The title of the article says ” Eating kiwi before bed can help you sleep better “. But, haven’t medical experts been saying that eating close to bedtime can cause a spike in blood sugar, thus disrupting sleep?
In most cases, that is accurate. Let alone eat junk foods or have a cup of coffee, even fruits and vegetables may cost you a good night’s sleep if consumed before bed.
However, it is not always the case. There are some fruits that are known to have a sleep-promoting effect. And, sweet and tart kiwifruit is one of them, arguably the most effective one.
Findings of a study revealed that “Eating 1 or 2 kiwis at night can increase sleep quality as well as quantity.“.
Besides, there are medical experts and nutrition specialists who consider kiwis as a potential natural remedy for insomnia.
In this article, we are going to provide all the available scientific evidence that could explain why kiwi is good for sleep.
To do that we will analyse the findings of a study performed by the researchers from Taiwan’s Taipei Medical University. Additionally, we will be quoting the expert opinions on the relationship between kiwi consumption and sleep.
Sleep Disorders are Common
However, the reality is getting 7 hours of uninterrupted sleep is a sort of privilege in this modern world. This is because, due to external and internal distractions (such as stress, temperature, noise/light pollution) many people around the world suffer from various sleep disorders (5),(6),(7).
Alone in the U.S.A, it was reported that sleep problems affect 50 to 70 million Americans regardless of their ages and life standards (8).
Kiwi Consumption and Better Sleep
As we discussed in the previous section, sleep disorders are quite common around the world. As such, many people look for ways to overcome their sleep problems.
If you are one of those, who often experience sleep problems, you should know; eating kiwis may not create a miracle and extinguish all of your sleep problems at once. However, eating kiwi before bed can help you better cope with sleep problems thanks to the sleep-promoting nutrients available in kiwis.
Considering that kiwi fruit is cheaper compared to drugs and has no side effects, eating kiwis before bed can be natural and budget-friendly way to overcome sleep problems. Plus, since kiwifruit is loaded with various crucial nutrients, they can contribute to your health in many ways.
Registered dietitian Lauren Manaker (who talked to eatthis.com) said; “I have found that one evening ritual that people are happy to stick to is to eat two kiwi fruits before they hit the hay. And, the evidence is clear—it can really work.” (9),(10).
Nutrients in Kiwis That Can Improve Your Sleep
As mentioned above, kiwifruit contains various essential nutrients. But the question is which of these nutrients found in kiwis are good for sleep?
Three nutrients are the main reason why kiwifruit is linked to better sleep. These nutrients are;
- Tryptophan (serotonin)
- Vitamin C
Now we know that since kiwis contain the above-given nutrients, they can potentially improve your sleep.
Again, there are some questions to ask, for instance;
- How do we know these nutrients aid sleep?
- Are there studies that can tell us these nutrients are good for sleep?
- In what quantity these nutrients are available in Kiwis?
These all are relevant questions. So, let’s examine these nutrients one by one and explain how they can aid sleep.
1-) Tryptophan in Kiwis Can Aid Sleep
The term ” Tryptophan ” may sound quite unfamiliar. Basically, it is an amino acid.
Since the human body can’t produce tryptophan, it has to be obtained from foods (13).
So, how does tryptophan promote sleep?
To begin with, it is important to underline the fact that tryptophan doesn’t directly make you sleepy. It, rather, plays a crucial role in the production of certain hormones that regulate the sleep-wake cycle.
Essentially, the role of serotonin (aka happy chemical) in sleep isn’t fully understood even by scientists.
Unlike serotonin, melatonin has a certain role in promoting sleep.
It bears repeating, the human body needs serotonin to produce melatonin and needs tryptophan to produce serotonin. That is to say tryptophan > serotonin > melatonin. Bear in mind tryptophan has to be taken from the foods.
This is why tryptophan-containing foods are heavily associated with sleep.
