There is a Western rumor that people will feel elated and sleepy after a Thanksgiving turkey dinner. This is due to the high content of tryptophan in turkey-because tryptophan has a relaxing function.
Tryptophan is considered to be a substance that can help sleep, and many rumors say that milk contains tryptophan, and drinking a little before going to bed is helpful for sleep.
So, are these statements reliable?
Effect of Tryptophan on Sleep
1. Tryptophan has a positive effect on sleep, but it has a negative effect on other sleep stages.
Previous studies have found that tryptophan does have a positive effect on this stage of [falling asleep] and can help to enter the sleep state.
However, in other sleep stages, such as deep sleep at night, tryptophan may play the opposite role, especially when tryptophan is ingested in the form of supplements.
2. Tryptophan is sufficient before it can take effect.
Moreover, the effect of tryptophan on [falling asleep] is only possible if sufficient amount is ingested.
If you take turkey as an example, if you really want to take in the amount of tryptophan that can take effect, it means that you have to eat 36 kg of turkey meat at one time! Do you think you can still sleep after eating so much meat?
3. The action of tryptophan is affected by other components
In addition to the amount, tryptophan needs to cross the blood-brain barrier to play a role and affect sleep.
- When you eat foods rich in protein, including milk, the presence of other amino acids weakens the ability of tryptophan to cross the blood-brain barrier and limits its function. When you eat foods high in carbohydrate, the release of insulin will help tryptophan enter the blood circulation of the brain more easily.
To sum up, it is not realistic to obtain tryptophan from bedtime food to help sleep.
Milk helps sleep? Mainly [placebo effect]
Therefore, it seems that it is not because milk contains tryptophan enzyme that hot milk can help sleep. After all, the amount of tryptophan in a cup of milk is very, very limited.
So is it what who made us absolutely sure that a glass of hot milk can help us sleep? Perhaps, this is just a kind of habit power.
Just like a bedside toy and your mother tapping your body gently, a cup of hot milk has long been associated with sleep.
We call this [placebo effect]: this psychological connection makes you have the idea of sleeping immediately after drinking a glass of milk.
Is there any other substance in milk that can promote sleep? Uh… Maybe.
What is an ideal bedtime food?
There is no definite answer as to whether eating certain foods before going to bed can really help you fall asleep.
But what is certain is that eating too much food before going to bed will affect digestion, lead to sleeplessness, excess energy and easy gain weight.
General advice: Avoid eating 2 ~ 3 hours before going to bed.
Dinner and supper should not be too late or too early. If you eat dinner early, feel a little hungry before going to bed, or need to work and study late at night, you can eat a little food.
The ideal night food should be carbohydrate-based and contain a certain amount of protein (tryptophan is best, of course).
For example, a small piece of bread, a few small biscuits or a small banana and other fruits, a small amount of half a cup of milk, a small cup of yogurt or a cup of soya-bean milk are fine.
In this way, the brain will not suffer from hypoglycemia, the intestines and stomach will be soothed, and the brain may produce a certain amount of serotonin hormone, which is called [sedative hormone], and may also help sleep.
Calm your stomach, don’t eat too much, don’t be hungry, and have a good sleep.