The clocks fell back last Sunday, and you were promised an extra hour of sleep. Instead, it's 10:45 at night, the lights have been off for half an hour, and you're still checking the time on your phone. You skipped the late coffee. You went to bed on time. Sleep just isn't coming.
This is not your fault. A rough week of sleep can have a dozen causes, and most of them have nothing to do with willpower. But one small bedtime habit has an actual study behind it: two kiwis, eaten about an hour before bed.
Two kiwis, one hour, four weeks
Researchers at Taipei Medical University asked 24 adults aged 20 to 55, all with self-reported sleep problems, to eat 2 green kiwifruit 1 hour before bed every night for 4 weeks. The results were published in the Asia Pacific Journal of Clinical Nutrition.
According to the participants' sleep diaries, the time it took to fall asleep dropped from about 34 minutes to about 20, a decrease of 35%. Total sleep time rose by about 13%, and time spent awake after first falling asleep went down. A wrist sensor worn at night also recorded longer total sleep.
Why kiwis? The researchers pointed to what the fruit contains: serotonin, antioxidants such as vitamins C and E, and folate. They suggested these might play a role, but the study didn't test any of them directly.
How to try the bedtime kiwi
If you want to see whether the habit helps you, copy the study as closely as you can:
- Pick green kiwis. The study used 2 medium Hayward green kiwifruit.
- Eat them about 1 hour before bed. Peel and slice them, or cut them in half and scoop with a spoon.
- Give it 4 weeks. Participants ate them every night for a month. One night tells you very little.
- Keep a simple sleep diary. Write down when you turned off the light and roughly when you fell asleep, the same kind of record the participants kept.
- Keep the basics steady. The CDC recommends at least 7 hours of sleep for adults, a regular bedtime, no caffeine in the afternoon or evening, and putting screens away about 30 minutes before bed. Kiwis don't replace any of that.
Plan B if fruit right before bed doesn't sit well: eat the kiwis with dinner. In a 2023 trial at Massey University, 24 young men ate 2 kiwis right after dinner, about 4 hours before bed. The researchers linked kiwi, fresh or dried, to improvements in some aspects of sleep quality compared with water, but the effects were limited and objective sleep measures were mixed. Kiwis also work earlier in the day, blended into a pineapple kiwi smoothie bowl, though that's not what either study tested.
Why 24 sleepers aren't the final word
The Taipei study was small: 24 people, 22 of them women. It had no control group, so there's no way to know how much of the improvement came from the kiwis and how much from simply paying attention to sleep for a month. The authors acknowledge this.
It was also supported by Zespri International, a kiwifruit marketer. The biggest change, in time to fall asleep, came from participants' own diaries. The wrist sensor showed a smaller drop that wasn't statistically significant.
So kiwis are a low-risk experiment, not a treatment. If fruit like kiwi has ever made your mouth itch or swell, skip it. And if trouble sleeping lasts for weeks, or you snore heavily or wake up exhausted, talk to your doctor: a sleep problem can have causes a bedtime snack won't fix.
Two green kiwis, an hour before lights out, every night for a month. That's the trick.
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