Could poor sleep cause depression?

Just last week was Bell Let’s Talk Day, where Bell donated more than $6 million to mental health support and research.  On my social media, the screen was filled with people talking openly about how they’ve suffered from mental illness including depression. Some stories so sad, as a close friend lost a family member this month to the effects of mental illness. So heartwarming, as so many seem to be finding the help and support they need to be strong and fight disease.

I am so fortunate that mental illness hasn’t been a part of my family’s experience to this point. What I feel this allows me to do is take a step back and view mental illness, specifically depression and anxiety, in an objective way.  Some may argue that I could never really understand because I haven’t lived it myself…and in some ways, I do agree. But as a medical practitioner (even only a “dentist”) this lack of personal experience allows me to research non-judgmentally.

After more than 20 years in dental practice, I find an alarming increase in the  reporting of the use of medications to treat mental illness in the medical histories of my dental patients. This reporting includes medications taken as early as preteens, even 9 and 10 years old! I find this so frightening, wondering what is happening to us as a society that mental health diagnoses are seemingly coming in increasing numbers. It makes me, and thankfully very smart researchers, extremely curious. During dental school, we are taught to fix the problems of the teeth, but over the years I’ve also learned that fixing the problem is great but can be useless unless we understand what caused the problem in the first place!

There have been numerous studies done that link depression and anxiety to poor sleep quality. This makes complete sense…think about how you feel when you stay up late for an event or an all-nighter to study in school.  Your brain the next day at work or in school after that big exam is like mush.  You can’t think properly, you feel nauseous, drink too much coffee, you are crabby and irritable…wow! Now imagine that every single day you get inneffective sleep, your brain not getting enough time in the restful, healing portion of our sleep, our bodies not having the proper time and oxygen to repair from the things we did to it all day long. Day after day, this changes you, changes your whole outlook on life. Now…get an amazingly restful night of sleep after a long work week…you feel fantastic! Why? Because your body and brain had sufficient time and sufficient oxygen during the night to heal.

Sleep and depression, is it the chicken or the egg? Many sufffering from depression or anxiety will say they can’t sleep because they are depressed or anxious, but I’m not so sure. A medical colleague, Dr. Steven Park, dedicates every single blog he writes to sleep disorders, their links to systemic disease, and solutions. The one I’ve linked to here describes in detail how the sleep disorder may actually come first and was written just after actor Robin Williams’ untimely death this summer. In fact, when I have patients who report taking medication for anxiety or depression, one of the first questions I ask is if they’ve had a sleep study to rule out a sleep disorder.  What I can tell you is that 100% of the time that I ask this question, the answer is…no. Wow. What this tells me is the doctors are addressing the immediate problem but not investigating what could be the underlying cause!

So, while I am not responsible nor trained for the treatment of depression or anxiety, I can still make recommendations about how to investigate the cause. Here is my recommendation: get tested and treated for possible obstructive sleep apnea or upper airway resistance. From the dental perspective, having narrowed jaws and dental crowding prevents proper breathing at night while sleeping. Poor sleep in general has been found to lead to weight gain, which can narrow the throat even further. Not getting good sleep (especially deep sleep) can definitely cause symptoms of anxiety or depression. The rate of undiagnosed obstructive sleep apnea is so high (~80%) that it should be a mandatory test for everyone, just like testing for high cholesterol or high blood pressure. A sleep study can be done through a sleep laboratory, and in Canada your physician would make the referral. The other way is to do a home sleep test screening, and we “rent” out this device from our office for a two night sleep study in the comfort of your own home.  Either way, this is such an important diagnostic test that I can’t think of a single patient who shouldn’t do this!

Dr. Andrea Stevens is a cosmetic and family dentist in practice in Kanata, Ontario. If you have dental questions, you can call her at 613-271-7091 or visit her at Please also feel free to leave comments or questions below, and Dr. Stevens will be happy to answer!