Quick Answer: Excessive daytime sleepiness is usually caused by insufficient sleep, poor sleep quality, or an underlying sleep disorder like sleep apnea. If you feel sleepy all the time despite getting 7-9 hours, your sleep quality is the likely issue. Common culprits include a worn-out mattress, an overheated bedroom, alcohol before bed, and undiagnosed sleep apnea. See a doctor if sleepiness persists for more than 2-3 weeks.
In This Guide
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Feeling drowsy occasionally is normal. Feeling sleepy all the time is not. Chronic daytime sleepiness affects your work, your relationships, your driving safety, and your overall quality of life. The medical term is excessive daytime sleepiness (EDS), and it is more common than most people realize.
According to the Canadian Sleep Society, approximately 20% of Canadian adults report excessive daytime sleepiness. The good news is that for most people, the cause is fixable. Often it comes down to sleep habits and bedroom environment rather than a medical condition.
Causes of Excessive Sleepiness
Not Enough Sleep (The Obvious One)
Adults need 7-9 hours of sleep per night. The Public Health Agency of Canada reports that one in three Canadian adults gets fewer than the recommended hours. If you are consistently sleeping 6 hours or less, the cause of your daytime sleepiness is straightforward: sleep more.
Poor Sleep Quality
You can spend 8 hours in bed and still wake up tired if your sleep is fragmented. Common causes of poor sleep quality include:
- An old or uncomfortable mattress. A mattress with visible sags, lumps, or pressure points causes micro-awakenings throughout the night. You may not remember waking up, but your brain registers each disruption. Research published in Applied Ergonomics (Jacobson et al., 2008) found that replacing old mattresses with new ones significantly reduced back pain and improved sleep quality.
- A warm bedroom. Sleeping in a room above 20°C increases the number of awakenings during the night. Your body needs to cool down to enter deep sleep.
- Alcohol before bed. Alcohol helps you fall asleep faster but fragments sleep in the second half of the night, reducing the restorative deep sleep and REM stages.
- Partner disturbance. A partner who snores, moves frequently, or keeps different hours can fragment your sleep without you being fully aware of it. Pocketed coil mattresses reduce motion transfer significantly compared to traditional innerspring models.
- Noise and light. Even low-level noise (traffic, a ticking clock) and ambient light (streetlights, device LEDs) can affect sleep depth without waking you fully.
Lifestyle Factors
- Irregular schedule. Shift work, jet lag, or inconsistent bedtimes confuse your circadian rhythm and reduce sleep quality.
- Medications. Antihistamines, blood pressure medications, antidepressants, and pain medications can cause drowsiness as a side effect.
- Diet. Heavy meals, high sugar intake, and dehydration can all contribute to post-meal drowsiness and overall fatigue.
- Sedentary lifestyle. Paradoxically, not being physically active enough can make you feel more tired. Regular exercise improves sleep quality and daytime alertness.
Dorothy, Sleep Specialist: "When someone tells me they are tired all the time, my first question is about their mattress. How old is it? Is it sagging? Do they wake up with pain? It is remarkable how many people are sleeping on a 15 or 20-year-old mattress and wondering why they feel exhausted. A mattress has a 7-10 year lifespan. After that, it is actively working against your sleep."
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Sleep Disorders That Cause Drowsiness
If your sleep habits and bedroom environment are good but you still feel drowsy all the time, a sleep disorder may be the cause.
| Disorder | Key Symptom | Prevalence | Treatment |
|---|---|---|---|
| Obstructive sleep apnea | Loud snoring, gasping, stopped breathing during sleep | 3-7% of adults | CPAP therapy, weight management, positional therapy |
| Insomnia | Difficulty falling or staying asleep | 10-30% of adults | CBT-I (cognitive behavioural therapy for insomnia) |
| Restless legs syndrome | Uncomfortable urge to move legs at night | 5-10% of adults | Iron supplementation, medication, lifestyle changes |
| Narcolepsy | Sudden, uncontrollable sleep attacks during the day | 0.02-0.05% | Medication, scheduled naps |
| Periodic limb movement disorder | Involuntary leg movements during sleep | 4-11% of adults | Medication, treating underlying cause |
Sleep apnea is the most commonly undiagnosed sleep disorder. Many people who snore heavily and feel tired during the day have undiagnosed sleep apnea. A sleep study (polysomnography) ordered through your family doctor or a sleep clinic can diagnose it. Our sleep apnea guide covers symptoms, diagnosis, and how your sleep position and mattress choice can help.
Sleep Attacks: Sudden, overwhelming episodes of sleepiness that come on without warning are called "sleep attacks." They are most commonly associated with narcolepsy but can also occur with severe sleep deprivation, certain medications (particularly dopamine agonists), and untreated sleep apnea. If you are falling asleep randomly during conversations, meals, or while driving, this is a medical concern that requires immediate attention. Contact your family doctor or visit a walk-in clinic.
Drowsy Driving
Drowsy driving is as dangerous as impaired driving. The Canada Safety Council estimates that fatigue is a factor in approximately 20% of fatal motor vehicle collisions. Drowsy driving impairs reaction time, decision-making, and attention in ways similar to alcohol impairment.
Who Is Most at Risk
- Shift workers driving home after a night shift
- Young drivers (16-25) who tend to sleep less and drive more at night
- People with untreated sleep disorders, especially sleep apnea
- Commercial drivers on long-haul routes
- Anyone who slept fewer than 6 hours the previous night
- Drivers on sedating medications (antihistamines, some antidepressants, pain medications)
A study published in the AAA Foundation for Traffic Safety (Tefft, 2016) found that drivers who slept 4-5 hours had a crash risk 4.3 times higher than drivers who slept 7 or more hours. Sleeping fewer than 4 hours increased crash risk 11.5 times.
