In the era of nutritional and wellbeing awareness, it's no secret that all the processes of the body are interconnected. 

Experts up till now have identified strong evidence to suggest that eating habits are crucial for the quality of sleep. 

But what about the other way round?

Could your sleep quality, duration, and hygiene affect how much you eat?

Sleep and Hunger Hormone

The hunger hormone found in our body is called Ghrelin.

Its main function is to increase our appetite and induce the feeling of hunger.

Ghrelin also regulates glucose homeostasis (blood sugar regulation) and promotes fat storage. 

On the other hand, a hormone called Leptin induces satiety or the feeling of fullness.

The levels of both these hormones significantly influence your eating habits.

Image: Hunger-regulating hormones

Research has shown that sleep patterns influence ghrelin levels. 

When a person is asleep, the body reassures the brain that the existing energy levels are sufficient for the time being.

Hence, the ghrelin levels decrease, and at the same time, leptin levels rise.

A study has found a significant association between sleep duration and leptin and ghrelin levels, independent of age, sex, BMI, and other confounding factors.  

A single night of disrupted sleep increases ghrelin levels and typically has no effects on leptin levels.

However, chronic sleeplessness results in the fall of leptin levels as well.

According to a report in the journal of the Public Library of Science, those who consistently slept for 5 or less hours a night had a significantly different profile of the hunger hormones than those who consistently slept for 8 hours.

These changes in the hormone levels ultimately lead to increased hunger and excessive eating, all of which may result in weight gain and obesity. 

An Extra Hour Of Sleep Can Help Lower Calorie Intake

A randomized clinical trial was conducted to examine the effects of sleep extension on energy intake among overweight adults.

The results, published in JAMA Internal Medicine on the 7th of February, reported that the participants who slept for an extra 1.2 hours (72 minutes) per night reduced their energy consumption by 270 kcals per day.

Details of Study Participants

The Study Methods

The participants used an accelerometer-based monitor with an event marker to record their sleep-wake patterns.

During the 2-week baseline, the participants followed their habitual sleep duration.

At the end of two weeks, the participants chosen for sleep extension underwent a counseling session with a sleep hygienist.

The study investigators then advised this group of participants to extend their sleep duration to 8.5 hours. 

On day 22, the participants returned for a brief follow-up and counseling session (if required).

The energy intake and storage were measured using the doubly labeled water method, a urine-based test. 

The Study Results

• Participants belonging to the sleep extension group had a 1.2-hour increase from the mean sleep duration - compared to those in the control group.
• Sleep efficiency remained the same between both groups.
• Energy intake was significantly reduced by 270 kcal per day in the sleep extension group.
• Each 1-hour increase in sleep duration corresponded to a reduced energy intake of approximately 162 kcal per day.
• The participants in the sleep extension group also experienced a significant weight loss (avg. 0.87 kg) compared to the ones in the control group.

The Takeaway

Sleep is a vital part of maintaining a healthy lifestyle and preventing a plethora of diseases.

Those who habitually sleep for seven hours or less can benefit in terms of weight loss when they extend their sleep duration.

Summary

1. Ghrelin, the hunger hormone, and leptin, the satiety hormone, play an important role in regulating eating behavior.
2. Acute sleep disruption leads to increased ghrelin levels, and chronic sleep disruption leads to reduced leptin levels and increased ghrelin levels.
3. A study published in the JAMA Network reported that increasing sleep duration by 1.2 hours can reduce energy consumption by 270 kcal/day in individuals who are habituated to <7 hours of sleep.

References

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC535701/
2. https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0010062
3. https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2788694

Abstract

Night shift work can impact your circadian rhythm by making you operate in a way that is “unnatural” to your sleep-wake cycle. A recent study has reported that people who work night shifts are at an increased risk of developing atrial fibrillation and heart disease. The study further reported that among the night shift workers, women who are physically inactive are at the highest risk.

What is Atrial Fibrillation?

Atrial fibrillation (AF) is characterized by irregular and often rapid heart rate that can increase the risk of stroke, heart failure, and other heart-related ailments.

Generally, the chambers of the heart work in coordination to pump the blood. However, in AF, the two upper chambers of the heart (right auricle and left auricle) beat chaotically and out of coordination with the two lower chambers (right and left ventricle) of the heart. 

