Our bodies are designed to be active during the day and to get into a restore or reprogram mode during the night. Our sleep-wake cycle is controlled by an internal body clock known as the circadian rhythm. This biological clock is the reason we tend to feel energized, drowsy or hungry around the same time every day.
Sleep disruptions and a chaotic sleep-wake cycle can negatively affect our health, especially our immune system and short-term memory. Light is such a powerful cue for the biological clock that bright lights at night can seriously disrupt your circadian rhythm. Bright street lights, the light from television or mobile phones and even LED lights from your bedside clock can disrupt your sleep rhythm.
Many of us tend to stay up late at night, with bright lights, working on our projects or reading late into the night. People who alternate their shifts or work night shifts often suffer from chronic insomnia symptoms.
Research reveals that you never become truly accustomed to working during the night as your biological clock knows you’re supposed to be sleeping at that time. Constant disruptions to our circadian rhythm can lead to a variety of health issues such as sleep disorders, ulcers, and heartburn.
The circadian rhythm follows the 24-hour rhythm of the sun. The presence or absence of light is the primary cue for our internal biological clock. When daylight changes to night and vice versa, these light cues are taken in by the retina in the eyes.
Melatonin levels in our body rise when darkness falls, so you feel tired and sleepy. When the sun rises, our melatonin levels drop. Then we feel awake and mentally alert. The circadian rhythm is not just limited to controlling sleep routines. It directly affects other essential drives such as hunger, thirst, and body temperature.
Some people prefer to get up very early in the morning and go to bed early too, while some feel more energetic at night and find themselves working until late. Such people often find it difficult to get up early in the morning and they may feel tired or sluggish if they do. Your personal circadian rhythm is known as your ‘chronotype’. If your chronotype is that of an early riser, you will probably be feeling more energetic and productive in the mornings than in the evenings.
The 24-hour biological clock, based on the rhythm of the sun, is coded into our genes and it is our body’s most natural rhythm. Following this sleep-wake cycle and allowing our bodies to function according to their own pace improves our physiological and psychological functions on a daily basis. This positively impacts our short term and long-term health.
Jet lag is a common circadian rhythm sleep disorder that occurs when you travel across multiple time zones. You may feel tired and sleepy during the day and more alert a night as your circadian rhythm may still be aligned with your former time zone. Thankfully, this condition gets resolved within a day or two. But constantly confusing your body clock can cause your health to suffer and over time, this can lead to chronic health disorders.
Disruption in circadian rhythms can alter nerve functions and cause neurological disorders. Night shift work, repeatedly working late into the night, over a long period increases the risk of :
Circadian rhythm disturbances can also cause:
There is increasing evidence that disruption of circadian rhythm is associated with increased risk of many serious health complications such as:
To avoid the negative health effects of circadian misalignment and in order to get adequate amounts of healthy sleep, it is important to align your sleep schedule with your own unique body clock.
Irrespective of whether you are an early riser or not, here are some tips to shift your internal clock and greet the day bright and early.
You may find it difficult to break old habits and form new ones. It may take a few weeks or even a months to establish a fresh sleep-wake routine. It is important to be consistent so that you can reap the many mental and physical health benefits of being in sync with your natural circadian rhythm. You will feel healthier, mentally alert, energetic and more productive, to name just a few of the benefits.
Originally written 19th September 2019