Sleep & Nutrition Series

Can What You Eat Affect How You Sleep?

You can have the perfect pillow, a cool dark room and a sensible bedtime — and still lie there wide awake. Often the missing piece is the one most of us overlook: the food and drink we choose through the day. What you eat, and when you eat it, talks directly to the chemistry that runs your sleep.

+13%

more total sleep time for adults who ate two kiwifruit before bed for four weeks1

>1hr

of sleep lost when caffeine was taken even six hours before bedtime4

10%

better odds of good sleep with each step closer to a Mediterranean diet5

The 3-2-1 rule for an easy landing into sleep

One easy way to pull all of this together — just count back from bedtime. The times below are based on a typical 10:30pm lights-out, so shift them to match your own.

3

hours before — stop big meals

Give digestion time to settle. Heavy, fatty or sugary meals close to bed lead to lighter, more broken sleep.3

by 7:30pm
2

hours before — ease off drinks

Taper fluids so a full bladder doesn't wake you in the small hours — a common, avoidable sleep-wrecker.

by 8:30pm
1

hour before — screens off

Blue light from phones and tablets suppresses melatonin and delays your body clock, making sleep harder to find.10

by 9:30pm

Tip: fill that last screen-free hour with a light, sleep-friendly snack from the list above — a couple of kiwifruit or a banana work a treat.

Foods to favour, foods to watch

Everything above, boiled down to two short lists you can keep in mind at the shops.

Lean into these

  • Kiwifruit, tart cherries and other melatonin-friendly fruit1,2
  • Wholegrains, legumes, fruit and veg for fibre and deeper sleep3
  • Leafy greens, nuts and seeds for magnesium6
  • Oily fish, olive oil and a Mediterranean-style balance5
  • A lighter, earlier dinner so digestion settles before bed3

Go easy in the evening

  • Coffee, strong tea and energy drinks after mid-afternoon4
  • Heavy, fatty or spicy meals close to bedtime3,7
  • Sugary snacks, desserts and ice cream late at night3
  • Chocolate as a nightcap — it hides caffeine and theobromine8
  • A big glass of anything in the last hour before bed9

Water: plenty by day, gentle at night

Hydration is the quietest lever of all. In a large study spanning US and Chinese adults, people who slept less than six hours were more likely to be dehydrated — the two travel together.9 The trick is timing.

Through the day

Sip steadily so you reach the evening well-hydrated. Being short on fluids is linked to shorter, more restless sleep, and can leave you waking up dry and groggy.9 Pale-yellow is the colour you're aiming for.

In the last 2 hours

Start tapering. Drinking a lot right before bed is a leading cause of those bladder-driven wake-ups that fragment your sleep. A few sips are fine — just save the big glass for earlier in the evening.

How much coffee is still in your system at bedtime?

Caffeine doesn't switch off when your cup is empty — it fades by half roughly every five hours.11 In one study, a dose taken a full six hours before bed still cut more than an hour from people's sleep.4 Set your shots, the time of your last one and your bedtime, and we'll show what's still on board at lights-out.

Your coffee day

Every five hours or so, your body clears about half of the caffeine that's left.11 Slide to match your day.

Shots of coffee today
2 shots
16
Time of your last shot
2:00pm
8:00am6:00pm
Your bedtime
10:30pm
7:00pm1:00am
Still in your system at 10:30pm
Still on board 0.6 shots A little wired

≈ 49 mg of caffeine — 31% of each shot still active

About half a shot is still working at lights-out — worth nudging your last coffee a little earlier.

Your body builds sleep from what you feed it

Your body turns nutrients from food into the chemical messengers that wind you down: tryptophan becomes serotonin, and serotonin becomes melatonin, the hormone that tells your brain it's night. Feed it the right things and that process runs smoothly; lean on the wrong ones late in the day and you make it harder. Below are the foods worth leaning into, the ones worth rethinking, and a simple routine to pull it all together.

Six foods your sleep will thank you for

Kiwifruit

Falls asleep faster

Rich in serotonin and antioxidants. Adults with sleep problems who ate two kiwifruit an hour before bed for four weeks fell asleep faster, woke less, and slept about 13% longer.1

Lin HH, et al. Asia Pac J Clin Nutr. 2011.

Tart Cherries

Natural melatonin

Montmorency tart cherries are one of the few foods that naturally contain melatonin. Tart cherry juice lifted melatonin levels and improved sleep length and quality.2

Howatson G, et al. Eur J Nutr. 2012.

Wholegrains & Fibre

Deeper sleep

Fibre from wholegrains, legumes, fruit and veg does more than aid digestion. The more fibre people ate, the more deep, restorative slow-wave sleep they got.3

St-Onge MP, et al. J Clin Sleep Med. 2016.

Leafy Greens & Nuts

Magnesium

Spinach, almonds, pumpkin seeds and wholegrains all deliver magnesium, which helps the nervous system settle. In a trial, magnesium helped older adults fall asleep faster and wake less.6

Abbasi B, et al. J Res Med Sci. 2012.

