When talking about health, sleep is often overlooked and less mentioned than diet and exercise. However, humans spend ⅓ of their time sleeping and from this, we know how important sleep is for us.
How much sleep do we need?
When we grow older, the fewer hours we sleep. A newborn baby can sleep up to 17 hours per day, a school-age child needs 9 to 11 hours of sleep.
Meanwhile, for an adult, we need at least 7 to 9 hours of sleep per day.
However, people nowadays rarely got enough sleep, as we have too much of things to do - endless work, and countless stimulations that we have to sacrifice our sleep time.
You might think that you can sleep for just 6 hours (or even less) and still function well. However, many studies have shown that chronic sleep deprivation can lead to terrible health consequences.
Don’t believe it? Continue reading.
Impact of Sleep Deprivation on your health
Sleep deprivation is a more severe problem than you imagine.
Let’s start with short-term side effects:
Not enough sleep makes your response slower. You will find it hard to focus, think and make decisions - this affects your efficiency and your performance.
Besides, when you don’t have enough sleep, you will become more irritable. It is difficult to feel excited when you are in sleepy mode. ( Imagine going to Disneyland after 2 sleepless nights?)
More seriously, sleep deprivation can be fatal. Driver sleepiness is one of the major factors that cause road accidents, especially long-hour drives.
What happens to your body if you are constantly sleep-deprived?
OBESITY
Sleep deprivation is associated with weight gain. A study consisting of approximately 2600 workers in Brazil, showed that worker who sleep less than 5 hours, has a higher prevalence of obesity. (1)
This might be due to the relationship between sleep and hormone modulation. When you have insufficient sleep time, your body will secrets more ghrelin and reduce the level of leptin. Ghrelin is a “hunger hormone”, which stimulates your brain that “you are hungry” and seek out food. On the other hand, leptin is appetite suppression and signals your brain to stop eating. (2)
Thus, a significant increase in the level of ghrelin and reducing the level of leptin will result in more food intake. In long term, excessive calorie intake can lead to weight gain and even obesity.
WEAKEN IMMUNE SYSTEM
There is a wisdom saying that “when you are sick, sleep more can fasten the healing”.
Sleep and the circadian rhythm (The natural cycle of physical, mental, and behavioural changes that our body goes through in a 24-hour cycle) bring a strong influence on our immune system.
Getting an adequate amount of quality sleep helps to strengthen our innate and adaptive immunity, more responsive to vaccination and less severe allergic reactions. (3)
HYPERTENSION & CARDIOVASCULAR EVENTS
Are you always sleep less than 5 hours per day? If yes, then you have to be aware. Sleeping less than 5 hours is associated with a 45% increase in risk of cardiovascular event. (4)
It is thought sleep is a process of healing. When we sleep, our heart rate goes down, blood pressure drops, and stress released. Under short period of sleep, the body doesn’t have enough time to go through the process, causing the stress hormone swings and blood pressure goes up.
How to have quality sleep?
1. Avoid caffeine after 2 pm
Many of us consume caffeine in order to stay alert. However, it might cause insomnia in some people. Each individual responds to caffeine differently, and it depends on many factors like the amount and frequency of caffeine consumption, sex, weight, personal sensitivity towards caffeine and so on.
Research has stated that caffeine elimination time range from 1.5 to 9.5 hours.(5) So, avoid consuming caffeine after 2 pm. If you are having problems with sleep or are sensitive to caffeine, try not to consume it.
If you really crave coffee in the late afternoon, choose a decaf alternative.
Except coffee, tea, chocolate, and energy drinks do contain caffeine, just a matter of quantity.
2. Have a consistent sleep schedule
Fixing your bedtime helps to get quality sleep.(6) An irregular sleep time will disturb our circadian system, which is important in regulating heart rate, blood pressure and other cardiovascular function.
We are being told that we must “go to the bed earlier and wake up early in the morning”, but it is not always the case. Don’t force yourself to go to bed as early as 8 pm if you find it difficult to adapt. Find a sleep time which is most suitable for you, where you can fall asleep easily, wake up and feel energized.
Regardless of sleeping time, getting adequate hours of quality rest is still the priority for all.
3. Expose to sunlight
Sleep duration is largely affected by circadian rhythm, and circadian rhythm is affected by the level of melatonin. Melatonin is a hormone that is controlled by light exposure, it increases during dark times and reduces when expose to light.(7)
When expose to natural light, our circadian rhythm synchronizes with sunrise and sunset, making us stay awake in the daytime and sleep during the nighttime.
