Sleep well !
HK BioTek Intern
Have you ever had the experience of poor sleep? I am sure everyone of you did. The problem of insomnia is quite common in Hong Kong, on average 7 out of 10 Hong Kong citizens could not sleep well everyday which affects their daily lives to a certain extent.
There are numerous factors contributing to the quality of sleep, including work or academic performance, relationship and health problems like chronic pain. Because of these, some might have accumulated stress, anxiety or even depression and have to take medication. Also, poor lifestyle habits such as smoking, alcoholism and overconsumption of caffeine greatly affects one’s sleeping pattern. Some may use methods such as counting sheep, using phones or computers until feeling sleepy or drinking milk or alcohol to try to alleviate this problem. In more severe cases, they would even take sleeping pills and find doctors for help. Dietary factors play an important role in our abilities to sleep and here focuses on how to improve our sleep quality with nutrition.
Each of us has a biological clock in our inner brain, i.e. the circadian rhythm, this 24-hour cycle signaling us about the time to wake and sleep. Melatonin is a hormone secreted by the pineal gland (middle of the brain) at night and associated with sleepiness. Together with serotonin and dopamine, the physiological function is to convey the message of light and darkness to our brain and body and create a stable sleep-wake cycle. Melatonin is synthesized by tryptophan which is an essential amino acid that cannot be synthesized by the human body. Vitamins and minerals that act as the cofactors in the synthesis of melatonin, together with food rich in tryptophan and melatonin, might regulate the level of melatonin. In the conversion of tryptophan to serotonin then to melatonin, vitamins B6 & B12, folate, zinc and magnesium act as cofactors while polyunsaturated fatty acid (PUFA) activates the synthesis of melatonin. A higher intake of the above nutrients increases the release of both serotonin and melatonin, therefore prevents the occurrence of sleeplessness. In contrast, caffeine, ethanol as well as excess intake of sodium and glucose upset the biological clock by modifying its genes.
Foods and drinks suitable before going to bed
Grain and wheat products such as oats and cereals have low Glycemic Index (GI) with a large amount of tryptophan and vitamin B complex. Oats also contain natural melatonin.
Nuts and seeds such as walnuts, almonds and sesame are high in minerals like calcium and magnesium.
Vegetables rich in tryptophan include leafy green vegetables, soybeans, broccoli and mushrooms etc.
Fruits rich in tryptophan include banana, kiwi and cherries etc. Banana is especially rich in vitamin B6 and magnesium.
Honey contains various vitamins and minerals like magnesium and potassium. It is a kind of natural sugar that has a low GI and helps to relieve nervous tension and muscle fatigue.
Milk contains a huge amount of calcium and tryptophan, drinking a cup of warm milk helps to relax yourself before bed.
Fatty fish such as salmon and sardine have large pools of PUFA and vitamin B6, fostering the production of melatonin.
Foods and drinks should be avoided before bedtime
Although alcohol possesses a sedative property that we might fall asleep easily and quickly, people who drink before going to bed would experience a light sleep but not a sound sleep. This is due to the fact that enzymes in the liver start to metabolize alcohol and might keep them awake.
Caffeine from coffee or strong tea is something that keeps you awake, and possesses a diuretic effect.
Intake of spicy food promotes metabolism and raises body temperature leading to poorer sleep quality.
Other than a balanced diet, a healthy lifestyle should be adopted in order to improve your sleep quality. Moderate to vigorous aerobic exercise could lower the time you take to fall asleep and the amount of time getting awake at night i.e. to have a deep sleep. Physical activity thus helps to establish a better sleep quality and boosts the immunity which decreases the risk of having diseases. Some might even cut down their needs for sleep medication after doing regular exercise. What's more, exposing to sunlight in the daytime triggers the release of serotonin, which allows you to have a deep restorative sleep at night. The time for work and rest should also be set in regular intervals so that the body could get familiar with it and maximize the productivity and sleep quality.
Healthy lifestyle is absolutely necessary for a favorable sleep, by removing all the bad habits affecting your health, doing regular exercise and most importantly, having a balanced diet. If you are experiencing insomnia, or even being so stressed and mentally tensioned because of poor sleep quality, you should try to adjust your daily habits and adopt a healthy lifestyle. Hope you have a good night’s sleep!