Why sleeping more than 9 hours could actually be damaging your health

Sleep is one of the most important factors for our well-being, and many of us worry that we’re not getting enough, but is there such a thing as too much sleep? According to experts, the answer is yes.

Regularly sleeping more than nine hours a night can not only increase your risk of various mood disorders or metabolic issues, but it can also mess up your circadian rhythm. The occasional lie-in or early night isn’t going to cause any issues, but what does it mean when you frequently feel that the recommended average of eight hours of sleep isn’t enough to help you feel rested and restored?

To get all the answers to our sleep-related questions, we caught up with Dr Jeffrey H. Chester, a physician and Medical Director at The Ohana Luxury Addiction Treatment Center, and it might make you rethink those lazy weekend lie-ins…

What is the optimal amount of sleep for adults?

Firstly, it’s good to understand how much sleep you actually need each night to best support your well-being. Dr. Chester explains: “For most adults, there is an optimal range. And that range is between seven and nine hours a night.

“This amount of sleep is associated in clinical studies with optimal cognitive function, physical health, and emotional regulation. It’s okay to be a little outside of that range.”

Can you sleep too much, and what happens when you do?

According to the doctor, it is possible to oversleep, and it will do more than simply make you feel a little groggy. “It is possible to sleep too much. Oversleeping, which is consistently sleeping more than nine or ten hours a night, has been associated with mood disorders, fatigue, and brain fog. There is also a higher risk of conditions like metabolic issues and heart disease,” he says. 

“Many people think that excessive sleep would be deeply restorative. However, it actually interferes with the body’s natural circadian rhythm. This can impact energy levels and cause fatigue.”

When to be concerned

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So, what is the difference between catching up on sleep every now and then, or a cause for concern? “If a person is consistently sleeping nine or ten hours a night or more, then it’s a good idea to talk to a doctor or healthcare provider,” Dr. Chester shares.

He adds that sleeping a little longer is normal if you’re recovering from illness, but you should seek expert advice if you’re regularly oversleeping or feel like you are much more tired than usual. “Occasionally sleeping longer, such as after being ill, is fine. But if a person is consistently sleeping more than nine hours a night, it’s time to talk to a doctor.”

Support for a healthy sleep routine

As a health and wellness coach, I’ve learned that establishing a sleep routine can be incredibly beneficial for your well-being and even improve the quality of your sleep, meaning you will likely feel less need to lie in or oversleep to catch up on rest. Simply set a regular time that you go to bed and wake up each day, even on weekends, and your circadian rhythm will start to naturally wind down and prepare for sleep ahead of this time on an evening, and help you wake more easily in the mornings.

You may also be surprised to learn that seeing more daylight can also impact your quality of sleep. Exposure to bright natural light – particularly in the early morning and late afternoon – can help to influence the release of the sleep hormone melatonin, and prepare your body for restful, quality sleep. 

Your evening routine is incredibly important, too. Introducing some relaxing rituals can go a long way to supporting your sleep, taking you out of fight-or-flight mode when you’re feeling stressed, and activating your parasympathetic nervous system so you fall asleep more easily. This is a topic I’ve covered in detail in my book, Good Evening Rituals, with examples including meditation, journaling and simply being more mindful while doing your nightly skincare routine or brushing your teeth.