How to nurture your circadian rhythm
Your circadian rhythm (sleep-wake cycle) is fundamental to optimal health. People who live in harmony with their circadian rhythms experience improved insulin sensitivity, better sleep, less stress and improved mood (1). And they tend to lose weight more successfully (2). A regulated circadian rhythm is also associated with improved fertility in women (3). In a nutshell, hormones crave rhythm.
Circadian rhythms are physical and behavioural changes that follow a daily cycle. They mainly respond to light and darkness in our environment. Sleeping at night and being awake during the day is an example of a light-related circadian rhythm.
Our circadian rhythms are very sensitive to disruption, mainly because of how we process light. Humans have a group of nerves directly behind our eyes called the SCN, which send signals to our master clock, the pineal gland. The pineal gland is responsible for making melatonin, that all important sleep hormone. When it gets dark, the SCN tells the pineal gland to start pumping out melatonin and we start to feel sleepy.
The SCN are extremely sensitive to light changes; going to bed just an hour later will disrupt them. As a general rule, it takes an entire day for your body to adjust to going to bed an hour later.
The problem with artificial light
Added to this, we evolved at a time when our only sources of light were the sun and a campfire. Fast forward to 2020, and our systems are unsure how to cope with all the artificial light we are exposed to. Your brain can be easily tricked into holding back on melatonin production at 11pm because it thinks it might still be daytime.
It’s kind of heartbreaking when you think about it. Our poor bodies are trying to do their best to maintain stability under very confusing conditions. Be kind to your body and nurture a circadian cycle that your hormones have evolved to understand.
How to restore your circadian rhythm
- Go to bed at the same time every night and get up at the same time every morning, even at weekends. The SCN can remember what happened last night and the night before, so it will take a few days of being strict with yourself to get your rhythm established.
- Get daylight on your skin within twenty minutes of waking. If you’re blessed with some outside space, this could be as simple as standing outside in your pyjamas first thing, to drink a cup of tea. It’s a lovely habit to get into and it really helps you to feel in tune with your body’s natural rhythm.
- Eat your last meal of the day at least three hours before you intend to go to bed. Research shows that circadian rhythms adjust better to sleep when food isn’t available.
- Limit your screen time for at least an hour before bed, or use a blue light blocking app on your phone or laptop. If you have an iPhone, go to Settings > Display > Night Shift and set the time to an hour before you intend to go to bed. Alternatively, invest in a pair of blue light blocking glasses (there are many different brands available from Amazon).
1. Voight, R. et al. (2016). Circadian Rhythm and the Gut Microbiome. International Review of Neurobiology. 131. pp.193-205.
2. Becutti, G. et al. (2017). Timing of Food Intake. Pharmacological Research. 125.pp.132-141
3. Evans, M. & Anderson, G. (2018). Integration of Circadian and Metabolic Control of Reproductive Function. Endocrinology. 159(111). pp.3661-3673
About the Author
Julie Hypher is a BANT registered Naturopathic Nutritional Therapist and founder of Wildwood Nutrition, a dedicated nutritional therapy clinic in Hamble, Hampshire. She runs private Clinics every Tuesday and Thursday.