Quick Answer: Adults need 7-9 hours of sleep, teenagers need 8-10 hours, and school-age children need 9-12 hours. The minimum amount of sleep needed for basic brain function is approximately 4-5 hours, but chronic short sleep causes cumulative cognitive decline. Seven hours is not enough for most teenagers. These recommendations come from the American Academy of Sleep Medicine and are endorsed by the Canadian Sleep Society.
In This Guide
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How much sleep you need is not a matter of opinion. The science is clear, and the recommendations are consistent across every major health organization in North America. What varies is how well people actually follow these guidelines. Spoiler: most Canadians do not get enough.
Sleep Chart by Age
The following recommendations come from the American Academy of Sleep Medicine (Paruthi et al., 2016) and are endorsed by the Canadian Paediatric Society and the Canadian Sleep Society.
| Age Group | Recommended Hours | Notes |
|---|---|---|
| Newborns (0-3 months) | 14-17 hours | Includes naps. Sleep patterns are irregular. |
| Infants (4-12 months) | 12-16 hours | Includes naps. Nighttime sleep consolidates. |
| Toddlers (1-2 years) | 11-14 hours | Includes 1-2 naps. Single nap by age 2. |
| Preschool (3-5 years) | 10-13 hours | Many stop napping by age 5. |
| School age (6-12 years) | 9-12 hours | Consistent bedtime is critical. |
| Teenagers (13-17 years) | 8-10 hours | Biology shifts sleep later. Most get under 7. |
| Young adults (18-25) | 7-9 hours | University schedules often conflict. |
| Adults (26-64) | 7-9 hours | Individual variation exists within this range. |
| Older adults (65+) | 7-8 hours | Sleep becomes lighter and more fragmented. |
These are total sleep hours, including naps for younger children. The ranges account for individual variation. Some adults genuinely function well on 7 hours; others need 9. Very few people truly need fewer than 7, despite what they might claim.
Sleep Guidelines for Adults
The 7-9 Hour Recommendation
The Public Health Agency of Canada and the Canadian 24-Hour Movement Guidelines recommend that adults aged 18-64 get 7-9 hours of good quality sleep per night, with consistent sleep and wake times. This is not a suggestion. It is a health guideline on par with exercise and nutrition recommendations.
Research published in Sleep (Watson et al., 2015) found that sleeping fewer than 7 hours is associated with increased risk of obesity, diabetes, hypertension, heart disease, stroke, depression, impaired immune function, and increased mortality. Sleeping more than 9 hours is also associated with some negative health outcomes, though the evidence is less clear on whether oversleeping is a cause or a symptom of underlying conditions.
Optimal Sleep Amount
For most adults, the optimal amount is whatever keeps you alert and functional throughout the day without caffeine after noon. If you need an alarm clock to wake up and you feel tired by 2 p.m. without coffee, you probably need more sleep than you are getting.
A practical test: during a vacation or long weekend with no obligations, go to bed at a consistent time and wake up naturally without an alarm. After 2-3 days of "catching up," the amount of sleep your body settles into is likely your optimal amount.
Brad, Owner, 40+ years of experience: "I used to be one of those people who bragged about sleeping 5 hours a night. Then I replaced my old mattress about 10 years ago and started sleeping 7 hours consistently. The difference in how I feel during the day is night and day. Pardon the pun. A good mattress makes those 7 hours actually count."
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Teenagers and Sleep
Teenagers are the most sleep-deprived age group in Canada, and it is not entirely their fault. Biology works against them.
Why Teenagers Stay Up Late
During puberty, the circadian rhythm shifts later by approximately 1-2 hours, a phenomenon called sleep phase delay. Melatonin release starts later in the evening and cortisol rises later in the morning. This means a teenager's body naturally wants to fall asleep around 11 p.m. to midnight and wake around 8-9 a.m.
Most Canadian high schools start between 8:00 and 8:30 a.m., which means teenagers need to wake by 7 a.m. or earlier. Combined with homework, extracurriculars, part-time jobs, and screen time, most teenagers get 6-7 hours instead of the recommended 8-10.
Teen Sleep and Academic Performance: A meta-analysis published in Sleep Medicine Reviews (Dewald et al., 2010) found that sleep quality, sleep duration, and daytime sleepiness are all significantly related to academic performance in adolescents. The relationship between sleep quality and grades was stronger than the relationship between sleep quantity and grades, meaning how well a teenager sleeps matters even more than how long.
Why Sleep Is Important for Teenagers
- Brain development. The prefrontal cortex (responsible for decision-making, impulse control, and planning) is still developing until the mid-20s. Sleep, particularly REM sleep, is essential for this development.