Some common symptoms associated with AF include :

• Pain in the chest
• Dizziness
• Fatigue
• Shortness of breath
• Fast heart rate or palpitations

Learn Your Genetic Risk for Atrial Fibrillation with Xcode Life’s Gene Health Report

Night Shift And Heart Disease

Night shift workers, on average, get two to three hours less sleep than other workers. They often sleep through the day in two split periods; a few hours in the morning and then around an hour before starting the night shift. 

It’s challenging to keep the sleep environment dark, free of noise, and relatively calm. A person working the night shift is at greater risk of various health conditions due to the disrupted circadian rhythm.

Researchers suggest that working the night shift may lead to hormonal and metabolic changes, which can increase the risk for obesity, diabetes, and heart disease.

Further, studies report that circadian misalignment results in a drop in levels of the weight-regulating hormone leptin. This can increase heart disease risk by prompting an increase in appetite.

The Study: Night Shift Work and Heart Problems

The study included 286,353 people who were in paid employment or self-employed.

The study cohort was divided into:

• 283,657 did not have AF when they enrolled (out of which genetic information was available for 193,819)
• 276,009 did not have heart failure or stroke (out of which employment history information was provided by 73,896)
• 75,391 who answered a questionnaire about their lifetime employment in 2015
• 5,777 who developed AF in a follow-up time of over ten years

The researchers adjusted their analyses for several factors like age, sex, ethnicity, education, socio-economic status, diet, smoking, body mass index, sleep duration, and chronotype that could alter the risk of developing AF.

The researchers, therefore, adjusted these risk factors.

The following were observed in the study:

• People who are currently working night shifts have a 12 % increased risk of developing AF.
• For those who had a lifetime duration of night shifts, the risk increased to 18% after ten or more years.
• People who worked night shifts three to eight times a month for ten years have a 22% increased risk of developing AF.
• The risk of coronary heart disease for the above three groups was 22%, 37%, and 35%, respectively.

The study further revealed two more interesting findings.

• Women had a 64% increased risk of developing AF than men when they worked night shifts for ten or more years.
• People who performed 150 minutes of moderate-intensity physical activities or 75 minutes of vigorous-intensity activities per week had a lower risk of developing AF.

How To Work The Night Shift and Stay Healthy

Avoid Caffeine Close to Bedtime

Caffeine inhibits your body’s ability to feel sleepy. So, avoid food and drink containing caffeine at least 4 hours before your bedtime.

Maintain A Sleep-Conducive Environment In Your Bedroom

Light exposure can activate all the processes in your body associated with wakefulness, making it difficult for you to fall asleep. Use blackout curtains or blinds that can help block the light entry.

Eat Healthy

Shift work has been associated with an increased risk of metabolic disorders. Limit sugar intake and increase protein intake. Eating small, frequent meals can also help maintain your metabolic health.

Exercise Regularly

Avoid daytime exercising when on shift work, as it can promote wakefulness. But, make sure to adopt a consistent exercise routine as this can help lower the risk for heart disease.

Video

Summary

• Atrial fibrillation is a condition characterized by an irregular and often rapid heart rate.
• A recent study explored the link between night shift work and atrial fibrillation.
• According to the study, people who worked night shifts over an extended period have an increased risk of atrial fibrillation than the day workers.
• Among shift workers, women who are not physically active seem to have the highest risk for Atrial Fibrillation.
• Following a healthy diet, good sleep hygiene, and a consistent workout routine can help maintain your health when on a night shift job.

References

• https://www.sciencedaily.com/releases/2021/08/210816111941.htm
• https://www.heart.org/en/health-topics/atrial-fibrillation/what-is-atrial-fibrillation-afib-or-af
• smart.servier.com

The Science Behind Sleep

The common ingredient in your tea, coffee, and energy drinks, caffeine, is the strongest psychoactive drug in the world. It is not a secret that caffeine helps you stay awake. But, how does it manage to do that?

Let's first look at how your brain puts you to sleep.

Adenosine triphosphate, or ATP, is the energy currency of your body. ATP is broken down into a molecule called adenosine in the brain. Adenosine moves around the neurons keeping up your energy levels throughout the day.

As the day progresses, some of these adenosine molecules exit the neurons and bind to the receptors. This causes sleepiness. There are two adenosine receptors, A1 and A2A. A1 receptors are found on neurons that keep the brain awake, and A2A receptors are found on neurons that initiate sleep. 

