https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6292246/
A study of 2,202 randomly selected residents of three European nations (Iceland, Sweden, and Belgium) gathered data on sleep characteristics and the use of psychoactive substances including coffee. 44 They found that caffeine consumption did not predict difficulties inducing sleep or other sleep disturbances when age, gender, smoking, and

https://www.nbcnews.com/health/health-news/brain-scans-coffee-drinkers-caffeine-rcna91680
However, the MRI scans showed that drinking coffee increased activity in parts of the brain involved in short-term memory, attention and focus, whereas ingesting caffeine on its own did not. The

https://jcsm.aasm.org/doi/10.5664/jcsm.3170
The sleep disruptive effects of caffeine administration at bedtime are well documented. 17 Indeed, caffeine administration has been used as a model of insomnia. 18 Dose-response studies demonstrate that increasing doses of caffeine administered at or near bedtime are associated with significant sleep disturbance. 19 -21 One of the most common recommendations for appropriate sleep hygiene

https://www.nature.com/articles/s41598-021-84088-x
Caffeine is an adenosine receptor antagonist, which blocks the A 1 and A 2A adenosine receptors in the central nervous system 1. It may, thus, attenuate the increase in sleep pressure during

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3805807/
The results of this study suggest that 400 mg of caffeine taken 0, 3, or even 6 hours prior to bedtime significantly disrupts sleep. Even at 6 hours, caffeine reduced sleep by more than 1 hour. This degree of sleep loss, if experienced over multiple nights, may have detrimental effects on daytime function. 40 - 42 Thus, the present results

https://www.news-medical.net/news/20210204/New-report-reviews-effect-of-coffee-on-sleep-and-wake-cycles.aspx
It reviews the latest research into coffee's effect on sleep and suggests that while drinking coffee early in the day can help support alertness and concentration levels, especially when sleep

https://www.nature.com/articles/s41380-021-01075-4
Coffee is the most widely consumed beverage, with particular interest for human health in view of its short-term effects on attention, sleep, and memory and its long-term impact on the appearance

https://www.houstonmethodist.org/blog/articles/2021/oct/caffeine-sleep-how-long-does-caffeine-keep-you-awake/
Its levels in your brain fluctuate — fairly low when you wake up and slowly building throughout the day. After several hours of being awake, adenosine levels increase to a point where they start the process of making you sleepy. Unless its receptors are blocked by caffeine, that is. When this happens, the downstream sleep-promoting pathways

https://www.washingtonpost.com/wellness/2023/03/22/coffee-heart-palpitations-sleep-exercise/
Coffee lovers gain 1,000 steps a day, but get less sleep, study shows. A rigorous new study looked at the various effects coffee has on health, including exercise, sleep and heart palpitations. A

https://www.science.org/doi/10.1126/science.aad2958
A new study by Burke et al. ( 1) reveals that consuming caffeine in the evening—the equivalent of a double espresso—delays the human endogenous circadian clock by antagonizing receptors for the endogenous sleep factor adenosine in the brain (see the figure). Mistimed caffeine consumption may contribute to the growing incidence of sleep

https://msutoday.msu.edu/news/2021/caffeine-and-sleep
Consistently lacking adequate sleep not only affects cognition and alters mood, but can eventually take a toll on immunity. "Caffeine increases energy, reduces sleepiness and can even improve mood, but it absolutely does not replace a full night of sleep, Fenn said. "Although people may feel as if they can combat sleep deprivation with

https://www.livescience.com/how-does-caffeine-affect-sleep
A 2013 study in the Journal of Clinical Sleep Medicine divided people into three groups, with individuals drinking caffeine 6 hours, 3 hours or immediately before bedtime. Even those who stopped

https://www.sleepfoundation.org/nutrition/caffeine-and-sleep
Caffeine affects the brain by blocking adenosine receptors . Adenosine is a sleep-promoting chemical that is produced in the brain during our waking hours. Normally, adenosine builds up in the brain the longer you are awake. The more it builds up, the sleepier you become. When caffeine blocks this process, you remain alert and vigilant.

