Have you ever heard that eating kiwifruit before bed could help you sleep better?
Sounds weird, right?
But a new study with elite athletes suggests it might actually be true. Let’s talk about what they found and what it means for your sleep.
Background
Why study kiwis and sleep? We know that poor sleep is a big problem for athletes, and pretty much everyone else – it can hurt their training, make injuries more likely, and ruin performance. Whether dealing with elite athletes or general population clients trying to keep up. many often struggle to get quality sleep thanks to daily stressors, training, kids, family, etc.
Kiwifruit caught researchers’ attention because it’s a simple whole food that packs some sleep-friendly nutrients. In fact, kiwis naturally contain melatonin and its precursor - serotonin, both of which are linked to our circadian rhythm. They’re also rich in antioxidants which could help the body recover and unwind. Interestingly, earlier studies hinted that eating kiwis could improve sleep duration and quality in people with sleep troubles (PMID: 21669584).
So the question was: could kiwifruit help elite athletes sleep better and recover faster?
What the Researchers Did
The study was pretty straightforward. Researchers recruited 15 elite athletes (national-level sailors and middle-distance runners) to participate. The experiment lasted 5 weeks in total. First came a one-week baseline period to observe the athletes’ normal sleep and recovery patterns. Then, for the next 4 weeks, each athlete ate two kiwifruit about one hour before bedtime every night. That’s it – no other changes to their routine. During this time, the athletes kept daily sleep diaries and, both before and after the kiwi month, they filled out questionnaires about their sleep quality and how recovered or stressed they felt. This let the researchers compare “before vs. after” and see if the nightly kiwi habit made a difference.
What They Found
The results were pretty exciting. After four weeks of the kiwi bedtime snack, the athletes showed notable improvements compared to baseline:
Better sleep quality: The athletes rated their sleep quality higher after the kiwi intervention than before. In other words, their overall sleep satisfaction improved. (This was measured by a standard sleep quality index.)
Longer, sounder sleep: They also slept longer overall and woke up less often during the night, meaning their sleep was more uninterrupted. In fact, total sleep time went up and they spent more of the night actually sleeping, increasing sleep efficiency. They weren’t tossing and turning as much.
Improved recovery: The athletes even felt less stress. The study noted reductions in both general stress and sports-specific stress levels, indicating a better recovery-stress balance. Essentially, after a month of kiwis, the athletes’ bodies seemed to be recovering better from training – they were less frazzled and more refreshed.
All this from simply adding two kiwis before bed each night. No fancy pills, no special equipment – just a couple of pieces of fruit.
What It Means
So, what’s the big takeaway here? In plain language: a simple fruit snack at night made a real difference for these athletes’ sleep and recovery. This suggests that focusing on nutrition can be a natural way to improve sleep quality, not just for elite athletes but potentially for anyone struggling with sleep. If better sleep leads to better recovery and performance for athletes, imagine what it could do for the rest of us in our day-to-day lives. It’s a great example of a “food-first” solution – using whole foods instead of supplements – to tackle a common issue like poor sleep.
Why might kiwis help? Kiwifruit isn’t just tasty; it’s like a mini sleep cocktail in a natural package. As mentioned, kiwis have a notable amount of melatonin, which is the hormone that helps regulate your sleep-wake cycle (your internal body clock) and tells your body it’s time to wind down. They also contain antioxidants (like vitamins C & E) that help reduce oxidative stress in your body, which might improve sleep and recovery. Some experts point out kiwis have serotonin and folate too, which could play supportive roles in sleep health. In short, a kiwi brings a lot of sleep-friendly nutrients to the table.
One cool implication: unlike using a supplement, you’re also getting vitamins, fiber, and other health benefits.
A few caveats: Remember that this was a relatively small study (just 15 athletes). It was also done during a pandemic lockdown, so the researchers had to rely on self-reported sleep diaries and questionnaires – they didn’t use high-tech sleep trackers or lab sleep studies in this trial. The study’s authors acknowledge these limitations and recommend doing further research with more athletes, and using objective sleep measurements, in a controlled trial setting. In other words, we need bigger studies to confirm just how effective kiwifruit is for improving sleep, and to make sure the results apply to different groups of people.
That said, the findings are promising and add to the slowly growing evidence supporting kiwis as a potential sleep aid. Kiwis are inexpensive, easy to find, and generally safe to eat. For most, there’s basically no downside to giving this a try. If you’re an athlete looking for an edge, or just someone who wants to sleep better, it might be worth conducting your own little experiment: try eating two kiwis about an hour before bed for a few weeks and see if you notice a difference.. Worst case, you’ve added some extra fruit to your diet; best case, you might sleep more soundly and wake up feeling a bit more refreshed.
Doherty R, Madigan S, Nevill A, Warrington G, Ellis JG. The Impact of Kiwifruit Consumption on the Sleep and Recovery of Elite Athletes. Nutrients. 2023 May 11;15(10):2274. doi: 10.3390/nu15102274. PMID: 37242157; PMCID: PMC10220871.
Lin HH, Tsai PS, Fang SC, Liu JF. Effect of kiwifruit consumption on sleep quality in adults with sleep problems. Asia Pac J Clin Nutr. 2011;20(2):169-74. PMID: 21669584.
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