Food & Sleep
4 STAGES · 32 FINDINGS · 29 STUDIES
Foods and drinks for each part of your sleep.
How food affects your sleep depends on the part of the night. Here is what each food and drink did to deep sleep, REM, falling asleep and night waking, graded by evidence.
32
Food and sleep findings
7
Backed by strong evidence
7
Tested and found no change
29
Peer-reviewed studies
The quick answer
Food moves one stage at a time.
What helps and what hurts each part of sleep. Tap any food for the study.
Deep sleep
REM
Falling asleep
Night waking
Deep sleep
- Lower carb diet About 8 min more deep sleep
- Fiber More fiber, more deep sleep
- Very low carb (keto) 18% of the night vs 14%
- Caffeine About 11 min less deep sleep
- A week of junk food Same minutes, shallower on EEG
- Saturated fat More saturated fat, less deep sleep
- Under-eating for training Fewer hours of deep sleep when under-fueled
- Spicy dinner Less deep sleep, more time awake
REM
- Higher carb diet About 9 min more REM
- Alcohol Starts 18 min later, runs 11 min shorter
- High protein, lower carb About 9 min less REM, 15 min later
- Daytime fasting 18.6% of sleep vs 25.6%
Falling asleep
- High GI carbs, 4h before bed 9.0 min vs 17.5 min
- Caffeine About 9 min slower
- High protein, lower carb About 4 min slower
- Energy drinks About 1.8x the risk of 2h+ to fall asleep
Night waking
- Tart cherry juice About 17 min less awake
- Fruit and vegetables 16% less fragmented at 5 cups a day
- Caffeine About 12 min more awake
- Late dinners, 4 nights 29 min awake vs 16 min
- Sugar More arousals that night
- Eating within 1h of bed 2 to 2.6x the odds of 30+ min awake
Foods with no clear or a mixed effect are listed in each section below.
How the grades work
- Strong A meta-analysis or several RCTs.
- Moderate One solid controlled study.
- Observational A link in survey or tracking data, not a tested cause.
- Weak Tiny or uncontrolled.
Free 7-Day Trial
Find the foods that change your sleep.
Every number on this page is a study average. Kygo lines up your own meals, caffeine and alcohol with the deep sleep, REM and wake-ups your wearable records, night after night.
Works with
Oura
Apple
Fitbit
Garmin
WHOOP
Polar
Health
Deep sleep (N3)
Foods that affect deep sleep.
Caffeine is the only strong-evidence lever, and it costs you deep sleep. Lower carb eating adds a little.
9 findings
3 help
5 hurt
1 no change
Helps first, then hurts
Lower carb diet
About 8 min more deep sleep
Moderate
Lower carb gave about 8 min more deep sleep. It is the same meta-analysis that found more REM on higher carb, so carbs look like a trade between the two stages rather than a win or a loss.
- Study
- Meta-analysis of 11 small studies (27 trial arms).
- Evidence
- Moderate: one solid controlled study.
Fiber
More fiber, more deep sleep
Observational
More fiber on a free eating day predicted more deep sleep that night. A second lab study found the same link.
- Study
- Observational, 26 people in a sleep lab; repeated in 46 people, lab PSG.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Very low carb (keto)
18% of the night vs 14%
Weak
Deep sleep was about 18% of the night vs 14% on a high carb, low fat diet.
- Study
- 14 healthy men, PSG, not randomized (the normal diet night always came first).
- Evidence
- Weak: tiny or uncontrolled.
Caffeine
About 11 min less deep sleep
Strong
About 11 min less deep sleep on average across studies. In the trial, 400mg (about 4 standard cups of coffee) 4h before bed cut deep sleep by 29.7 min, and still cut it by 20.6 min at 12h. 100mg had no measurable effect at any timing.
- Study
- Meta-analysis of 24 studies; dose detail from a double-blind crossover in 23 men on a home forehead EEG device.
- Evidence
- Strong: a meta-analysis or several RCTs.
A week of junk food (high fat, high sugar)
Same minutes, shallower on EEG
Moderate
Compared with a low fat, low sugar week, time in deep sleep did not change but the deep sleep was shallower on EEG. Our read: a wearable would probably show the same deep sleep minutes.
- Study
- Randomized crossover, 15 healthy men, lab PSG, same calories in both weeks.
- Evidence
- Moderate: one solid controlled study.
