M. Jackson Group Update – February 2023 – The Effect of Caffeine on Sleep

A collection of postings on a range of issues is available on our website (www.mjacksongroup.ca).  This month’s post is again from Ken Pope’s listserv, where he kindly provides daily summaries of current articles in the field.

The article is as follows:Sleep Medicine Reviews has scheduled a study for publication in a future issue: “The effect of caffeine on subsequent sleep: A systematic review and meta-analysis.”
The authors are Carissa Gardiner a b, Jonathon Weakley a b c, Louise M. Burke d, Gregory D. Roach e, Charli Sargent e, Nirav Maniar b f, Andrew Townshend a b, & Shona L. Halson a b.

Here’s how it opens:
Sleep is an essential component of physical and emotional wellbeing [1]. Current recommendations outline the need for healthy adults to achieve seven to 9 h of sleep per night [2]. Despite the innate requirement to attain healthy sleep, insufficient sleep is a growing public health challenge. It is estimated that 20–45% of the population around the world are sleep deprived [[3][4][5][6]]. Short and fragmented sleep bouts may result in impaired cognitive functioning, diminished mood, and increased risk of accident or injury [1]. When sustained chronically, insufficient sleep contributes to the risk of health epidemics with a heightened probability of cardiometabolic disease and mental health disorders [7,8]. Negative outcomes of this nature carry a significant cost to the individual and society, through compromised health and reduced productivity [9]. As such, recommendations for positive sleep behaviours have been developed to provide individuals with strategies to optimise their sleep quantity and quality [10].

A common behavioural recommendation to optimise sleep is to avoid caffeine in close proximity to bedtime [10]. Caffeine is a widely accessible psychostimulant found in foods, supplements, and medications [11]. With its status as a socially acceptable drug, caffeine is consumed by approximately 80% of the world’s population [12]. Caffeine is an adenosine antagonist suggested to acutely reduce sleep pressure through action on the homeostatic component of sleep-wake regulation [13]. This action stimulates the central nervous system with a resulting decrease in the perception of fatigue and sleepiness [14]. For this reason, caffeine is commonly consumed throughout the day in response to insufficient sleep to promote a state of wakefulness [15]. However, the use of caffeine to stimulate wakefulness may result in impaired onset and maintenance of subsequent sleep [16], potentially creating a cycle of diminished sleep and subsequent caffeine reliance [17].

The half-life of caffeine displays large variation across healthy adults (two to 10 h) [18], making it difficult to identify the appropriate time of day to discontinue caffeine intake to minimise disruptions to sleep. Currently, recommendations for positive sleep behaviours display a lack of precision in terminology. For example, the American Academy of Sleep Medicine warns that caffeine may cause sleep disruption if taken “too close to bedtime” [19], while the Sleep Health Foundation suggests consumers should “avoid caffeine close to bedtime” [20]. The lack of precision in these recommendations may limit the ability of consumers to make evidence-based decisions regarding the timing of their caffeine intake. A previous systematic review by Clark and Landolt [21] confirmed the negative association between caffeine and subsequent sleep. However, this review did not include a quantitative synthesis of the findings. In particular, the impact of the dose and timing of caffeine intake on subsequent sleep has yet to be quantified systematically. The aims of this systematic review and meta-analysis are to: 1) establish the level of evidence for the effect of caffeine intake on the characteristics of subsequent sleep (i.e., total sleep time, sleep onset latency, rapid eye movement (REM) onset latency, wake after sleep onset, sleep efficiency, sleep architecture, and subjective sleep quality; 2) quantify the effect of caffeine intake on the characteristics of subsequent sleep; and 3) quantify the influence of the dose and timing of caffeine intake on the characteristics of subsequent sleep. The review will provide evidence-based guidance to support recommendations regarding caffeine consumption to minimise decrements in subsequent sleep.

