Sleep Corner: Circadian Rhythms and Routines: Cultivate Consistency for Improved Mental Health
Circadian rhythms often come up when talking about flying through time zones and experiencing jet lag or after you’ve pulled a grisly all-nighter; however, circadian rhythms are responsible for a wide array of biological processes beyond sleep. The phrase “circadian rhythm” is used to describe any operation in your body that runs on a 24 hour cycle; for example, your digestive system is coordinated through a circadian rhythm that minimizes activity in the evening to help you sleep through the night, and your endocrine system manages the release of hormones on a circadian cycle to help you stay alert and expend your energy efficiently throughout the day. A lesser known fact is that circadian rhythms also govern many of the processes responsible for our mood and mental health, and regulating our circadian rhythms can be fundamental to improved well-being. The takeaway? Sleep is important, and consistency is key.
The reason circadian rhythms are so closely associated with sleep is probably because of something in the brain called the suprachiasmatic nucleus, or SCN. It’s a cluster of about 20,000 nerves in the hypothalamus also known as the “master clock” or “circadian pacemaker”, and this part of the brain coordinates all other circadian rhythms throughout the body, including those responsible for regulating our mood. The SCN is highly sensitive to light, and uses this as its main cue for guiding our biological processes. In addition, the SCN is directly responsible for our sleep cycle. Exposure to light during the day causes the SCN to generate signals to promote alertness and wakefulness; reduced exposure to light in the evening causes the SCN to initiate the production of melatonin to help us fall asleep. Disruption to the circadian rhythm in the SCN is associated with poor sleep and insomnia, in addition to effects that permeate throughout the body: memory issues, fatigue, disrupted hormone cycles, digestive complications, and increased feelings of depression and anxiety.
Research is just beginning to parse out the relationship between disrupted circadian rhythms and mental health. Correlational studies have demonstrated that night shift workers, who are believed to have chronically disrupted circadian rhythms, face greater risks of mental health challenges; scientists have also observed that seasonal reductions in the length of daylight can result in feelings of low mood and depression known as Seasonal Affective Disorder (SAD), and this is believed to be due to a circadian shift. While your circadian rhythms can be disrupted from things like changing time zones or working night shift, drastic changes in sleep and sunlight exposure from waking up early during the week and sleeping until late on weekends (known as “social circadian rhythm disruption”) can also negatively impact your cycles.
The key to maintaining healthy circadian rhythms is good sleep and a consistent sleep schedule— going to sleep and waking up at similar times each day (even weekends) can help your body stay on track. Avoiding artificial light in the evening, which can disrupt your SCN, can also help. Not only will your sleep and energy levels stay relatively consistent throughout the week, but the neural systems responsible for your mood— your limbic brain regions (responsible for feelings of anxiety and motivation, among other things) and monoamine neurotransmitters (responsible for mood hormones like dopamine and serotonin)— which also run on daily cycles, will likely stay better regulated too.
Beyond the biological benefits, there are also concrete psychological advantages to keeping a consistent daily routine. If you struggle with anxiety, planning out your days and scheduling when you’ll accomplish certain tasks can reduce feelings of uncertainty and overwhelm. Reducing the amount of decisions you have to make about your next steps— where you’ll go for lunch, when you’ll call your mom, when you’ll start your homework— can preserve cognitive energy for more important tasks. If you struggle with executive functioning, creating routines can also help you get tasks done as they become habits— doing laundry every Sunday at the same time, for example, can reduce the activation energy required to get it done because it’s built into your schedule and you’re used to doing it at that time.
Having a routine can help you feel more in control of your time, and also means you can deliberately make time for the things that are restorative to you— time with loved ones, time for exercise, and time for your passions and hobbies. If you regularly plan rest and fun into your schedule and hold to it just like any other commitment, you’re also less likely to burn out or work yourself to exhaustion, and can ensure that your mental, emotional, and physical needs get met during the week.
That being said, forming habits is hard, and the process can be slow and frustrating. It’s wise to try to add new routines to your schedule one at a time— not try to revamp your entire life overnight. Be sure to be kind and compassionate towards yourself along the way, and reward yourself when you stick to a habit or routine for a day— oftentimes the pressure to adhere to a habit perfectly can be the biggest obstacle to sticking with it.
Just as consistent sleep at night will restore your body (and keep your circadian rhythms functioning optimally), you can work things into your day that will restore your heart and spirit. Take some time in the morning to really savor your coffee, or meditate for 5 minutes before you start your day. Plan breaks in your study sessions, and make time for relaxation and social interaction. Marty Nemko once said that “routines provide an anchor of predictability” in the unpredictability of modern life.
If you can cultivate consistency in your daily life, your body, sleep schedule, and neurotransmitters will likely thank you.
- Sleep Soundly: A Closer Look at Melatonin The Flourish, April 2022: Sleep Corner
- Better Sleep - Sleep Hygiene Tips Stanford CAPS, Ariana Davidson LCSW
- Time Management Tips Stanford Learning Lab
- Why your sleep and wake cycles affect your mood Harvard Health Blog
- The secret benefit of routines. It won’t surprise you. Headspace
- Do you need to reset your circadian rhythm? Cleveland Clinic