https://neurosciencenews.com/coffee-circadian-rhythm-17677/
This was reported in a study which found that consuming 300mg of caffeine (or three cups of coffee) per day can help to improve people's vigilance, alertness, reaction-time, accuracy and working memory in the first three days of poor sleep, compared to decaffeinated coffee. For those working nightshifts, consuming caffeine has been found to

https://nypost.com/2022/01/26/neuroscientist-explains-why-you-should-have-a-coffee-before-you-sleep/
Brice says that drinking coffee immediately before a 20 to 30-minute nap will help you to overcome grogginess when you wake up, The Times reported. "Caffeine takes about 20 minutes to kick in

https://www.verywellhealth.com/why-does-coffee-make-me-sleepy-8584745
Caffeinated Drinks. How to Feel Awake. People drink coffee for its ability to increase alertness. However, for some people, coffee makes them more tired. This is likely due to caffeine blocking the receptors of a chemical found in human cells called adenosine. It may also be due to poor sleep habits or the development of caffeine tolerance.

https://edition.cnn.com/2023/03/27/health/coffee-fitness-sleep-heart-effects-wellness/index.html
On coffee-drinking days, participants got an average of 1,058 more steps than they did on abstention days, the authors found. But on those days, sleep took a hit, with participants getting 36

https://www.medicalnewstoday.com/articles/drinking-coffee-may-help-lower-death-risk-being-sedentary
Researchers also reported that non-coffee-drinking participants who sat for six hours or more a day were about 1.6 times more likely to die from all causes than coffee drinkers who sat for less

https://www.upi.com/Health_News/2021/06/03/coffee-sleep-deprivation-doesnt-work-study/1791622692544/
An 8-ounce cup of regular coffee may contain 75 to 120 mg of caffeine. Sleep loss impaired performance on both tasks. Caffeine helped people successfully achieve the easier task, but not the more

https://www.youtube.com/watch?v=8nYm23alKmQ
Looking to understand the health benefits and risks of coffee consumption? Check out this recent study published in The New England Journal of Medicine. The

https://www.cnn.com/2022/09/29/health/coffee-live-longer-wellness/index.html
CNN —. Drinking two to three cups a day of most types of coffee may protect you from cardiovascular disease and an early death, a new study found. "The results suggest that mild to moderate

https://www.health.harvard.edu/heart-health/does-coffee-help-or-harm-your-heart
In the 1960s, coffee was considered a risk factor for coronary artery disease, although later research suggested that only heavy coffee consumption (more than five or six cups a day) might harm the heart. But people who drink excessive amounts of coffee often differ in many other ways from those who enjoy modest amounts, Dr. Gaziano notes.

https://www.thesleepscientist.com/post/does-caffeine-really-affect-your-sleep-quality
In this way, caffeine temporarily blocks the effects of sleep pressure. Caffeine can also promote the 'fight or flight' stress system, increasing adrenaline and cortisol, and making it harder to relax. It typically takes 30-45 minutes for the alerting effects of caffeine in a drink to peak, and the effects typically last 3 to 5 hours.

https://www.washingtonpost.com/wellness/2024/06/17/coffee-health-benefits-comparison/
In the article, researchers reported that non-coffee drinkers who sat six hours or more per day were 58 percent more likely to die of all causes than coffee drinkers sitting for less than six

https://www.health.harvard.edu/staying-healthy/drinking-coffee-linked-to-healthier-hearts-and-longer-lives
In a recent observational study published online Sept. 27, 2022, by the European Journal of Preventive Cardiology, researchers found that people who drank two to three cups of coffee each day had a lower risk of cardiovascular disease and early death than those who avoided the beverage. The study included almost 450,000 people (average age 58

https://www.sciencedaily.com/releases/2024/06/240618153024.htm
The effects of coffee consumption on human health is a knotty question, but one thing is sure: coffee is a psychoactive substance. Coffee drinking is a heritable habit, and one that carries a

https://www.msn.com/en-us/health/medical/drinking-your-cup-of-coffee-every-morning-could-stop-you-from-dying-young/ar-BB1oXvkx
New research from scientists working at Soochow University in Suzhou, China suggests drinking coffee can help negate some of the bad effects of living a very sedentary lifestyle, and in theory

https://fortune.com/well/article/best-time-to-drink-coffee/
Globally, coffee consumption has risen, and two-thirds of Americans drink coffee daily, according to 2022 data from the National Coffee Association.And even amid coffee supply-chain issues, people