Image: Adenosine receptors and sleep

When adenosine binds to the A1 receptor, it reduces the activity of the neurons. When it binds to the A2A receptors, it increases the activity of the receptor. The combination of this binding, along with a few other hormonal changes, makes you sleepy. When you sleep, the adenosine is slowly released from the receptors, and when there isn't enough left to bind to the receptors, you wake up from a refreshed night of sleep.

Caffeine And Sleep

Caffeine and adenosine are similar in structure. So, the caffeine can mimic the adenosine molecules and bind to the A1 and A2A receptors. However, caffeine's structure isn't identical to adenosine. As a result, it doesn't produce the "sleepy" effect.

Instead, it wards off sleepiness by preventing the adenosine molecules from binding and initiating the sleep process.

  Image: Caffeine binding to adenosine receptors

But this effect lasts for only two to four hours, depending on how fast your body can break down the caffeine. This largely depends on your genes. When your body starts getting used to the caffeine intake, it produces more adenosine receptors to counteract the effect of caffeine. You may have to end up consuming more caffeine to stay awake!

Caffeine Withdrawal

Increased caffeine consumption leads to increased production of the receptor, which again results in increased caffeine consumption. It is a pretty vicious cycle that can make you a chronic caffeine drinker! As a result, you eventually develop caffeine tolerance. When you abruptly bid farewell to caffeine, you may end up feeling way too drowsy because of the additional adenosine receptors in the brain. This is called caffeine withdrawal.

Caffeine withdrawal is characterized by other symptoms like:

• Fatigue
• Drowsiness 
• Irritability
• Inability to concentrate. 

They can last up to a week till the number of receptors goes back to normal. Caffeine isn't as addicting or life-threatening compared to drugs like cocaine. People tend to have a mild physical dependence on this drug. People cannot overdose on caffeine easily. An average adult would have to have about 100 cups of coffee, which amounts to 10 grams of caffeine, to experience any lethal effects of caffeine.

The adenosine receptors are also found in the heart and kidneys. Activation of the receptors decreases the activity of these organs as well. Reduced urine output and heart rate prepare the body for a good night's sleep. However, when caffeine goes and binds instead, it results in increased heart rate and urine production. This is manifested as caffeine jitters and dehydration.

Caffeine isn't very dangerous; however, children should avoid it. Scientists haven't understood the effect of caffeine on a developing brain yet. It is also unhealthy for an adult to be consuming too much caffeine. Sleep and rest are essential for healthy brain function and well-being. 

Getting a Genetic Test

The genes that metabolize caffeine can say a lot about how much caffeine is "healthy" for you. A genetic test can help identify your caffeine metabolizing status. 

Xcode Life's Gene Sleep report profiles genes that influence sleep upon caffeine consumption. All you need is your genetic ancestry test raw data to get started!

Video

What Is A Chronotype?

Research shows that your bedtime may actually be linked to your DNA! Everyone’s biological clock is wired differently; it’s not in sync. Environmental and genetic factors affect your circadian rhythm, or your internal clock. Circadian rhythms, in turn, influence your sleeping pattern.  

Your preferred sleeping pattern is called your ‘chronotype.’ Going to sleep around 11 PM and waking up around 7 AM puts you in the average chronotype category. Someone with an average chronotype gets roughly the same amount of sleep on both working and non-working days, and this is good.  

About 40% of the population does not belong to this category. They have late or early chronotypes. These people will find it pretty difficult to go to work after a free day. They may even experience symptoms of jet lag.

What contributes to the difference in chronotypes?

Melatonin: The Sleep Hormone

Melatonin is the "sleep hormone" that regulates the sleep-wake cycle in the body. It is produced by a neuron bundle called Suprachiasmatic Nucleus or SCN for short. 

For people with the average chronotype, melatonin production starts around 9 PM, and the whole body enters into the 'rest mode' by 10:30 PM. The body temperature enters its lowest around 4:30 AM. These people usually wake up around 6:45 AM when the blood pressure spikes to the highest point. They are known as the 'early risers' and are alert and active during the daytime. 

For people with the late chronotype, this whole cycle happens later during the day. As a result, they tend to sleep and wake up much later. 

They may not entirely be able to fix this. This is because the CLOCK genes found in the SCN neuron bundle regulate the 24-hour cycle in your body. Changes in the CLOCK genes influence your chronotype status - average, or early, or late.

A study was carried out on hamsters to study the contributing factors to chronotype. Scientists replaced the SCN of early chronotype hamsters with that of average chronotype hamsters. To their surprise, the hamsters still went to sleep and woke up early, according to their early chronotype. 

