Kiwis Might Improve Your Sleep!

The number one question in sleep research is “Why do we sleep?” followed by the question “How much sleep do we need?” After literally hundreds of studies we still don’t know the best answer to either question. A few years ago I featured a large hundred thousand-person study which suggested that both short and long sleep duration were associated with increased mortality, with people getting around 7 hours of sleep living longest. Since then, a meta-analysis that included over a million people was published, and found the same thing.

We still don’t know, however, whether sleep duration is a cause or simply a marker of ill health. Maybe sleeping too little or too long does make you unhealthy—or maybe we see the associated shortened lifespan because being unhealthy causes you to sleep shorter or longer.

Similar work has now been published on cognitive function. After controlling for a long list of factors, men and women in their 50s and 60s getting 7 or 8 hours appeared to have the best short-term memory compared to those that got much more or much less. The same thing was just demonstrated with immune function: “both reduced and prolonged habitual sleep durations were associated with an increased risk of pneumonia.”

It’s easy to not get too much sleep—just set an alarm. But what if you’re having problems getting enough? What if you’re one of the 1 in 3 adults that suffer symptoms of insomnia? There are drugs like Valium that you can take for insomnia in the short term, but they have a number of adverse side effects. Non-pharmacological approaches such as cognitive behavioral therapy are often difficult, time-consuming, and not always effective. Wouldn’t it be great to have “natural treatments that can improve both sleep onset and help patients improve the quality of sleep while improving next-day symptoms over the long term?”

Enter “Effect of Kiwifruit Consumption on Sleep Quality in Adults With Sleep Problems.” Participants were given two kiwifruit an hour before bed every night for four weeks. Why kiwifruits? Well, people with sleep disorders tend to have high levels of oxidative stress, so maybe antioxidant rich foods might help. But all fruits and vegetables have antioxidants. Kiwifruits contain twice the serotonin of tomatoes—but it shouldn’t cross the blood-brain barrier. Kiwifruit has folate, and a deficiency might cause insomnia—but there’s a lot more folate in some other plant foods.

The reason they studied kiwifruits is because they got grant money from a kiwifruit company. And I’m glad they did because they found some really remarkable results: Significantly improved sleep onset, duration, and efficiency using both subjective and objective measurements. Participants went from sleeping 6 hours a night to 7—by just eating a few kiwifruit.

More on the power of kiwis in my videos Kiwifruit and DNA Repair and Kiwifruit for Irritable Bowel Syndrome, and more on sleep in Sleep & Immunity and Optimal Sleep Duration.

Videos on other natural remedies for various conditions include:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live year-in-review presentations Uprooting the Leading Causes of Death and More Than an Apple a Day.

Which Common Fruit Fights Cancer Better?
Raisins vs. Energy Gels for Athletic Performance
The Science on Acai Berries


Michael A.
Michael A.2 years ago


Tanya W.
Tanya W.2 years ago


Val M.
Val M.2 years ago


heather g.
heather g.2 years ago

That's worth monitoring, thanks ...

Mary L.
Mary L.2 years ago


Nora McKellar
Nora M2 years ago

as far as I can remember, I've always had trouble sleeping...i'm going to try this, what could it hurt right? lol

Shawn P.
Shawn P.2 years ago

Interesting, my husband should try this.

B J.
BJ J.2 years ago

Think the sale of kiwifruit "might" have skyrocketed for a while after this study?

Summerannie Moon
Summerannie M.2 years ago

love those little kiwi fruit. Good GI too

Chazz York jr
Chazz York2 years ago

And Kiwi actually tastes great too. I will have to remember this one.