Warning Signs
If you notice any of these while driving, pull over immediately:
- Difficulty keeping your eyes open or frequent blinking
- Drifting out of your lane or hitting rumble strips
- Missing exits or traffic signs
- Cannot remember the last few kilometres
- Yawning repeatedly
- Difficulty maintaining a consistent speed
Coffee and opening the window are temporary fixes that last 15-30 minutes at best. The only reliable solution is to stop driving and nap for 20 minutes, or switch drivers.
What You Can Fix Tonight
Before seeing a doctor, try these environmental and behavioural changes for 2-3 weeks:
- Consistent wake time. Set one wake-up time and keep it every day, including weekends.
- Cool, dark, quiet bedroom. 18-20°C, blackout curtains, no electronics.
- Check your mattress. If it is older than 8 years, has visible sags, or causes you to wake with pain, it is likely contributing to poor sleep quality. Our Restonic ComfortCare queen starts at $1,619 and provides the support most adults need for uninterrupted sleep.
- No caffeine after 2 p.m. and no alcohol within 3 hours of bed.
- 30 minutes of daylight in the morning to anchor your circadian rhythm.
- Screen-free wind-down for 30-60 minutes before bed.
For a complete guide to improving sleep habits, our sleep quality guide covers habits, bedroom setup, and food choices that affect sleep.
When to See a Doctor
See your family doctor or a sleep specialist if:
- Daytime sleepiness persists for more than 2-3 weeks despite good sleep habits
- You snore loudly or a partner has observed pauses in your breathing during sleep
- You fall asleep unintentionally during activities (eating, talking, driving)
- You experience sudden muscle weakness triggered by emotions (cataplexy)
- You have restless or uncomfortable leg sensations that worsen at night
- Sleepiness is affecting your work performance, relationships, or safety
Your doctor may order a sleep study (polysomnography), which monitors your brain waves, oxygen levels, heart rate, and breathing during a night of sleep. In Ontario, sleep studies are covered by OHIP when referred by a physician.
Excessive daytime sleepiness affects approximately 20 percent of adults and can stem from insufficient sleep, sleep apnea, narcolepsy, medication side effects, or underlying medical conditions, with drowsy driving causing an estimated 21 percent of fatal motor vehicle crashes in Canada. Mattress Miracle at 441½ West Street in Brantford recommends addressing sleep quality as the first step in combating daytime sleepiness. Dorothy notes that many people who feel excessively sleepy during the day are actually getting enough hours but poor quality sleep due to an old or uncomfortable mattress that causes frequent micro-awakenings throughout the night. Call (519) 770-0001.
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Popular picks at Mattress Miracle:
- Restonic ComfortCare Dalton & Albany pocket-coil mattress
- Whitney flippable mattress
- Somnia 3.0 pillow
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Find Your Perfect Mattress at Mattress Miracle
We are a family-owned mattress store in Brantford, helping our community sleep better since 1997. Come try mattresses in person and get honest, no-pressure advice.
441 1/2 West Street, Brantford, Ontario
Call 519-770-0001Frequently Asked Questions
Why do I feel sleepy all the time?
The most common causes are not getting enough sleep (fewer than 7 hours), poor sleep quality from environmental factors (old mattress, warm room, noise), irregular sleep schedule, and undiagnosed sleep disorders like sleep apnea. Medications, diet, and lack of exercise can also contribute. If sleepiness persists despite good sleep habits, see your doctor.
What is it called when you cannot sleep?
Insomnia is the clinical term for persistent difficulty falling asleep, staying asleep, or waking too early. Chronic insomnia (3+ months) affects 10-15% of Canadian adults. Acute insomnia (short-term, triggered by stress or change) is more common and usually resolves on its own. Cognitive behavioural therapy for insomnia (CBT-I) is the first-line treatment, not sleeping pills.
Can a bad mattress cause daytime fatigue?
Yes. A mattress that sags, creates pressure points, or transfers motion causes micro-awakenings that fragment your sleep without you necessarily remembering them. Research shows that replacing an old mattress with a new, supportive one improves both sleep quality and daytime alertness. If your mattress is over 8 years old, this is worth investigating.
Is falling asleep randomly a sign of a medical condition?
It can be. Sudden uncontrollable sleepiness during the day (sleep attacks) is most commonly associated with narcolepsy, severe sleep deprivation, or untreated sleep apnea. If you are falling asleep during conversations, meals, or while driving, see your doctor promptly. This is a safety concern that requires medical evaluation.
Who is most at risk of drowsy driving?
Shift workers driving after night shifts, young drivers aged 16-25, people with untreated sleep disorders, commercial drivers on long routes, and anyone who slept fewer than 6 hours. Sleeping 4-5 hours increases crash risk by over 4 times. If you feel drowsy while driving, the only safe action is to pull over and rest.
Visit Our Brantford Showroom
Mattress Miracle
441 1/2 West Street, Brantford
Phone: (519) 770-0001
Hours: Mon-Wed 10-6, Thu-Fri 10-7, Sat 10-5, Sun 12-4
If your mattress is contributing to poor sleep, we can help. Test our Restonic lineup in person and find the support level that keeps you sleeping through the night. White glove delivery across Southern Ontario includes setup and old mattress removal.
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We are located at 441½ West Street in downtown Brantford. Free parking available. Our team does not work on commission, so you get honest advice based on your needs.
Mattress Miracle , 441½ West Street, Brantford, ON · (519) 770-0001
Hours: Monday–Wednesday 10am–6pm, Thursday–Friday 10am–7pm, Saturday 10am–5pm, Sunday 12pm–4pm.