This is because, other than the SCN clock, the body also contains other biological clocks, all of which contribute to a person’s chronotype. And, this is why it can be very difficult to break out of your natural sleeping pattern. 

Chronotype Genetic Test

To know what your chronotype is based on your genes, you can get a genetic test done. Most genetic tests provide your DNA information in the form of a text file called the raw DNA data. At Xcode Life, can help you interpret this data.

All you have to do is upload your raw data and order a sleep report. Xcode Life then analyzes your raw data in detail to provide you with a comprehensive sleep analysis, including information on your chronotype and risk for various sleep disorders.

Video

The Science Of Sleep

The common ingredient in your tea, coffee, and energy drinks, caffeine, is the strongest psychoactive drug in the world. It is not a secret that caffeine helps you stay awake. But, how does it manage to do that?

Let's first look at how your brain puts you to sleep.

Adenosine triphosphate, or ATP, is the energy currency of your body. ATP is broken down into a molecule called adenosine in the brain. Adenosine moves around the neurons keeping up your energy levels throughout the day.

As the day progresses, some of these adenosine molecules exit the neurons and bind to the receptors. This causes sleepiness. There are two adenosine receptors, A1 and A2A. A1 receptors are found on neurons that keep the brain awake, and A2A receptors are found on neurons that initiate sleep. 

When adenosine binds to the A1 receptor, it reduces the activity of the neurons. When it binds to the A2A receptors, it increases the activity of the receptor. The combination of this binding, along with a few other hormonal changes, makes you sleepy. When you sleep, the adenosine is slowly released from the receptors, and when there isn't enough left to bind to the receptors, you wake up from a refreshed night of sleep.

Caffeine and Sleep

Caffeine and adenosine are similar in structure. So, the caffeine can mimic the adenosine molecules and bind to the A1 and A2A receptors. However, caffeine's structure isn't identical to adenosine. As a result, it doesn't produce the "sleepy" effect.

Instead, it wards off sleepiness by preventing the adenosine molecules from binding and initiating the sleep process.  

But this effect lasts for only two to four hours, depending on how fast your body can break down the caffeine. This largely depends on your genes. When your body starts getting used to the caffeine intake, it produces more adenosine receptors to counteract the effect of caffeine. You may have to end up consuming more caffeine to stay awake!

Caffeine Withdrawal

Increased caffeine consumption leads to increased production of the receptor, which again results in increased caffeine consumption. It is a pretty vicious cycle that can make you a chronic caffeine drinker! As a result, you eventually develop caffeine tolerance. When you abruptly bid farewell to caffeine, you may end up feeling way too drowsy because of the additional adenosine receptors in the brain. This is called caffeine withdrawal.

Caffeine withdrawal is characterized by other symptoms like:

• Fatigue
• Drowsiness 
• Irritability
• Inability to concentrate. 

They can last up to a week till the number of receptors goes back to normal. Caffeine isn't as addicting or life-threatening compared to drugs like cocaine. People tend to have a mild physical dependence on this drug. People cannot overdose on caffeine easily. An average adult would have to have about 100 cups of coffee, which amounts to 10 grams of caffeine, to experience any lethal effects of caffeine.

The adenosine receptors are also found in the heart and kidneys. Activation of the receptors decreases the activity of these organs as well. Reduced urine output and heart rate prepare the body for a good night's sleep. However, when caffeine goes and binds instead, it results in increased heart rate and urine production. This is manifested as caffeine jitters and dehydration.

Caffeine isn't very dangerous; however, children should avoid it. Scientists haven't understood the effect of caffeine on a developing brain yet. It is also unhealthy for an adult to be consuming too much caffeine. Sleep and rest are essential for healthy brain function and well-being. 

Getting a Genetic Test

The genes that metabolize caffeine can say a lot about how much caffeine is "healthy" for you. A genetic test can help identify your caffeine metabolizing status. 

Xcode Life's Gene Sleep report profiles genes that influence sleep upon caffeine consumption. All you need is your genetic ancestry test raw data to get started!

Video

Introduction: What Is Snoring?

Snoring is the loud or harsh sound from the nose or mouth that occurs when breathing is partially obstructed. The sound is produced when the soft palate and other soft tissues (such as uvula, tonsils, nasal turbinates, and others) in the upper airway vibrate.