Go outside and expose yourself to sunlight for 30 minutes, which not only helps in better sleep but improves your mood too.
4. Avoid blue light before sleep
Contrary to daytime, we need to reduce the exposure to light during nighttime. However, the massive use of electronic devices makes it hard to accomplish. Exposure to blue light (emitted from 3C devices like phone, computer and TV) affect sleep by suppressing the production of melatonin, thus causing arousal.(8)
Besides, when using electronic devices, our brains keep stimulated by information and image, making it harder to fall asleep.
Reducing the usage of electronic is one of the best ways to improve sleep quality. Try to make your bedroom a “device-free zone” during bedtime. Turn off the wifi, set it to silent mode and left it as far from your bed as you can.
Try other things before sleep, like reading and listening to music instead of playing with the phone.
Just as you need to rest, so does your phone. Stop torturing your phone, let it rest.
5. Avoid eating large meals before sleep
We usually have our largest meal during dinner. However, if your dinner is very late, you might need to change this habit.
Heavy meals close to sleep time have a negative impact on sleep quality.(9), (10)
After we eat, our body needs energy to digest food. The heavier the meal, the longer time our body needs to process the food. When we sleep, the digestion process slows down and causes discomfort.
Besides, overeating before sleep in long term may induce acid reflux, which is a condition where you feel a backwash of sour liquid and a burning sensation in your chest.
To prevent this, allow at least 3 hours of digestion period before you go to bed.
Consuming lighter meals and minimising high-fat food can also improve the condition.
6. Avoid drinking too much water before sleep
Besides food, it is recommended to limit water drinking before bedtime. Our body will automatically slow urine production when we sleep. However, drinking too much water before sleep might still cause an unwanted trip to the bathroom in the middle of sleep.
Nocturia is a symptom that you wake up more than once during the night to urinate. This is more common among the elderly. Nocturia can disrupt our sleep cycle, and as a result, linked to feeling tired during daytime, reduced productivity and getting irritated easily.
It is undeniable water is very important to our general health, but try to drink more during day time.
Going to the washroom before sleep is also a way to prevent nighttime washroom trips
7. Avoid alcohol before bedtime
Some people claimed that drinking alcohol helps them fall asleep easier, and it is true. Alcohol has a sedative effect that makes people feel relaxed and sleepy, but sleep quality is not guaranteed with alcohol.
Alcohol is linked to disturbed and fragmented sleep after its sedating effect disappeared.(11) Do you have an experience where - Even though you are able to sleep after consuming alcohol, you feel that you become even tired and did not rest well when you wake up next day in the morning.
Besides, chronic alcohol consumption leads to many other sleep issues like insomnia.(12)
Do not rely on alcohol to fall asleep. It's not your sleeping companion.
8. Exercise regularly
Exercise helps in improving sleep quality.
Exercise induces our body to produce endorphins, called the “happy hormone”. Endorphins reduce the perception of stress and pain, thus helping to promote better sleep. Constant training promotes a deeper and longer duration of sleep compared to people who do not exercise.(13)
Besides, exercise training also alleviates some sleeping disorders, like obstructive sleep apnea.
However, doing high-intensity exercise before sleep is not advisable. This is because sport increases hormones like adrenaline and epinephrine and increases alertness, which causes the opposite effect.
Prioritize exercise by putting it into your schedule. Do not hit the gym at 12 am only when you suddenly remember you haven’t exercised yet.
9. Optimize bedroom environment
Many bedroom factors determine if you can get a good sleep at night. These include bedroom temperature, brightness, noise, mattress and so on.
Many pieces of research proved that increased temperature reduces sleep efficiency.(14), (15), (16) The optimum temperature for sleep is approximately 19–21°C.
A dark bedroom is ideal for sleeping compared to a bright room. This is due to melatonin production in darkness, which promotes sleepiness.
Mattress matters when come to sleep. It is no need to invest in the most expensive mattress, but if your bed is sagging and you always wake up with back pain, it’s time to buy a new bed. Mattress with weak support not only causes uncomfortable sleep but affects your posture and back.
Recently, many essential oil merchants claimed their products contribute to better sleep. There are also studies showing the effectiveness of aromatherapy towards sleeping disorders.(17), (18)If you find it hard to sleep, might as well give it a try.
Design your bedroom in the best way for you to sleep.
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