Saturated fat
More saturated fat, less deep sleep
Observational
A higher share of calories from saturated fat on a free eating day predicted less deep sleep that night.
- Study
- Observational, 26 people, sleep lab PSG.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Not eating enough for your training
Fewer hours of deep sleep when under-fueled
Observational
Swimmers who ate more relative to their training got more hours of deep sleep. 69% were under-eating. Deep sleep as a share of the night did not change.
- Study
- Observational, 26 college swimmers, WHOOP plus MyFitnessPal logs over 3 matched days.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Spicy dinner (Tabasco and mustard)
Less deep sleep, more time awake
Weak
Less deep sleep and more time awake, possibly from higher body temperature early in the night. Tiny study.
- Study
- 6 men, PSG.
- Evidence
- Weak: tiny or uncontrolled.
Alcohol (high dose, about 5 drinks)
More early, less late, same total
Moderate
Breath alcohol was about 0.08% at lights out. More deep sleep in the first half of the night, less in the second half, more time awake. Total deep sleep did not go up and REM went down. McCullar saw the same over 3 nights in a row.
- Study
- Lab PSG in 22 people aged 18 to 21; the same pattern in a randomized crossover of 30 adults over 3 nights.
- Evidence
- Moderate: one solid controlled study.
Every deep sleep factor, not just food
REM sleep
Foods that affect REM sleep.
Alcohol is the clearest REM effect. Carbs tilt the night toward REM; protein and daytime fasting tilt it away.
7 findings
1 help
3 hurt
3 no change
Helps first, then hurts
Higher carb diet
About 9 min more REM
Moderate
High carb meals or diets gave about 9 min more REM vs low carb. Low carb shifted sleep toward deep sleep instead. Not every study agrees: one small cyclist trial and one observational study tied protein or fat, not carbs, to more REM.
- Study
- Meta-analysis of 11 small studies (single meals to 4 day diets), 179 people.
- Evidence
- Moderate: one solid controlled study.
Alcohol
Starts 18 min later, runs 11 min shorter
Strong
REM started about 18 min later and ran about 11 min shorter. REM delay began around 2 drinks and REM loss around 3, and each extra drink cut more.
- Study
- Meta-analysis of 27 studies in healthy adults.
- Evidence
- Strong: a meta-analysis or several RCTs.
High protein, lower carb diet
About 9 min less REM, 15 min later
Moderate
About 9 min less REM than a higher carb diet with the same calories. Time to first REM also came about 15 min later on the high protein diet.
- Study
- Randomized crossover, 24 healthy young men, home PSG, 3 days per diet.
- Evidence
- Moderate: one solid controlled study.
Daytime fasting (Ramadan style)
18.6% of sleep vs 25.6%
Moderate
REM was 18.6% of sleep while fasting vs 25.6% before, with sleep times and calories held fixed. Fasting outside Ramadan cut REM by a similar amount. The 3:30am wake up to eat may play a part.
- Study
- Two small PSG studies of 8 healthy men each.
- Evidence
- Moderate: one solid controlled study.
Caffeine
REM unchanged
Strong
No change in REM minutes, REM share or time to first REM. Caffeine cuts deep sleep instead (see deep sleep above).
- Study
- Meta-analysis, 17 to 19 studies for REM outcomes.
- Evidence
- Strong: a meta-analysis or several RCTs.
Late dinner (10pm vs 6pm)
20.8% of sleep vs 20.6%
Moderate
REM was 20.8% vs 20.6% of sleep. Eating dinner an hour before bed did not reduce REM.
- Study
- Randomized crossover, 20 healthy adults, lab PSG.
- Evidence
- Moderate: one solid controlled study.
Almonds (60g a day, 5 months)
No REM difference
Moderate
Industry-funded
No difference in REM minutes or time to first REM vs an equal calorie snack. People eating almonds did report sleeping better.
- Study
- RCT, 175 adults with poor sleep, home PSG.
- Evidence
- Moderate: one solid controlled study.
- Funding
- Funded by the Almond Board of California.
Every REM sleep factor, not just food
Falling asleep (sleep latency)
Foods that affect how fast you fall asleep.
Caffeine slows you down by about 9 minutes. A high GI carb dinner about 4 hours before bed speeds you up.
7 findings
1 help
3 hurt
3 mixed
Helps first, then hurts
High GI carb meal (4h before bed)
9.0 min vs 17.5 min
Moderate
A jasmine rice dinner 4h before bed: 9.0 min to fall asleep vs 17.5 min on low GI rice. The same meal 1h before bed gave 14.6 min.
