Factors that impair your sleep

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Just as there are factors that help your sleep, specific factors can also interfere with it.


The neurotransmitter​ adenosine works by fitting into specific cell receptors, similar to a lock and key. The chemical caffeine, found in coffee, cola and energy drinks, fits the same cell receptors as adenosine. This means that consuming caffeine can block the adenosine receptors and prevent adenosine from creating the feeling of sleepiness.

The American Academy of Pediatrics recommends that teens (aged 19 and younger) get no more than 100 mg of caffeine a day. Adults (aged 20 and older) with a medical condition should get no more than 200 mg of caffeine per day.

Check out this list to find out how much caffeine is in your favourite drinks and sweets. Could this be interfering with your sleep?

Take a look through the list to see if you can find the top three drinks you should try to avoid.


Type of coffee ​Milligrams of caffeine
Decaffeinated 2
Instant (8 fl oz.) 57
Espresso (1 oz.) ​77
Brewed (8 fl oz.)​108
Starbucks, short brewed (8 fl oz.) ​180
Starbucks, tall brewed (12 fl oz.)​260
Starbucks, grande brewed (16 fl oz.)​330
Starbucks, venti brewed (20 fl oz.)​415


Type of tea​ ​Milligrams of caffeine
Herbal 0
Decaf 5
Green ​25
Arizona Iced (20 fl oz.) ​38
Lipton Iced (20 fl oz.)​48
Lipton (8 fl oz.)​55


Type of chocolateMilligrams of caffeine
Dark chocolate (1 oz.)12
Milk chocolate (1 cup, chips)34

Selected soft drinks

Brand (12 oz. serving)​​Milligrams of caffeine
7-UP 0
Sprite 0
A&W Root Beer ​0
Barq's Root Beer​23
Cola-Cola (Classic) ​34
Pepsi Cola​38
Dr. Pepper​41
Coke Zero​45
Diet Coke​45
Mountain Dew​54

Energy drinks

Brand (12 oz. serving)​​Milligrams of caffeine
VitaminWater Energy Drink (11.5 fl oz.)80
​Red Bull (8.46 fl oz.)80
Rockstar (16 fl oz.)​160
Monster (16 fl oz.)​160
NOS Energy Drink (16 fl oz.)​160
Crave Energy Drink (16 fl oz.)​192
5 Hour Energy Shot (2 fl oz.)​​200
Pure Kick Energy Drink (20 fl oz.)​200
10 Hour Energy Shot (1.93 fl oz.)​422

For more specific information on caffeine consumption, check out Health Canada’s guidelines.

Poor sleep hygiene

“Sleep hygiene” describes the routine you create for your sleep every night. It is important to avoid poor sleep hygiene so your brain can learn to associate your bed only with sleep.

If you do activities that are keep you wide awake in bed, your brain will have a more difficult time settling down to rest when it’s sleep time. For this reason, it’s very important to avoid doing stressful activities right before bedtime or in bed. So instead of studying for a test in bed, for example, do your study in the living room. You can find out more about developing good sleep hygiene​ later in this session.

Electronic devices and television

It might not seem like a big deal to quickly check your phone, tablet or laptop before you drift off to sleep, but these devices can particularly disrupt your sleep routine. This is because these devices emit mostly blue light, which is very high intensity and associated with morning. This, coupled with the fact that handheld electronic devices are generally held very close to your eyes, means that the devices can confuse your brain into thinking that it’s time to start waking up instead of falling asleep.

The light from electronic screens (TVs, computers, phones, e-readers and so on) can interfere with sleep. Electronic devices also take away from sleep by reducing your overall sleep opportunity. In fact, studies have shown that people sleep less when electronic devices are present in the bedroom. Videogames are particularly demanding on your attention; avoid playing them in bed at all times.

Televisions are less disruptive to sleep than other electronic devices because the light they emit is usually yellow rather than blue. In addition, TVs are further from your eyes than a handheld device. However, if you fall asleep with the TV on, the noise and light from the TV will continue to act as a stimulus, making it difficult to have a restful sleep.​​

Last updated: May 2nd 2016