Affecting nearly 90 million Americans, it can lead to disturbed, unrefreshing sleep, ultimately resulting in poor daytime function. Snoring is caused due to obstruction of air passage, resulting in the vibration of respiratory structures and the production of sound during breathing while asleep.

Snoring is more prevalent in males than in females. Certain risk factors such as genetic predisposition, throat weakness, obesity, mispositioned jaw, obstructive sleep apnea, sleep deprivation, alcohol consumption, and mouth breathing are associated with snoring.

How Do Genes Influence Snoring Risk?

Twin and family studies have identified the association between genetic factors and snoring risk, with heritability ranging between 18 to 28%.

A recent study published in 2019 leveraged data from a large U.K. Biobank study consisting of the Australian adult population to identify the molecular mechanisms associated with snoring.

MSRB3 Gene and Snoring

MSRB3 is associated with protein and lipid metabolism pathways, which are related to hippocampal volume (a region in the brain) and lung function. Such genetic associations are consistent with the findings that severe bouts of snoring may be due to:
- Nocturnal oxygen desaturation (temporary drop in oxygen levels in hemoglobin)
- Lowered neuropsychological functions, with reduced ability to consolidate memory.

rs10878269 And Snoring

The rs10878269 is G>A polymorphism located in the MSRB3 gene. A study by Jones, Samuel E., et al.2016 showed that variant rs10878269 was significantly associated with reduced snoring risk.

Non-genetic Influences On Snoring

• Mouth anatomy* : A low, thick, and soft palate can narrow down the airway and may result in snoring
• Nasal problems : Deviated nasal septum and nasal congestion can contribute to snoring.
• Sex : Men are more likely to snore or have sleep apnea than women.
• Obesity : Fatty tissues in the neck of obese/overweight people can narrow the airways and cause snoring.
• Sleep Deprivation : Not getting enough sleep can lead to throat relaxation.

Effects Of Snoring

Snoring is not often considered a serious health concern except in some conditions. Snoring can usually be cured through simple home remedies. Light and infrequent snoring is completely normal. Snoring that is linked to obstructive sleep apnea (OSA) is, however, worrisome and needs to be treated.

Tips For A Snore-free Sleep

1. Reduce the consumption of alcohol and sedatives as this relaxes your muscles and leads to snoring.
2. Maintain your weight as obesity and being overweight are risk factors for snoring and sleep apnea.
3. Change your sleeping position. When you sleep on your back, your airway has higher chances of getting blocked. Sleeping on your side, raising your head by a few inches, or using a pillow to improve your neck position are a few alternative sleep positions to try.
4. Relieve nasal congestion before you sleep.
5. Anti-snoring mouthpieces can be used to hold your jaw and tongue in a suitable position to prevent blockage of the airway,
6. Throat exercises can help strengthen the muscles and prevent them from collapsing during sleep.
7. Try to quit smoking. Smoking can result in inflammation in the upper airway passage, and this blocks airflow.

Video

Summary

1. Snoring is a common sleep disorder that affects over 90 million Americans. It is characterized by a loud noise from the nose/mouth due to an obstructed airway.
2. Genetic predisposition, throat weakness, obesity, mispositioned jaw, obstructive sleep apnea, sleep deprivation, alcohol consumption, and mouth breathing are some risk factors associated with snoring.
3. The MSRB3 gene, associated with protein and lipid metabolism pathways related to lung function and hippocampal volume, affects sleep-related snoring. The rs10878269 SNP, a G>A polymorphism, is associated with a reduced risk of snoring.
4. Snoring is not a serious health concern unless linked to other sleep disorders like Obstructive Sleep Apnea(OSA).
5. Changing your sleeping position, maintaining a healthy weight, reduced alcohol consumption and smoking, and throat exercises are some of the recommendations to have a snore-free sleep at night.

References

https://pubmed.ncbi.nlm.nih.gov/32060260/

Abstract

Depression, a fairly common mood disorder, is a major influencer of health and wellness. Recent research has found a link between depression and sleep timing and preferences. The reports suggest that an individual who wakes up an hour earlier than usual has a significantly decreased depression risk. These results could help a person improve their mental health by fixing their sleep cycle.

The Link Between Sleep And Mood

Depression is characterized by feelings of loss, sadness, and anger. Such mood disorders are usually linked to lack of sleep and various other factors like stress, family history, etc. 

Previous studies have found an association between sleep timing and mood. Further insights from these studies have shown that night owls are twice as likely to suffer from depression as early risers regardless of their sleep duration. 