- Study
- Randomized order crossover, 12 healthy men.
- Evidence
- Moderate: one solid controlled study.
Caffeine
About 9 min slower
Strong
Adds about 9 min to falling asleep on average, and dose or timing did not change that.
- Study
- Meta-analysis, 19 studies for this outcome, mostly PSG.
- Evidence
- Strong: a meta-analysis or several RCTs.
High protein, lower carb diet
About 4 min slower
Moderate
Took about 4 min longer to fall asleep than a higher carb diet with the same calories. On the higher carb diet it dropped from 15.8 to 11.4 min.
- Study
- Randomized crossover, 24 healthy young men, home PSG, 3 days per diet.
- Evidence
- Moderate: one solid controlled study.
Energy drinks
About 1.8x the risk of 2h+ to fall asleep
Observational
Daily drinkers had about 1.8 to 1.9x the risk of taking over 2 hours to fall asleep vs never or seldom. Risk rose from just 1 to 3 times a month. Adjusted for age only.
- Study
- Observational, 53,226 Norwegian students, self-report.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Alcohol
Only at about 5+ drinks
Strong
Only about 5+ drinks shortened time to fall asleep, while REM was disrupted from about 2 drinks.
- Study
- Meta-analysis of 27 studies in healthy adults.
- Evidence
- Strong: a meta-analysis or several RCTs.
Alpha-lactalbumin drink (milk protein) before bed
5 of 8 studies positive
Moderate
In the rugby trial, 11.6 and 17.0 min to fall asleep vs about 21 to 22 min on a whey control. Two other trials (6 + 6 cyclists, and 24 adults over 7 nights) found no effect.
- Study
- Review of 8 studies, 5 positive; RCT in female rugby players on wrist actigraphy, 12 with usable data.
- Evidence
- Moderate: one solid controlled study.
Mediterranean diet
Questionnaires yes, trackers no
Observational
All 3 questionnaire studies linked it to falling asleep faster. A 533 person wrist tracker study and a 41 person 5 week feeding trial found no measured change.
- Study
- Review of 20 studies, plus a wrist tracker cohort and a feeding RCT.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Fallah 2024Verkaar 2024O'Connor 2018
Every sleep latency factor, not just food
Staying asleep (WASO)
Foods that affect night waking.
Caffeine adds about 12 minutes awake. Late dinners split: one night did nothing, four nights added waking.
9 findings
2 help
4 hurt
3 no change
Helps first, then hurts
Tart cherry juice
About 17 min less awake
Moderate
Industry-funded
62 min awake on cherry vs 79 min on placebo, about 17 min less. Later trials were mixed: a 2024 capsule trial (n=34, EEG headband and Fitbit) and a 2022 diary trial in 44 healthy adults found nothing, while an 8 person juice trial in older adults with insomnia found 84 min more sleep in the lab and a 2012 trial in 20 healthy adults found more sleep on actigraphy.
- Study
- RCT crossover, 15 older adults with insomnia, sleep diary.
- Evidence
- Moderate: one solid controlled study.
- Funding
- Funded by the juice maker (funded entirely).
Fruit and vegetables
16% less fragmented at 5 cups a day
Observational
5 cups a day vs none lined up with 16% less fragmented sleep. The link weakened and was no longer significant after accounting for total calories.
- Study
- Observational, 34 mostly young men, 201 nights, wrist actigraphy.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Caffeine
About 12 min more awake
Strong
About 12 extra minutes awake during the night.
- Study
- Meta-analysis, 13 studies for this outcome, +11.8 min.
- Evidence
- Strong: a meta-analysis or several RCTs.
Late dinner (1h vs 5h before bed), 4 days
29 min awake vs 16 min
Moderate
Industry-funded
Time awake was 29 vs 16 min, with more arousals and about 26 min less sleep. Time to fall asleep did not change. Disagrees with the single night lab study above.
- Study
- Randomized crossover, 13 young women, home EEG.
- Evidence
- Moderate: one solid controlled study.
- Funding
- Funded by Yazuya, a food company.
Sugar
More arousals that night
Observational
A higher share of calories from sugar on a free eating day predicted more arousals that night.
- Study
- Observational, 26 people, sleep lab PSG.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Eating within 1h of bed
2 to 2.6x the odds of 30+ min awake
Observational
About 2 to 2.6x the odds of reporting 30+ min awake in the night. The same people also slept 25 to 35 min longer.
