Two Kiwifruit an Hour Before Bedtime

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, 100,000-person study which suggested that both short and long sleep duration were associated with increased mortality, with people getting around seven hours of sleep living longest (See Optimal Sleep Duration). 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 us unhealthy—or maybe we see the associated shortened lifespan because being unhealthy causes us 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 seven or eight 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 where “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 we’re having problems getting enough? What if we’re one of the one in three adults that suffer symptoms of insomnia? There are sleeping pills like Valium that we can take 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?”

What about a study on kiwifruit, featured in my video, Kiwifruit for Insomnia? 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 an average of six hours a night to seven—by just eating a few kiwifruits.

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.

Videos on other natural remedies for various conditions include:

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my videos for free by clicking here and watch my full 2012 – 2015 presentations Uprooting the Leading Causes of Death, More than an Apple a Day, From Table to Able, and Food as Medicine.

Image credit: Peter Miller / Flickr

  • Kitsy Hahn

    Ah, so they got some grant $$ from a kiwifruit company, huh? Other than the fact that I have no trouble sleeping at night (am even able to take a short nap during the afternoon), I’d never eat anything an hour before bedtime, anyway. Heck, I’d have brushed/flossed my teeth hours earlier, soon after I had my last meal of the day — am not about to sully them up with yet more food.

    I’m thinking a lot of those folks who have problems with insomnia just don’t get enough physical exercise during the daytime hours. Too much butt sitting is not healthy.

  • LynnCS

    I hear that kiwi is a kin to banana. I can’t eat banana, so I haven’t wanted to pursue the kiwi. Maybe someone can tell me what the relationship is. I can see it in the cross section a bit.

    Also, about eating before bed, I learned that eating an apple before bed, eliminated that GERD action at night. Guess what? IT WORKS! Not the topic, but thought I’d pass that along!

    • Theresa

      I also concur that an apple before bed will calm down digestive problems like GERD.

  • baby_grand

    I like to take days of ‘forced sleep’ where I sleep longer than per regular schedule. I often find 10-12 hours refreshing and energizing. My mind is clearer, appetite reduced, attitude much calmer after one of these bouts of sleep. Whether I am deeply asleep or not, just being rested is wonderful for me. I think for me the purpose of sleep is to remove stress and allow the body to function without need of constant reaction and departure from homeostasis. In that state, renewals, readjustments, restorations can happen I didn’t know I needed.

  • Smith

    Bananas are better. Two bannas before bed time

  • Ellen Lederman

    As much as I’d love to believe that two kiwis are all you need for a good night’s sleep….I’d have to see a better study to be convinced. Participants knew they were eating kiwi and that their sleep was being monitored—could be the placebo effect. Would have liked a comparison—-kiwi versus eating an ounce of walnuts or an apple, for example. I’m not sure this research is up to Dr. G’s usual standards…

    • Yes, double blind studies are very hard to near impossible with whole foods.

      While you’re waiting for an independent study to confirm this, have you got anything to lose by trying a couple of kiwis?

  • Giulia

    I’m 9 months in a vegan pregnancy, never had any problems at all, just now i start to find sleeping a bit difficult. Yesterday night i couldn’t sleep, i got up ad ate 6-7 kiwis, just cause i crave them.
    Slept soundly

  • Joe

    April fools!

  • Annie

    what if I sleep to much and alarm doesn’t work? :/ I can’t get up, I sleep 12 hours or more.