Another study showed that early risers were up to 27% less likely to develop depression over the years. But, additional research is needed to examine the genetic and environmental factors and understand the relationship between sleep and mood disorders.

12-24% of our sleep timing is influenced by genetics. Researchers have found over 340 genetic changes that play a role in a person’s chronotype - morning or evening person.

Mood disorders can disrupt sleep cycles; hence researchers have been working on finding a causal relationship between them. These findings could hold significant implications for improving  mental health.

Waking just one hour earlier cuts depression risk by 23%

A genetic study led by Iyas Daghlas M.D aimed to understand the protective nature of sleep schedule shifts. 

The study was conducted with data of up to 850,000 individuals from UK-based Biobank and DNA testing company 23andMe - 85,000 who had worn wearable sleep trackers for seven days and 250,000 who had filled out sleep-preference questionnaires.

A third of this group self-identified as morning larks, and only 9% were night owls; the rest were somewhere in the middle.

The study also used a different sample consisting of genetic information along with surveys about diagnoses of major depressive disorders and anonymized medical and prescription records.

The results of the study suggest that scheduling your sleep an hour early can reduce your risk of major depressive disorder by 23%. Further, going to bed 2 hours early can cut down the risk by 40%! 

The study also lays down a possible explanation that could explain this result. Going to bed early makes it easier to wake up early in the day. This could mean longer exposure to the daylight, which has a positive impact on mood. Others seem to suggest that having a biological clock that differs from most people can itself be depressing. 

Recommendations to become an early riser

• Practice going to bed early. Research suggests that an early bedtime improves academic performance and cognitive thinking.
• Start waking up a little earlier than you did the day before. Studies have linked early risers to  increased physical activity and improved attention.
• Motivate yourself to wake up early with a planned schedule. Studies have reported an association between the motivational state of mind and the sleep cycle of an individual.
• Reward yourself when you wake up early. Studies have linked the reward system to learning behavior and improved wellness. 

Summary

• Depression, a mood disorder characterized by feelings of sadness, is usually linked to lack of sleep and other factors like family history, stress, etc.
• Previous studies indicate a link between sleep timing and mood. Further research on this revealed that night owls are more likely to suffer from depression than early birds.
• A genetic study was conducted on 850,000 individuals to understand the causal relationship between sleep schedule and depressive disorders.
• Researchers identified around 340 common genetic variants which influence an individual’s sleep preference and time.
• Findings of the study suggest that waking up an hour earlier reduces your risk of depression by 23%.

References

• https://www.sciencedaily.com/releases/2021/05/210528114107.htm
• https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2780428
• https://www.healthline.com/health/depression
• https://www.webmd.com/depression/sleep-depression
• https://healthysleep.med.harvard.edu/need-sleep/whats-in-it-for-you/mood
• https://jackheimbigner.medium.com/how-to-become-an-early-riser-in-5-simple-steps-41c3904e5b1f
• https://jackheimbigner.medium.com/how-to-become-an-early-riser-in-5-simple-steps-41c3904e5b1f

What makes a person an early riser or a night owl?

Chronotype is influenced by differences in circadian rhythm, which refers to the fundamental 24-hour physiological cycle essential for various molecular and behavioral processes. It helps regulate sleep patterns.

The timing of circadian rhythms varies across individuals and is influenced by both environmental and genetic factors. People with earlier rhythms tend to rise early in the morning and feel sleepy earlier in the night. If your body sides with the “morning clock” then you are a “morning person.” The other end of this spectrum has people with delayed rhythms. They tend to sleep and wake up late and are often referred to as an “evening person” or a “night owl.”

Research has shown that morning people are more focused, persistent, agreeable, plan their future better, and are less likely to smoke and drink or get depressed. They may exhibit characteristics like:
- Waking up early
- Being more active during the morning hours
- Being more focused and happy
- Being more productive during the day

Similarly, night owls enjoy a burst of strength during the night and may exhibit characteristics like:
- Waking up late
- Being more active during the evening hours
- Being more creative and adventurous
- Being more productive during the night

How Does Genetics Influence Circadian Rhythm?

A GWAS study of self-reported chronotype (morning/evening person) of UK Biobank data identified 22 regions in the circadian rhythm and photo-reception genes associated with morningness. This was also replicated in a 23andMe study.

One of the strongest associations was seen in the rs516134 SNP located near the RGS16 gene.