- Study
- Observational, 124,239 people, US time use survey.
- Evidence
- Observational: a link in survey or tracking data, not a tested cause.
Alcohol
No clear change in time awake
Strong
Pooled lab studies found no clear change in time awake (+4 min, 12 studies) or sleep efficiency (-0.7%, 24 studies), at any dose. One large tracker study saw about 1 point lower efficiency.
- Study
- Meta-analysis of lab sleep studies in healthy adults, plus a tracker study of 785 people.
- Evidence
- Strong: a meta-analysis or several RCTs.
Late dinner (1h vs 5h before bed), single night
No change in time awake
Moderate
In a controlled test, eating late did not change time awake, sleep efficiency or sleep stages. The survey link below may be about who eats late, not the food.
- Study
- Randomized crossover, 20 healthy adults, lab PSG.
- Evidence
- Moderate: one solid controlled study.
Almonds (60g a day, 5 months)
Only self-reported sleep improved
Moderate
Industry-funded
No difference in time awake or sleep efficiency vs an equal calorie snack. Only self-reported sleep efficiency improved.
- Study
- RCT, 175 adults with poor sleep, home PSG.
- Evidence
- Moderate: one solid controlled study.
- Funding
- Funded by the Almond Board of California.
Every staying asleep factor, not just food
Before you test it on yourself
What your tracker can and can't see.
Most effects here are 5 to 15 minutes, easy to lose in night-to-night noise.
Minutes are not depth
A week of junk food left deep sleep minutes unchanged but made it shallower on EEG. A ring or watch counts minutes, so it would likely miss this.
Brandão 2023, randomized crossover, n=15
One night can mislead
One late dinner changed nothing; four in a row added about 13 minutes awake. Test a food over several nights, not one.
Gu 2020, n=20 · Enomoto 2026, n=13
Feeling better is not measuring better
Almond eaters said they slept better, but their measured sleep did not change. The Mediterranean diet showed the same gap.
Desai 2026, n=175 · Fallah 2024 · Verkaar 2024 · O'Connor 2018
Keep exploring
Related tools.
More free, evidence-based tools to get the most out of your wearable.
Sleep stages overnight
REM Sleep Factor Explorer
37 research-backed factors that raise, lower or don't change REM sleep, with mechanisms.
Sleep · 37 factors
Open
Sleep staging vs PSG
Oura
Apple
Fitbit
Garmin
Most Accurate Sleep Tracker
Which wearable is most accurate for sleep vs a lab PSG? Compare 7 devices head to head.
Wearables · 14 sources
Open
Graded by evidence
Supplements by Metric
Pick a wearable metric and see which of 27 supplements the research actually supports.
Nutrition · 28 sources
Open
FAQ
Common questions.
How does food affect your sleep?
Mostly one stage at a time. Caffeine costs deep sleep (about 11 minutes on average across 24 studies), slows falling asleep by about 9 minutes and adds about 12 minutes awake, but leaves REM unchanged. Alcohol costs REM (it starts about 18 minutes later and runs about 11 minutes shorter) without adding any deep sleep overall. Carbohydrate tilts the night toward REM, while lower carb eating tilts it toward deep sleep. Many popular claims, such as almonds, a late dinner on a single night, or a Mediterranean diet on a sleep tracker, showed no measured change.
What foods help you get more deep sleep?
The best-tested food effect on deep sleep is a negative one: caffeine cuts it by about 11 minutes on average, and 400mg (about 4 cups of coffee) still cut it by 20.6 minutes when taken 12 hours before bed, while 100mg had no measurable effect. On the positive side, lower carb eating gave about 8 minutes more deep sleep in a meta-analysis of 11 small studies, and in lab studies a higher fiber, lower saturated fat day predicted more deep sleep that night, though that is an observational link. A very low carb (keto) diet raised deep sleep from about 14% to 18% of the night in one small, non-randomized study.
What foods increase REM sleep?
Higher carb meals and diets gave about 9 minutes more REM than low carb in a meta-analysis of 11 small studies. Not every study agrees, but a controlled trial found a high protein, lower carb diet cut REM by about 9 minutes and pushed the first REM period about 15 minutes later. The biggest REM effects run the other way: alcohol delays and shortens REM from around 2 to 3 drinks, and daytime fasting dropped REM from 25.6% to 18.6% of sleep. Caffeine, a late dinner and almonds did not change REM.
