feeling anxious, stressed or depressed, caffeine did not affect sleep at all, the study finds.
Respondents who reported to have had a hard time sleeping at night were drinking alcohol, especially closer to their bed time.
Nicotine, on the other hand, had a worse effect. Smokers have 43 minutes less sleep time than those who don’t do it.