RGS16 Gene and Circadian Rhythm

The RGS16 gene encodes a protein that belongs to the regulator of G protein signaling. This protein is responsible for turning off certain signal communications between cells in the body.

Microarray studies and gene expression analysis have demonstrated that the RGS16 gene exhibits circadian variations. According to a study, mice lacking this gene have a longer circadian period.

rs516134 SNP and Morningness

The rs516134 is a C>T polymorphism located in the RGS16 gene. The C allele is found to be strongly associated with morningness.

Non-genetic Influences On Circadian Rhythm

A study found that morningness is significantly associated with gender, with a prevalence of 39.7% in males and 48.4% in females.

Also, people over 60 were more likely to prefer mornings than people under 30 - meaning people’s sleep preferences may change over time.

Effects of Circadian Rhythms

Circadian rhythms affect day-to-day bodily functions such as sleep, eating habits, hormones release, and body temperature.
Many studies have documented that irregular rhythms are linked to various chronic conditions such as sleep disorders, obesity, depression, diabetes, hypertension, bipolar, and schizophrenia.
It is known that the vast majority of patients with depression have sleep abnormalities; either they sleep too much or have insomnia and can’t sleep at all.
Several genetic variants are correlated with how circadian rhythms function and their association with health conditions.
The interplay between genetics and non-genetic factors (such as sunlight, eating habits) with circadian rhythm is clear.
Maintaining a routine with a balanced lifestyle may help to stabilize the internal biological clock and health.

Tips To Become An Early Riser

1. Sleep early and shift your bedtime gradually to get about 7-9 hours of sleep.
2. Stay consistent with your timings. Set your alarm clock to the same time every morning to make it easier to get into a routine.
3. Move your alarm clock to a distance where you would have to get up to turn it off. There are a few apps like Smart Alarm or Math Alarm which require you to do an activity to turn off the alarm. This will help you stay awake and not snooze your alarm and go back to sleep.
4. Exposure to bright light in the morning, especially natural light, helps make you alert and gets you used to wake up early. Your body’s circadian rhythm is responsive to light and dark conditions.
5. Get active in the morning and go for a jog or run. You can even hit the gym in the morning and finish your workout. This will give you the energy to start your day.
6. Think about the various reasons why waking up in the morning could be beneficial and how you can be more productive during the day.
7. Use something to look forward to in the morning as bait to wake up for. A cup of hot coffee, a nice breakfast, a puzzle in the newspaper are a few of the things that you could look forward to.
8. A protein-heavy meal is said to increase your dopamine levels, facilitating wakefulness, and making you ready for the day.

Summary

1. Circadian rhythm, which refers to the fundamental 24-hour physiological cycle essential for various molecular and behavioral processes, helps regulate your sleep patterns.
2. People with earlier rhythms are termed as morning people, whereas those with delayed rhythms are termed as night owls. Morning people are known to be more focused and happy, while night owls are known to be more creative and adventurous.
3. Both environmental and genetic factors influence your sleep patterns.
4. Several genes are known to affect circadian rhythm. The C allele of the rs516134 SNP in the RGS16 gene, which is involved in turning off certain signals between cells in the body, is known to be strongly associated with morningness.
5. Circadian rhythms affect your day-to-day functions, and irregularity is associated with chronic health conditions.
6. Following a routine with a balanced and healthy lifestyle can help set your biological clock right.

References:

https://pubmed.ncbi.nlm.nih.gov/27494321/
https://pubmed.ncbi.nlm.nih.gov/26835600/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5428740/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4018537/

Introduction

Sleep is a critical component of optimal health. A healthy sleep comprises various aspects, including adequate duration, good quality, and the absence of sleep disorders. Inadequate sleep at night is generally associated with:
- Daytime sleepiness
- Daytime fatigue
- Depressed mood
- Poor functioning
- Other health issues

Sleep duration refers to the total amount of sleep obtained either during the nighttime sleep event or across the 24-hr period.

Importance of An Adequate Sleep

Getting enough sleep at night is very important for several reasons. Sleep is linked to your mental and physical health and quality of life. When you get adequate sleep at night, you can be more productive and concentrate better during the day. It reduces your risk of heart disease and prevents depression. Your immune system becomes stronger as sleep helps the body to repair and recover. Your athletic performance can also be improved because of a good night’s sleep. Not getting enough sleep can make you gain weight faster.

RDA: What Is The “Ideal” Sleep Duration?