Oily Fish

Mediterranean

Salmon, sardines and mackerel are cornerstones of the Mediterranean pattern. Adults whose diets leaned this way were significantly more likely to report good-quality sleep.5

Godos J, et al. Nutrients. 2019.

A Light Evening Meal

Timing matters

What you eat close to bed counts. A lighter, balanced dinner finished a couple of hours before bed gives your body the smoothest run into the night.3

St-Onge MP, et al. J Clin Sleep Med. 2016.

And a few that can quietly keep you up

These aren't "bad" foods — they're just better enjoyed earlier in the day than right before bed.

Spicy Foods

Body heat

To fall asleep, your core temperature needs to dip; capsaicin nudges it the other way. A spicy evening meal meant slower sleep onset and less deep sleep.7

Edwards SJ, et al. Int J Psychophysiol. 1992.

Citrus & Acidic Fruit

Reflux

Oranges, lemons and tomato-based foods are common heartburn triggers; lying down soon after can let acid creep back up. A daytime orange is a different, healthy story.

Recognised reflux and night-waking trigger in sleep-hygiene guidance.

Chocolate

Stimulants

Dark chocolate carries two stimulants: a little caffeine plus more theobromine — a 50g serve can hold over 200mg. Enjoy it, just not as a nightcap.8

Nehlig A. Br J Clin Pharmacol. 2013.

Ice Cream & Sweets

Sugar + fat

A late bowl of ice cream is a double hit of sugar and saturated fat — the exact combination linked to lighter, more broken sleep with more wake-ups.3

St-Onge MP, et al. J Clin Sleep Med. 2016.

Mostly a myth

What about bananas — do they keep you awake?

For most people it's the opposite. Bananas are packed with magnesium, potassium, vitamin B6 and tryptophan — the very raw materials your body uses to wind down and make melatonin,6 which is why they're a classic bedtime snack. The "keeps you awake" idea traces to tyramine, a mildly stimulating compound (also linked to more vivid dreams), plus their natural sugars — things only a small number of sensitive people notice. On balance, a banana 30-60 minutes before bed is a friend to your sleep, not an enemy of it.

Need a hand? Not sure where to start?

Our team helps Australians build the right sleep set-up every day - including NDIS orders. We're happy to talk it through.

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Scientific References

  1. Lin, H. H., Tsai, P. S., Fang, S. C., & Liu, J. F. (2011). Effect of kiwifruit consumption on sleep quality in adults with sleep problems. Asia Pacific Journal of Clinical Nutrition, 20(2), 169-174.
  2. Howatson, G., Bell, P. G., Tallent, J., Middleton, B., McHugh, M. P., & Ellis, J. (2012). Effect of tart cherry juice (Prunus cerasus) on melatonin levels and enhanced sleep quality. European Journal of Nutrition, 51(8), 909-916.
  3. St-Onge, M. P., Roberts, A., Shechter, A., & Choudhury, A. R. (2016). Fiber and saturated fat are associated with sleep arousals and slow wave sleep. Journal of Clinical Sleep Medicine, 12(1), 19-24.
  4. Drake, C., Roehrs, T., Shambroom, J., & Roth, T. (2013). Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed. Journal of Clinical Sleep Medicine, 9(11), 1195-1200.
  5. Godos, J., Ferri, R., Caraci, F., et al. (2019). Adherence to the Mediterranean diet is associated with better sleep quality in Italian adults. Nutrients, 11(5), 976.
  6. Abbasi, B., Kimiagar, M., Sadeghniiat, K., Shirazi, M. M., Hedayati, M., & Rashidkhani, B. (2012). The effect of magnesium supplementation on primary insomnia in elderly: a double-blind placebo-controlled clinical trial. Journal of Research in Medical Sciences, 17(12), 1161-1169.
  7. Edwards, S. J., Montgomery, I. M., Colquhoun, E. Q., Jordan, J. E., & Clark, M. G. (1992). Spicy meal disturbs sleep: an effect of thermoregulation? International Journal of Psychophysiology, 13(2), 97-100.
  8. Nehlig, A. (2013). The neuroprotective effects of cocoa flavanol and its influence on cognitive performance. British Journal of Clinical Pharmacology, 75(3), 716-727.
  9. Rosinger, A. Y., Chang, A. M., Buxton, O. M., Li, J., Wu, S., & Gao, X. (2019). Short sleep duration is associated with inadequate hydration: cross-cultural evidence from US and Chinese adults. Sleep, 42(2), zsy210.
  10. Chang, A. M., Aeschbach, D., Duffy, J. F., & Czeisler, C. A. (2015). Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proceedings of the National Academy of Sciences, 112(4), 1232-1237.
  11. Evans, J., Richards, J. R., & Battisti, A. S. (2024). Caffeine: pharmacology and elimination half-life (approximately 5 hours in healthy adults). StatPearls. StatPearls Publishing.