Does eating late at night affect sleep?
The controlled evidence is split. In a randomized lab study, eating dinner at 10pm instead of 6pm for one night did not change REM, deep sleep, time awake or sleep efficiency (Gu 2020, n=20). Over 4 days, eating 1 hour instead of 5 hours before bed raised time awake from 16 to 29 minutes and cut about 26 minutes of sleep (Enomoto 2026, n=13, funded by a food company). A survey of 124,239 people linked eating within an hour of bed to 2 to 2.6x the odds of 30+ minutes awake, but those people also slept 25 to 35 minutes longer, so it may reflect who eats late rather than the food.
How long before bed should you stop caffeine?
It depends heavily on dose. In a double-blind trial, 400mg of caffeine (about 4 standard cups of coffee) cut deep sleep by 29.7 minutes when taken 4 hours before bed and still cut it by 20.6 minutes when taken 12 hours before bed. 100mg had no measurable effect at any timing. Across studies, caffeine adds about 9 minutes to falling asleep, and in that pooled data dose and timing did not change the effect.
Does alcohol help you sleep?
It helps you fall asleep only at a high dose, about 5 or more drinks, while REM is disrupted from about 2 drinks: REM starts about 18 minutes later and runs about 11 minutes shorter on average across 27 studies. At about 5 drinks, deep sleep rises in the first half of the night and falls in the second half, so the total does not go up, and time awake rises. Pooled lab studies found no clear change in total time awake across the night.
Does tart cherry juice help you sleep?
One crossover trial in 15 older adults with insomnia found about 17 minutes less time awake on tart cherry juice than placebo (62 vs 79 minutes), but it was funded entirely by the juice maker and used a sleep diary. Later trials are mixed: a 2024 capsule trial using an EEG headband and Fitbit, and a 2022 diary trial in 44 healthy adults, found nothing, while a small trial in older adults with insomnia and a 2012 actigraphy trial found more sleep.
Will my wearable show these effects?
Some of them. Effects on time to fall asleep, time awake and stage minutes are what a ring or watch estimates, but most of the changes here are 5 to 15 minutes, which is within a wearable's night-to-night noise, so test a food over several nights, not one. Some changes a wearable cannot see at all: a week of junk food made deep sleep shallower on EEG without changing deep sleep minutes. Kygo lines up your logged meals, caffeine and alcohol with your own sleep data across many nights, which is the practical way to see whether a food matters for you.
Sources
Every finding, traceable.
Each card links the paper behind a finding above. The tag shows the study design, with industry funding first where it applies.
Meta-analysis
Carbohydrate intake and sleep stages: meta-analysis of 11 studies
Vlahoyiannis et al., Nutrients, 2021 · n=179
Observational
Fiber, saturated fat and sugar on a free-eating day vs that night's sleep
St-Onge et al., Journal of Clinical Sleep Medicine, 2016 · n=26, lab PSG
Observational
Fiber intake and slow-wave sleep: replication in a second lab sample
Spaeth et al., SLEEP, 2017 · n=46, lab PSG
Non-randomized PSG study
Very low carb (ketogenic) vs high carb, low fat diet: deep sleep share
Afaghi et al., 2008 · n=14 healthy men, PSG, normal-diet night always first
Meta-analysis
Caffeine and sleep: meta-analysis of sleep stages, sleep onset and time awake
Gardiner et al., Sleep Medicine Reviews, 2023
Double-blind crossover
Caffeine dose and timing before bed: 100mg vs 400mg at 12, 8 and 4 hours
Gardiner et al., SLEEP, 2025 · n=23 men, home forehead EEG
Randomized crossover
A week of high fat, high sugar food vs low fat, low sugar food at the same calories: deep sleep EEG
Brandão et al., Obesity, 2023 · n=15 healthy men, lab PSG
Observational
Energy intake relative to training load and WHOOP sleep in college swimmers
Lundstrom et al., Journal of the International Society of Sports Nutrition, 2026 · n=26
Small PSG study
Spicy dinner (Tabasco and mustard): deep sleep, time awake and body temperature
Edwards et al., International Journal of Psychophysiology, 1992 · n=6 men
Controlled PSG study