The conclusion is since kiwis are rich in sleep-encouraging antioxidant tryptophan, it may help you fall asleep if eaten 1 to 2 hours before sleep.
2-) Vitamin C in Kiwis Can Aid Sleep
Unlike tryptophan, vitamin C is known almost by everyone. It is arguably the most famous vitamin around the world.
While vitamin C is famous for mainly its immune-boosting effects, the evidence says this antioxidant may be beneficial for sleep, as well.
In one study researchers found that consuming vitamin C (100 mg BD) with the combination of vitamin E (400 IU BD) twice a day increased the sleep quality in obstructive sleep apnea patients (28).
In another study, researchers from the University of Pennsylvania found that those who slept less than 6 hours a night consumed less vitamin C than those who slept more than 6 hours (29).
Vitamin C may not help you fall asleep, but, it seems it can help you stay asleep.
When it comes to vitamin C, kiwi fruit is one of the highest (30). One 100 gr kiwifruit contains 92.7 mg vitamin C, according to USDA (31). Bear in mind, an adult person needs 65 to 90 milligrams (mg) of vitamin C a day (32).
The conclusion is kiwi, which is quite rich in vitamin C, may help you get a night of uninterrupted sleep.
3-) Potassium in Kiwis May Improve Sleep
Potassium is another nutrient that may explain why kiwi consumption is linked to better sleep.
Although scarce, there are some studies, suggesting that consuming enough potassium help individuals better cope with sleep disorders.
According to a study; low potassium levels in the body may decrease sleep time (33).
There is also one indirect way that potassium aid sleep. That is to reduce anxiety and stress symptoms.
If potassium is aiding sleep (as claimed), then eating potassium-rich foods, such as kiwi fruit, may offer a quality sleep.
A 100 gr kiwi fruit can give you 312 gr of potassium, which equates to 7 per cent of your daily potassium need (38).
A Study on The Effects of Kiwi Consumption on Sleep
In this section, we will examine the findings of a study, which is specifically about the effects of kiwi consumption on sleep.
In the study, researchers at Taiwan’s Taipei Medical University aimed to evaluate the potential effects of kiwi consumption on sleep.
Twenty-four subjects ( 2 males, 22 females between 20 to 55 years of age ) were recruited. Each participant consumed 2 kiwifruit 1 hour before their usual bedtime for a month.
Researchers used different techniques, such as; sleep diaries, sleep-quality questionnaires and also wristwatch – to gather parameters on the participants’ sleep patterns during the study.
After 4 weeks of kiwifruit consumption;
- Participants fell asleep faster. Sleep onset latency – the amount of time it takes to fall asleep – decreased by roughly 35%.
- The time spent in sleep after initially falling asleep improved by 5%.
- The total sleep time of participants increased by 13.4 %.
In light of the findings; researchers suggested: ” Kiwifruit consumption may improve sleep onset, duration, and efficiency in adults with sleep problems.”.
We can’t say that eating kiwifruit before bedtime will certainly improve your sleep! There are various factors that can affect a person’s sleep.
That being said, studies (although not enough at the moment), expert opinions and particular nutrients found in the kiwi fruit suggest that kiwi fruit has the potential to improve sleep.
Yet, more research is needed to understand the effects of kiwi consumption on sleep.
If you are suffering from sleep problems for a long time, we heavily recommend you to talk to your health care provider. Because prolonged sleep problems can wreak havoc on your both mental and physical health, leading to serious medical conditions.
However, if you think your sleep problems are manageable, then you can definitely give a chance to kiwifruit. With the sleep-promoting nutrients in it, kiwifruit may help you fall asleep faster and stay asleep longer.
Tarkan is an experienced medical writer ( currently more than 600 medical articles ) and also the founder of this website namely www.neededforhealth.com. His expertise in health stems from in-depth medical research and knowledge which he obtained over the course of many years.
Tarkan enjoys sharing factual knowledge on health, psychology and nutrition. He always aims to deliver evidence-based recommendations, provide links to related scientific studies.