- Emotional regulation. Sleep-deprived teenagers show increased irritability, anxiety, and depressive symptoms. The Canadian Mental Health Association identifies sleep as a key factor in adolescent mental health.
- Physical growth. Growth hormone is primarily released during deep sleep (stage 3). Insufficient sleep during puberty can affect physical development.
- Athletic performance. A study in Pediatrics (Milewski et al., 2014) found that adolescent athletes who slept fewer than 8 hours were 1.7 times more likely to have a sports injury compared to those who slept 8 or more hours.
- Driving safety. Teen drivers who sleep fewer than 8 hours are at significantly higher risk of drowsy driving accidents.
Tips for Parents
- Set a family-wide screen curfew (no phones or tablets 30 minutes before bed)
- Keep bedrooms cool, dark, and free of electronics
- Do not use early morning wake-up as punishment for staying up late; it worsens the cycle
- A quality mattress matters for teenagers too. Growing bodies need proper support. Our Restonic ComfortCare twin starts at $625 with 690 pocketed coils.
- Weekend sleep catch-up should not exceed 1-2 hours more than weekday wake times
Minimum Sleep for Brain Function
The minimum amount of sleep needed for basic brain function is approximately 4-5 hours for a single night. Below this threshold, cognitive impairment becomes severe, similar to legal intoxication levels. A study published in Sleep (Van Dongen et al., 2003) found that restricting sleep to 4 hours per night for 14 days produced cognitive impairment equivalent to going without sleep for 48 hours.
However, there is no safe minimum for chronic sleep restriction. Sleep debt accumulates over time. Getting 5 hours per night for a week creates a cumulative deficit that affects attention, memory, reaction time, and decision-making, even if you feel like you have "adapted" to less sleep.
The "I Only Need 5 Hours" Myth
Approximately 1-3% of the population carries a genetic variant (DEC2 gene mutation) that allows them to function well on 6 hours or fewer. For the other 97-99% of people, claims of needing only 5 hours are almost always a case of being accustomed to impairment. Your baseline for "normal" shifts when you are chronically sleep-deprived, meaning you stop noticing how impaired you are.
Dorothy, Sleep Specialist: "I hear 'I only need 5 hours' from customers at least twice a month. Then they try a new mattress, start sleeping 7 hours, and come back saying they cannot believe how much better they feel. They had no idea what they were missing because they had been running on empty for so long."
Sleep needs vary by age, from 14 to 17 hours for newborns down to 7 to 9 hours for adults aged 18 to 64, with teenagers needing 8 to 10 hours despite social pressures that often cut their sleep short. Mattress Miracle at 441½ West Street in Brantford carries mattresses for every age group, from crib mattresses to adult models in all sizes. Brad notes that children and teenagers especially benefit from a mattress matched to their growth stage, as a supportive sleep surface during development years contributes to both physical growth and cognitive performance. Call (519) 770-0001.
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Call 519-770-0001Frequently Asked Questions
Is 7 hours of sleep enough for a teenager?
No. The American Academy of Sleep Medicine recommends 8-10 hours for teenagers aged 13-17. Seven hours is below the minimum recommendation and is associated with poorer academic performance, increased injury risk, and higher rates of anxiety and depression in adolescents. If your teenager consistently gets only 7 hours, work on adjusting their schedule to add at least one more hour.
What is the recommended amount of sleep for adults?
Seven to nine hours per night for adults aged 18-64, and seven to eight hours for adults aged 65 and older. These guidelines come from the American Academy of Sleep Medicine and the Canadian Sleep Society. Individual variation exists, but very few adults genuinely need fewer than 7 hours.
How much sleep does my brain need to function?
For a single night, approximately 4-5 hours prevents the most severe cognitive impairment. But there is no safe minimum for ongoing sleep restriction. Chronic sleep below 7 hours causes cumulative deficits in attention, memory, and decision-making that worsen over time, even if you feel adapted.
Is 2 hours of sleep enough?
No. Two hours of sleep provides minimal restorative value. After 2 hours, you will likely have completed one sleep cycle (typically 90-110 minutes), which includes some deep sleep. You will be functional but significantly impaired, roughly equivalent to a blood alcohol level of 0.05-0.10%. This is not sustainable and is dangerous for driving or operating equipment.
Why do older adults need less sleep?
The recommendation for older adults (65+) is 7-8 hours, only slightly less than younger adults. However, older adults often experience lighter, more fragmented sleep and spend less time in deep sleep stages. This is a normal part of aging but can be worsened by medications, pain, and sleep disorders. A supportive mattress becomes more important with age as joints and muscles need consistent pressure relief.
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