Described by biologist Dr Satchidananda Panda as the next revolution in healthcare, research into our circadian rhythms certainly seems to be gaining attention. In fact, this field of study was recognised with a Nobel Prize in 2017 for its impact on human health, and the use of chronotherapy (where medication is administered in accordance with our circadian cycles to be more effective) is growing increasingly popular. But what exactly are these natural rhythms and how can we use them to improve our wellbeing? “The term circadian comes from the Latin circa, meaning ‘around’, and diēm, meaning ‘day’,” Dr Panda explains in his new book The Circadian Code (Vermillion, £14.99). “Circadian rhythms are real biological processes that every plant, animal and human exhibits over the course of a day. These rhythms are actually interconnected among species and are governed by internal circadian or biological clocks. Almost every one of our cells contains one of these clocks, and each is programmed to turn on, or off, thousands of genes at different times of the day, or night.”
In other words, we’re naturally predisposed to do certain things at certain times of the day and our bodies’ systems work in harmony with this. Most advice about our circadian rhythms focuses primarily on our sleep and wake cycle and although this is one of the most important aspects of our internal algorithm, this largely overlooks the impact our circadian cycles have on all areas of our life.
As integrative health, nutrition and wellness coach Jules Anderson (feelglorious.com ) explains, different organs and body systems (such as our circulation, digestion, muscle strength and brain acuity) operate and peak at different times due to our circadian rhythms. Essentially, our body can’t do everything all at once and so we have a meticulous internal schedule which runs over a roughly 24-hour period.
“Living life against this natural rhythm requires effort and causes our body to operate less efficiently – all of which will contribute to tiredness, ageing and inefficiency, which may ultimately lead to disease,” Jules adds. “On the other hand, if we align the way we live with the way our bodies were designed, we will see improvements in our sleep, digestion, focus, energy levels and mood. And this can help us to lose weight, feel less stressed and reduce the incidence of chronic illnesses like cancer, heart disease and diabetes.”
So how can we live in tune with our circadian rhythms and improve our health?
Understand your internal clock
The first step to living in tune with your cycle is to understand it. One of the primary influences on our circadian rhythms is the rising and setting of the sun (which impacts levels of the sleep hormone melatonin and supports our sleep and wake cycle), but there are other things that affect them too – such as the timing of food and activity. They do their best to adapt to what we’re doing on any given day but if we regularly change our routine, our clocks become confused and this can have drastic consequences for our wellbeing. That’s why, according to experts, one of the best things we can do to support our health is to go to bed, wake up, and eat our meals at roughly the same time every day.
Spend time in daylight
As mentioned already, light has a key role to play in regulating our circadian rhythms. “When daylight enters our eyes, it stimulates a special light sensor, which connects to the brain, triggering the release of hormones and causes our bodies to wake up and feel alert,” Jules explains. “It also causes melatonin to decrease. The more active we are during the day, the more robust our biorhythms will be, the stronger our body systems are and the less we will need to rely on coffee and sugar. If you spend time in daylight, your body will naturally sleep at the correct time, too.” Artificial lights, on the other hand, can disrupt our bodies’ messages and lead us to believe that it’s daylight when it’s not – which can result in difficulties sleeping. Try to spend as much time in natural light as possible and resist having bright artificial lights on late at night or using screens too close to bedtime. Going for a walk first thing in the morning is also a good way of kick-starting your circadian rhythm for the day.
Remember the importance of sleep
“Our bodies have trouble adjusting when we have not slept enough, and the complexity of life can cause us to disrupt our preferred circadian rhythm,” explains Dr Audrey Tang, a chartered psychologist and the author of The Leader’s Guide to Mindfulness . “If we are sleep-deprived this can result in irritability, an inability to think rationally, as well as a lowered immune system. Sleep is also our body’s opportunity to repair and it plays a role in regulating the production of some hormones important for health.” Try to keep a regular sleep schedule whenever possible (even at the weekends) and allow time for quality shut-eye. This means giving your body the cues it needs to prepare for night time – a proper wind down routine, a dark and relaxing environment and no stimulants such as caffeine or a heavy meal before bed.
Eat your main meal before 3pm
Many of us choose to eat light meals for breakfast and lunch, and gorge on larger dishes in the evening, but this could be working against our bodies’ rhythms. “Our digestion is naturally strongest in the middle of the day, so eating our largest meal at lunchtime allows the body to more effectively digest our food, turning it into energy – not fat,” Jules explains. “If we eat when our digestion is slower, we won’t metabolise completely, our body can get clogged and we can get sluggish, constipated and store fat. Also, our bodies can’t sleep deeply if they are still trying to digest late night food.”
Fast for 12 hours every night
As Jules explains, digestion takes a lot of energy. Her advice is to eat early in the evening and then fast for 12 hours. “This allows our final meal of the day to fully digest and our digestive system to rest,” she explains. “This period of rest and repair is essential as otherwise waste products can build up in our bodies and not be fully processed.” Dr Panda agrees. His research on time-restricted eating shows that eating in a 12-hour period can have a huge benefit for your health, helping you sleep better, have more energy and lose weight too, and these benefits are even more apparent if we restrict our eating to just eight hours a day.
