Hickory Dickory Dock, the Internal Body Clock

Circadian Rhythm Makes a Person Feel Sleepy or Stay Awake

Alarm clocks, alarm set in your smartphone or your mom/dad waking you before a big interview or exam is a regular affair for most. How many of you are aware that our body has its own internal network of clocks that makes us sleepy as the moon peeks out between the clouds, get up from bed as the sun shines or feel hungry when it is close to lunchtime? Circadian rhythm is our body’s 24-hour internal clock that keeps working continuously helping us shuffle our sleep/wake schedules and hence, known as the sleep/wake cycle. This circadian rhythm is present in every living being, including plants, animals, fungi and cyanobacteria.

Have you ever thought why we stay awake and alert when the sun is shining and feel sleepy or drowsy when it’s dark outside? That’s because this complex timekeeper is controlled by the brain portion that responds to light and influences the body greatly.

The Story of Circadian Rhythm
Our brains hold the ‘master clock’ which receive inputs from the eyes and coordinate all other biological clocks in the body. The eye signals the brain to produce hormones that help an individual stay alert, awake, energized and boost your heart rate during the daytime and as the sun sets, it signals the brain to produce melatonin hormone that helps you feel drowsy and sleep well.

All our day-to-day activities such as sleeping, waking, eating and even going to the bathroom function based on this 24-hour cycle. For instance, most people feel sleepy between 1.00 p.m. and 3.00 p.m. and again between 2.00 a.m. and 4.00 a.m., but this is not mandatory and can vary from person to person. That’s why some people love to stay up late during the night while others feel brisk in the early morning hours. Every individual’s biological clock’s settings are determined by specific genes which can have a strong impact on the body temperature, blood pressure, energy level, inflammation, fertility, mood and brain functions. Some people are likelier to experience a heart attack during the early-morning hours due to increase in the level of a hormone called cortisol. Research also shows that late night owls are at an increased risk of heart attack and if you are one of those who tends to stay late during the night, try to get rid of this habit. For more information on this, please visit the website www.firsteatright.com. This also brings us to the point where eating habits affect body weight. Research has proved that eating late in the night, close to when melatonin is released, can affect the normal circadian rhythm leading to increase in body fat, weight gain and tiredness resulting in obesity, heart disease and diabetes.

Modern-day Stressors that Affect Circadian Rhythm
Presently, we do not follow the ‘Early to bed & early to rise’ principle due to various reasons. It might be due to our own requirements of watching late-night TV shows or fidgeting with our smartphones. Some people are forced to stay up late due to different shift schedules. These shift workers have their entire biological cycle turned upside down and might be tired at work or unable to sleep during the daytime when the sun is shining brightly. Even studies show that shift workers have increased risk of heart disease, digestive disturbances, cancer, depression and other health problems.

Jet lag is another classic example for disrupted body cycles. The different time zones in different countries can impact our circadian cycles and make the brain extremely tired and troubled trying to adjust when the time of day changes suddenly.

Researchers are trying to explore various options on how to sync-up the body’s clocks to the body’s health. They are even analyzing the best time to have a surgery on specific parts of the body.

Circadian rhythm might change as you grow older and you might have a totally different sleep/wake cycle from your partner, children or parents. Only when you introspect on your body cues and adjust your sleep hygiene habits, will you feel alert and better.
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If you follow your body’s internal cues to go to bed/wake up, your circadian rhythm stays balanced and you find no trouble doing your chores. But, any change in schedule such as shifts or jet lags can totally disrupt your 24-hour cycle and you need to readjust certain things to keep your circadian rhythm functioning as it should:

Set sleep rules: While a constant bedtime time is best for the health, getting up at the same time every morning can also do good to your circadian rhythm. Enjoying some extra hours of sleep during the weekend might seem inviting, but this can throw off your body clock during the week days.

Practice early-morning activity: Exposure to sunlight helps set your circadian rhythm correctly apart from providing you with energy. A quick walk in the early sun indicates your brain that it is time to start your day. If you don’t have time for this, just peep out of your balcony and enjoy some sunlight or at least raise the blinds or switch on the brightest light in your house.
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Minimize gadget use in the evening: Darkness makes us feel sleepy and bright lights post-evening can create a false situation confusing the brain that its still daytime. Artificial blue light (found in laptops, tablets and smartphones) is the worst of all and it is better to switch off all your gadgets and spend some time quietly, at least 2-3 hours before bedtime.