Here’s the abstract:
The consumption of caffeine in response to insufficient sleep may impair the onset and maintenance of subsequent sleep. This systematic review and meta-analysis investigated the effect of caffeine on the characteristics of night-time sleep, with the intent to identify the time after which caffeine should not be consumed prior to bedtime. A systematic search of the literature was undertaken with 24 studies included in the analysis. Caffeine consumption reduced total sleep time by 45 min and sleep efficiency by 7%, with an increase in sleep onset latency of 9 min and wake after sleep onset of 12 min. Duration (+6.1 min) and proportion (+1.7%) of light sleep (N1) increased with caffeine intake and the duration (−11.4 min) and proportion (−1.4%) of deep sleep (N3 and N4) decreased with caffeine intake. To avoid reductions in total sleep time, coffee (107 mg per 250 mL) should be consumed at least 8.8 h prior to bedtime and a standard serve of pre-workout supplement (217.5 mg) should be consumed at least 13.2 h prior to bedtime. The results of the present study provide evidence-based guidance for the appropriate consumption of caffeine to mitigate the deleterious effects on sleep.

Here are the practice points:
1. Consuming caffeine prior to sleep reduces total sleep time and sleep efficiency, and increases sleep onset latency and wake after sleep onset.
2. Caffeine consumption alters subsequent sleep architecture with an increase in the occurrence of light sleep (N1) and a reduction in the occurrence of deep sleep (N3 and N4).
3. Reductions in total sleep time are dependent on the final dose of caffeine and the time of day that it is consumed relative to bedtime, with greater reductions occurring when larger doses are consumed closer to bedtime.
4. To avoid reductions in total sleep time, coffee (107.5 mg per 250 mL) should be consumed at least 8.8 h prior to bedtime and a standard serve of pre-workout supplement (217 mg) should be consumed at least 13.2 h prior to bedtime.


Jonathon Weakley, School of Behavioural and Health Sciences, Australian Catholic University, Brisbane, Australia — Jonathon.Weakley@acu.edu.au 

Ken Pope

Ken Pope, Nayeli Y. Chavez-Dueñas, Hector Y. Adames, Janet L. Sonne, and Beverly A. Greene

Speaking the Unspoken: Breaking the Silence, Myths, and Taboos That Hurt Therapists and Patients (APA, 2023) 

Hector Y. Adames, Nayeli Y. Chavez-Dueñas, Melba J.T. Vasquez, & Ken Pope:

Succeeding as a Therapist: How to Create a Thriving Practice in a Changing World (APA, 2022)

Ken Pope, Melba J.T. Vasquez, Nayeli Y. Chavez-Dueñas, & Hector Y. Adames:

Ethics in Psychotherapy & Counseling: A Practical Guide, 6th Edition (Wiley, 2021)

On a dark desert highway
Cool wind in my hair
Warm smell of colitas
Rising up through the air
Up ahead in the distance
I saw a shimmering light
My head grew heavy and my sight grew dim
I had to stop for the night

There she stood in the doorway
I heard the mission bell
And I was thinking to myself
“This could be Heaven or this could be Hell”
Then she lit up a candle
And she showed me the way
There were voices down the corridor
I thought I heard them say

Welcome to the Hotel California
Such a lovely place (such a lovely place)
Such a lovely face
Plenty of room at the Hotel California
Any time of year (any time of year)
You can find it here

Her mind is Tiffany-twisted
She got the Mercedes Benz
She got a lot of pretty, pretty boys
That she calls friends
How they dance in the courtyard
Sweet summer sweat
Some dance to remember
Some dance to forget

So I called up the Captain
“Please bring me my wine”
He said, ‘We haven’t had that spirit here
Since 1969″
And still those voices are calling from far away
Wake you up in the middle of the night
Just to hear them say

Welcome to the Hotel California
Such a lovely place (such a lovely place)
Such a lovely face
They livin’ it up at the Hotel California
What a nice surprise (what a nice surprise)
Bring your alibis

Mirrors on the ceiling
The pink champagne on ice
And she said, ‘We are all just prisoners here
Of our own device”
And in the master’s chambers
They gathered for the feast
They stab it with their steely knives
But they just can’t kill the beast

Last thing I remember, I was
Running for the door
I had to find the passage back
To the place I was before
“Relax, ” said the night man
“We are programmed to receive
You can check out any time you like
But you can never leave”

—Don Henley, Don Felder, & Glenn Frey



John Pullyblank, Ph.D., R.Psych. (#946)

Registered Psychologist

The M. Jackson Group Inc.

Rehabilitation Psychology, Assessment & Interventionwww.mjacksongroup.caNew Westminster:  (604) 540-2720Victoria: (250) 360-1680