Sleep and substances

Sleep and caffeine

Caffeine, found in coffee, tea and cocoa, boosts energy by blocking adenosine, which causes sleepiness. However it can distrupt sleep as it lingers in your body for over six hours. The length of time caffeine lasts in your system, varies from person to person with some studies showing it can last little as four hours and as long as 16 hours!  Not only does caffeinated beverages impact your ability to sleep, but they also impact the quality of sleep you get. For your first caffeinated beverage of the day, our Alcohol and Drug clinician suggests that you wait two- three hours after you wake up before having that morning coffee. This allows your body's cortisol levels to even out and can help prevent afternoon fatigue.  And for your last caffeinated beverage of the day, avoid an afternoon cuppa, because consuming caffeine six hours before bedtime can reduce your total sleep time by an hour! Overall it is best to limit your caffeine intake to around 300-400 mg per day. This varies depending on which caffeinated beverage you have and we suggest looking at the caffeine contents of your beverages, as you may be surprised by how much caffine they have! For example, Green tea and cola drinks have around 30-35mg of caffeine in them. While instant coffee and black tea both have around 50mg and energy drinks have a whopping 80-120mg in a  small 250 ml can.  

Sleep and nicotine

Generally, people don’t realise how nicotine, tobacco, and vaping products with nicotine impacts sleep quality and quantity.  Nicotine is a stimulant, and releases neurotransmitters (i.e., serotonin) that is associated with pleasurable feelings. However, frequent smoking and vaping can create inconsistent levels of these neurotransmitters in your brain, resulting in trouble sleeping, as well as less time spent in  a deep and restorative sleep. This results in difficulty getting up in the mornings and additional daytime sleepiness and insomnia-like symptoms. Heavy smoking use can also be especially troublesome if you have respiratory conditions, such as asthma, as smoking can exacerbate respiratory problems and cause frequent sleep disturbances. If you’d like to know more about how certain drugs may impact your sleep, check out The Level.

If you experience issues with substances and sleep, please contact our Alcohol and Drug Clinician.

Sleep and alcohol

Although alcohol may help you doze off faster, it  often results in lighter sleep and overall reduced sleep quality. Even if you drink a low intake, alcohol reduces the quality of sleep from the get-go. Alcohol reduces sleep onset latency, which can cause significant sleep disruptions in the later half of your sleep. Moderate to high doses of alcohol (more than two standard drinks) impact your REM (Rapid Eye Movement) in your sleep, which is needed to feel well rested and awake the following day.  To manage alcohol’s sleep influence, limit your intake to no more than two standard drinks in a day.   

Sleep and cannabis

People assume that cannabis helps you fall asleep. This may be true for infrequent and short-term use, but it is not recommended as a long-tern use sleeping aid as it can reduce sleep quality. Frequent cannabis use leads to more difficulty with sleeping, whether that be waking up early and not being able to fall asleep again, difficulty falling asleep, or experiencing consistent sleep disturbances. Long-term cannabis use generally causes some people to develop a tolerance to its sedative effects.  Heavy, frequent, long-term cannabis use can create impaired memory and more daytime sleepiness.  If you are taking cannabis, in any shape or form, keep an eye out for synthetic cannabinoids. Synthetic cannabinoids can make you feel extra drowsy, dizzy, groggy, panicked, and even unable to maintain consciousness (also known as ‘dropping’) which can impact your sleep quality and quantity significantly. The Level has more information on how to safely use cannabinoids. 

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