"Health from eating" series | What can you eat to help you sleep well? Recommended sleep-promoting foods

It is said that "Spring sleep makes you sleep without knowing the dawn", so spring should be a season for sound sleep.

However, in modern society, even in spring, there are still countless people who suffer from insomnia, tossing and turning, and even "counting sheep" with their eyes open until dawn. Many people who are prone to insomnia ask: Is diet related to sleep? If you want to improve your sleep quality, what should you consider when arranging your diet?

In addition to some traditional health-preserving ingredients that can be used as both medicine and food, such as sour jujube seeds, longan, lotus seeds, etc., the nutrients in food may also have an impact on sleep.

1. Fat intake and sleep

When you eat more fat, you may get less sleep overall.

People who consume the most fat are more likely to sleep less than 7 hours a day. People who consume less fat are more likely to sleep 7-9 hours. Foreign researchers have also found similar situations among middle-aged and elderly people. People who consume more fat and cholesterol have shorter sleep time. Obese people tend to sleep shorter, which may also be related to their love of high-fat foods.

In addition, the timing of fat intake may also be important. Eating a high-fat meal before going to sleep at night seems to have a greater impact on sleep quality, prolonging the time it takes to fall asleep, reducing the time spent in REM sleep, and increasing the time spent awakening during the night.

2. Protein intake and sleep

Under the premise of a high GI diet, increased protein intake will shorten the duration of sleep, increase wakefulness before sleep and after waking up, and make it less likely to fall asleep. This may suggest that consuming protein in the morning is conducive to wakefulness, while consuming protein at night may cause a good spirit before bedtime and not want to fall asleep.

Tryptophan is an amino acid associated with sleep because it can be converted into serotonin in animals, a neurotransmitter that makes people feel calm. At the same time, tryptophan is also one of the raw materials for synthesizing melatonin.

However, if you eat a lot of protein food for dinner, it tends to increase the amount of larger neutral amino acids such as leucine, isoleucine, and valine, while the proportion of tryptophan tends to decrease, and the amount entering the brain barrier is reduced, which may reduce the synthesis efficiency of serotonin and melatonin.

Therefore, consuming foods rich in tryptophan at night may be a good way to sleep. Supplementing whey protein with extra tryptophan for dinner can make the brain more alert and less sleepy when waking up in the morning. If the proportion of carbohydrates in dinner is increased, the ratio of tryptophan to other hydrophobic neutral amino acids in the blood can also be increased, which is likely to be beneficial to sleep; on the contrary, if a large amount of high-protein foods such as meat are eaten, the proportion of tryptophan in the blood will decrease, making people not want to fall asleep.

3. Micronutrients and sleep

Vitamin B6 is important for sleep. This vitamin helps convert tryptophan into serotonin. In fact, one of the symptoms of vitamin B6 deficiency is insomnia.

Vitamin B12 is involved in the proper functioning of the circadian rhythm, which affects melatonin levels. Studies have shown that taking vitamin B12 in the morning can increase wakefulness. Folic acid and vitamin B12 have a synergistic relationship, and both are vitamins required for central nervous system regulation. Folic acid deficiency increases the risk of insomnia and restless legs syndrome, so when treating insomnia, doctors may recommend taking folic acid and vitamin B12 at the same time.

In addition, vitamin C, vitamin E, and vitamin D deficiency are all associated with poor sleep. When vitamin D is insufficient, the synthesis of serotonin will be disrupted, the sleep time at night will be shortened, and it will be easier to feel drowsy during the day.

Among minerals, calcium, magnesium and zinc may help. In particular, calcium and magnesium deficiency can make people more prone to anxiety and tension, so supplementing them can help improve sleep quality.

4. Food and sleep

Foods that have been found to be beneficial in improving sleep include sour cherries, kiwis, bananas, milk, etc.

Some of these foods contain melatonin, while others are rich in serotonin or tryptophan. For example, sour cherries are rich in melatonin, while bananas contain more serotonin.

The serotonin content in bananas is related to ripeness. As the bananas ripen naturally, the melatonin content increases, but once they are overripe, the content decreases.

In fact, many fruits are rich in a variety of biogenic amines. For example, kiwi fruit is rich in folic acid, contains more 5-hydroxytryptamine, and also contains more vitamin C, so it also has a sleep-inducing effect. Other fruits such as grapes, pineapples, and red plums are also sources of 5-hydroxytryptamine.

Milk contains serotonin and melatonin, and is also rich in tryptophan. Interestingly, when cows are milked in the dark at night, the melatonin content in their milk is higher than when they are milked during the day.

To sum up, the relationship between nutrients and sleep is roughly like this:

1. Excessive fat intake is not conducive to falling asleep, especially at night it is best to eat less greasy food.

2. More protein intake will make people more awake, sleep less at night, but not easy to sleep during the day. So you can consume more protein in the morning and at noon, and less at night.

3. Eating more carbohydrates will make people sleep longer, especially eating high GI carbohydrate foods at night will make people fall asleep faster. However, eating too many high GI carbohydrates during the day also has the risk of making people feel drowsy. So you can eat less carbohydrates at noon and eat more at night.

4. Vitamin B6, vitamin B12, folic acid, vitamin D, vitamin C and vitamin E all seem to help prevent insomnia. However, supplementing them when you are deficient does not mean that the more you eat, the better. Fruits and vegetables and whole grains and beans are helpful for taking in enough B vitamins, and exposure to sunlight can provide vitamin D.

5. Calcium and magnesium help relieve anxiety and tension, so supplementing them can help improve sleep quality. Eating more green leafy vegetables, tofu and dairy products can help you get enough calcium and magnesium.

Foods such as millet and milk, because of the higher proportion of tryptophan in their protein, are more beneficial to improving amino acid balance and promoting sleep than foods such as meat.

Here is a drink that may have a sleep-inducing effect: hot milk with maltose.

It is very simple to make: wrap the maltose (in stick or block form) sold in the supermarket with a clean cloth or kitchen paper and crush it. Then add a spoonful to hot milk and stir well. People who are lactose intolerant can use lactose-free milk.

The maltose in it can be quickly broken down into glucose, which is beneficial to the synthesis of melatonin and also helps increase the proportion of tryptophan in the blood; while milk can provide tryptophan, vitamin B6, vitamin B12 and calcium.

People who are not allergic to milk and do not have blood sugar problems can give it a try. Drink a glass of milk 1-2 hours before going to bed, soak your feet, stretch your tired shoulders, neck, arms, and back muscles, and then lie down comfortably to sleep.

If you don’t want to drink milk, you have the following options:

1 small bowl of traditional millet porridge with lily and lotus seeds, preferably with a vitamin B6 tablet. Or 1 small banana, or 2 kiwis.

(The author Fan Zhihong is a registered nutritionist and professor at the School of Food Science and Engineering, China Agricultural University)

Source: People's Daily Online