High-dose alcohol (about 5 drinks) before bed: first vs second half of the night
Chan et al., Alcoholism: Clinical & Experimental Research, 2013 · n=22 aged 18 to 21
Randomized crossover
Alcohol on 3 nights in a row: sleep stages across the night
McCullar et al., SLEEP, 2024 · n=30, 3 nights lab PSG
Meta-analysis
Alcohol and sleep architecture in healthy adults: meta-analysis of 27 studies
Gardiner et al., Sleep Medicine Reviews, 2025
Randomized crossover
High protein, lower carb diet vs higher carb diet at equal calories: sleep stages
Saidi et al., Nutrients, 2022 · n=24 young men, home PSG
Controlled PSG study
Ramadan-style daytime fasting with sleep times and calories held fixed: sleep architecture
BaHammam et al., Behavioral and Brain Functions, 2013 · n=8 men
Controlled PSG study
Daytime fasting outside and during Ramadan: effects on REM sleep
Roky et al., Journal of Sleep Research, 2001 · n=8 men
Randomized crossover
Late dinner (10pm) vs routine dinner (6pm): sleep stages and time awake
Gu et al., Journal of Clinical Endocrinology & Metabolism, 2020 · n=20, lab PSG
Industry-funded · RCT
Almonds (60g a day for 5 months) vs an equal-calorie snack in adults with poor sleep
Desai et al., Frontiers in Nutrition, 2026 · n=175, home PSG · funded by the Almond Board of California
Crossover trial
High vs low glycemic index rice dinner, 4 hours or 1 hour before bed: time to fall asleep
Afaghi et al., American Journal of Clinical Nutrition, 2007 · n=12 healthy men
Observational
Energy drink use and sleep in Norwegian students
Kaldenbach et al., BMJ Open, 2024 · n=53,226, self-report
Systematic review
Alpha-lactalbumin and sleep: review of 8 studies
Barnard et al., Journal of Sleep Research, 2024
RCT
Alpha-lactalbumin drink before bed in female rugby players: sleep onset on actigraphy
Gratwicke et al., Biology of Sport, 2022 · 12 with usable data
Systematic review
Mediterranean diet and sleep: review of 20 studies
Fallah et al., BMC Nutrition, 2024
Observational
Mediterranean diet and wrist-tracker sleep in a 533-person cohort
Verkaar et al., Sleep Medicine, 2024 · n=533
Feeding RCT
Five weeks of a Mediterranean-style diet: measured sleep
O'Connor et al., Journal of Nutrition, 2018 · n=41
Industry-funded · RCT
Tart cherry juice vs placebo in older adults with insomnia
Pigeon et al., Journal of Medicinal Food, 2010 · n=15, sleep diary · funded entirely by the juice maker
Observational
Daily fruit and vegetable intake and sleep fragmentation over 201 nights
Boege et al., Sleep Health, 2025 · n=34, wrist actigraphy
Industry-funded · crossover
Late dinner (1h vs 5h before bed) for 4 days: time awake on home EEG
Enomoto et al., Journal of Physiological Anthropology, 2026 · n=13 young women · funded by Yazuya, a food company
Observational
Eating within an hour of bed and night waking in the US time use survey
Iao et al., British Journal of Nutrition, 2022 · n=124,239
Observational
Evening alcohol, caffeine and nicotine vs actigraphy sleep efficiency
Spadola et al., SLEEP, 2019 · n=785
Show all 29 sources
Kygo Health
Stop Guessing. Start Knowing.
Home How It Works Blog Contact Privacy Terms
This content is for informational purposes only and is not medical advice. The findings are averages from study groups, many of them small, and may not apply to you. Talk to a qualified healthcare provider before changing your diet, especially if you have a sleep disorder or a medical condition.
Data from peer-reviewed studies, meta-analyses and reviews, each linked above. Last updated October 2026.
© 2026 Kygo Health LLC. All rights reserved.
From the blog
Show fewer sources
Keep reading.
The long-form, evidence-based articles behind this tool.
Sleep
How Food Affects Your Sleep
Foods, drinks and eating patterns tested against each part of sleep, one table per stage, with every finding graded.
15 min read
Read
Sleep
Caffeine and Sleep: Finding Your Personal Cutoff Time
The standard advice is to stop by 2 PM. The research says your personal cutoff can sit hours either side of that rule.
11 min read
Read
HRV & Recovery
Why Does Alcohol Crush Your HRV (and How Long Until It Recovers)
Even moderate drinking suppresses HRV for two to four days. How alcohol does it, and why recovery takes longer than you think.
7 min read
Read