Sleep Length Myths: Is 7 Hours of Sleep Enough?
We’re used to being told that we need to get 8 hours sleep a night, but the science is far more nuanced. In this FAQ we’ll look at common sleep myths and find out why individual sleep needs outweigh arbitrary hourly targets, how brain function suffers even with almost-enough sleep, and why ‘catching up’ on weekends isn’t the answer. Spoiler: Sleep quality and consistency as much as quantity.
Is 7 hours of sleep enough?
For most adults, 7 hours is the bare minimum for physiological health – you’ll function, but you may struggle to thrive. Experts say 7–9 hours of quality sleep. is the sweet spot. Consistently getting under 7 hours raises your risk of heart disease, illness and cognitive decline. If you get 7 hours, wake feeling wrecked and need caffeine to survive the day, you definitely need more sleep!
What is the bare minimum sleep needed?
People with rare ‘short sleeper’ genes (DEC2 gene mutations) may be OK with 4-6 hours’ sleep a night. But for 99% of adults, consistently getting less than 7 hours nightly will leave us feeling like we’re running on empty. Chronically sub-6 hours sleep increases mortality risk by 14 – 34% and is linked to obesity, diabetes and cardiovascular damage.
Is 6 hours of sleep enough?
For 99% of adults, no. 6 hours sleep isn’t enough, and can cause significant neurobehavioural impairment over time. Focus wavers, problem-solving creativity dips, memory recall is slower, and reduced emotional regulation will mean even the little things irritate you. Studies show reaction times slow measurably, and the accumulation of waste proteins in the brain can cause cognitive impairment, and even accelerate dementia. None of which is ideal when you need to be a functional human being!
Why do doctors recommend 8 hours of sleep?
Doctors say 8 hours sleep is important because it’s a solid average required for peak performance. And it’s easy to remember! In reality some people will be fine with 7, and some will be better with 9. Most people underestimate their sleep by 30–60 minutes: listen to your body, don’t watch the clock too closely!
Does a 15 minute help? Does a one hour nap help more?
A good nap can act like a system reboot. Short 10-20 minute naps boost alertness and mood, which can be particularly helpful in that post-lunch afternoon lull. Longer 60-90 minute naps can help with creativity and problem solving. But nap too long – anything over 90 minutes is inadvisable – or after 3pm, and you’ll wake groggy and potentially mess with your night time sleep.
Is it better to sleep for 1 hour or have no sleep at all?
One hour’s sleep is better than no sleep at all, but it’s still not great. Naps function as a brain reboot, so can relieve sleep pressure (your homeostatic sleep drive). This will help you feel more alert – temporarily – and reduce the risk of involuntary microsleeps, which is why experts recommend you pull over and take a nap if you become drowsy while driving. However, if you wake from your nap midway through a sleep cycle you’ll likely experience heightened sleep inertia and feel worse than before. If you have to nap for safety or just to be able to function for another couple of hours, aim for a 20-minute power nap to avoid deep sleep, or a longer 90-minute nap to ensure you complete one full sleep cycle. And none of this is a substitute for getting a proper night’s sleep…
Can you make up for sleep debt?
Sort of, but not perfectly. A weekend lie-in can help you feel a bit more alert after a rough week, but the debt from chronic sleep deprivation isn’t paid back so easily. It takes 4 days to make up for 1 hour of lost sleep. Catch-up sleep may reduce inflammation but can’t reverse the damage caused; your only recourse is to gradually increase your sleep to 7-9 hours and keep it there.
