We hear a lot about how much is too little sleep and what that may mean for our health, but what about the other end of the scale? What is the maximum number of hours of sleep for good health?
To cut straight to the chase, a study of over half a million people found that sleeping too little but also sleeping too much can increase the risk of heart attack.
Those who took part in the study who slept for less than six hours per night, when compared to those who slept between 6 and 9 hours were 20% more likely to have a heart attack. But those that slept more than nine hours per night increased their risk by 34%.
The same research found that those that were at a high genetic risk of heart attack could compensate for that risk by sleeping between 6 and 9 hours. This cut their risk by 18%.
We hear a lot about sleep deprivation increasing the risk of not only heart attack but also diabetes and hypertension, which can lead to stroke. An investigation which reviewed several studies into sleep duration found that sleep duration is linked to hypertension, coronary heart disease and diabetes and concluded that “Sleep periods that are neither too short nor too long may be important to keep us healthy,” and again reported that less than 6 hours is not good. More than 9 hours is not great either.
It seems that there is a maximum hours of sleep for good health and the risks are similar, although in some cases higher, than if we sleep too little. But there’s more to it than that. We’re all different when it comes to sleep and some of us need more than others, but how do we know when we’ve slept for too long and if we do sleep too long, what might it mean?
How do you know if you’ve slept for too long?
If you still feel tired and sleepy after a long sleep the chances are you’ve slept for too long. But other factors may be contributing to the reason that you want to sleep for a long time each night.
Oversleeping can be a marker of depression. Disrupted sleep is not only a symptom of depression but also contributes to it.
When we’re struggling to deal with our emotions our brains try to help us by making sure we have more REM sleep. This is our body’s way of working through our emotions by using dreams. However, when we’re depressed our dreams can be so big that they wake us. For this very reason, depression is also associated with early morning waking which can lead to our want and need to sleep for longer.
Sleep disorders can also be a reason that you’re sleeping for a long time. The quality of sleep when you have a sleep disorder can be reduced and so we find we want to sleep for longer but still feel tired during the day.
Obstructive sleep apnoea and restless leg syndrome are two possible reasons you want to sleep for longer. Sleep disorders can disrupt your sleep, whether you’re aware of it or not. But sometimes there is no cause, and when you sleep for a long time and feel tired during the day this is called Idiopathic hypersomnia.
Other things that may cause you to sleep a lot can be some medical conditions, types of medications and also use of alcohol and drugs, which disrupt sleep and our circadian rhythm.
What to do if you’re sleeping for more than the maximum hours of sleep for good health?
When you sleep too much, the best thing to do is to stick to a regular bedtime and waketime each day. This allows your internal clock to get into a rhythm. Also, seek professional help. Visit your GP to find out if there is a possible underlying reason for your need to sleep for a long time. Especially when you still feel tired and sleepy during the day.
Everyone is different and our sleep needs are different too. How active we are, if we’re stressed, our genetics and our health all influence our sleep needs and how well we sleep. For this reason, there’s not a one size fits all when it comes to sleep. However, according to studies over 9 hours seems to be the red flag moment which can signal other issues, especially if you’re still feeling sleepy and tired during the day. So the maximum hours of sleep for good health? Studies point to 9 hours.
To read more about dreams and how they help us process our emotions ope over to the January issue of the SLEEP magazine. It’s FREE!