National Sleep Foundation guidelines recommend 7-9 hours of sleep per night for healthy adults. Babies, young children, and teens need even more sleep to enable their growth and development. People over 65 should also get 7 to 8 hours of sleep per night.

How Does Genetics Affect Sleep Duration?

Studies have shown that certain genetic variants influence habitual sleep duration, which explains why some individuals need more sleep than others.
Twin studies have shown that the heritability estimation of sleep duration is around 10 - 40%.

A GWAS study of self-reported chronotype and sleep duration of UK Biobank data identified several genetic regions associated with sleep duration. This study documented that people with genetic variants for longer sleep duration reported an average of 22 minutes more sleep.

PAX8 Gene and Sleep Duration

The PAX8 gene encodes a member of the paired box (PAX) family of transcription factors involved in thyroid follicular cell development and the expression of thyroid-specific genes.

Variations in the PAX8 gene may affect different functions, including DNA binding, gene activation, and protein stability.

Research studies have found that the sleep-wake cycle may be influenced by regulating thyroid hormone levels. Individuals with hypothyroidism (a condition in which the thyroid gland does not produce enough thyroid hormones) are prone to excessive sleepiness. People with hyperthyroidism (in which the thyroid makes too much of the hormone), on the other hand, may have insomnia.

rs62158211 And Sleep Duration

The rs62158211 is a G>T polymorphism located in the PAX8 gene. The T allele is associated with longer sleep duration.
A study documented that the rs62158211 was associated with an average 2.6-minute per-allele change in sleep duration.

Non-genetic Influences On Sleep Duration

Some risk factors that lead to shorter sleep duration include alcohol consumption, smoking, and physical inactivity.

Effects of Sleep Duration on Health

Few epidemiological and genetic studies have demonstrated a strong biological link between abnormal sleep duration, risk of schizophrenia, type 2 diabetes, fetal growth, and Crohn's disease.

Sleep duration is also associated with cardiovascular diseases, type 2 diabetes, depression, automobile and workplace accidents, learning and memory problems, and prospective mortality.

TipsTo Become An Early Riser

1. Sleep early and shift your bedtime gradually to get about 7-9 hours of sleep.
2. Stay consistent with your timings. Set your alarm clock to the same time every morning to make it easier to get into a routine.
3. Move your alarm clock to a distance where you would have to get up to turn it off. There are a few apps like Smart Alarm or Math Alarm which require you to do an activity to turn off the alarm. This will help you stay awake and not snooze your alarm and go back to sleep.
4. Exposure to bright light in the morning, especially natural light, helps make you alert and gets you used to waking up early. Your body’s circadian rhythm is responsive to light and dark conditions.
5. Get active in the morning and go for a jog or run. You can even hit the gym in the morning and finish your workout. This will give you the energy to start your day.
6. Think about the various reasons why waking up in the morning could be beneficial and how you can be more productive during the day.
7. Use something to look forward to in the morning as bait to wake up for. A cup of hot coffee, a nice breakfast, a puzzle in the newspaper are a few of the things that you could look forward to.
8. A protein-heavy meal is said to increase your dopamine levels, facilitating wakefulness, and making you ready for the day.

Summary

1. Sleep duration refers to the total amount of sleep obtained during the nighttime sleep event or across the 24-hr period. Getting enough sleep at night is necessary for both mental and physical well-being.
2. For healthy adults, 7-9 hours of sleep is recommended. Babies, children, and teens tend to sleep for much longer.
3. Genetics is found to influence sleep duration. The PAX8 gene, which plays a role in thyroid development, is associated with the sleep cycle. The regulation of thyroid hormone levels affects the sleep-wake cycle. The T allele of the rs62158211 SNP in this gene is associated with longer sleep duration.
4. Certain risk factors like smoking, alcohol consumption, and physical inactivity lead to decreased sleep duration.
5. Abnormal sleep duration is linked with the risk of schizophrenia, type 2 diabetes, fetal growth, and Crohn's disease.
6. Exercising during the day, following a proper sleep routine, reducing alcohol consumption and smoking, a comfortable environment, and less frequent napping are some of the things that can make your sleep duration normal.

References:

https://www.sleepfoundation.org/articles/how-much-sleep-do-we-really-need
https://pubmed.ncbi.nlm.nih.gov/27992416/
https://pubmed.ncbi.nlm.nih.gov/27494321/
https://pubmed.ncbi.nlm.nih.gov/25469926/