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Does a short night make you eat more? Slide your sleep and see what the studies found

Does a short night make you eat more? Researchers have tested it, and the link looks real, but the size varies a lot between people.

Slide your usual hours of sleep against the 7 to 9 hour guidance, then flip between lab studies where sleep was cut (about 385 kcal more a day on average) and a home trial where sleep was extended (about 270 kcal a day less). We explain what the numbers do and do not show, the small habits the NHS suggests, and when to ask a doctor.

A crescent moon above three horizontal bars, one marked at the seven-hour line, beside the title

Why would a short night change what you eat?

Most people have noticed it: after a bad night you want something sugary, something salty, something now. Researchers have tested whether that is just a feeling or a real change in how much people eat. The short answer is that sleep and appetite are linked, the link looks real in trials, and the size of it varies a lot between people and studies.

Below you can set how long you usually sleep and compare it with the guidance, then flip between the two kinds of study that give us the numbers.

What the studies found

A 2016 review pooled 11 small experiments, 172 people in all, where researchers deliberately cut sleep and then measured what people ate. On average they ate about 385 kcal more the next day. The mix of what they ate shifted slightly towards fat and away from protein, and the studies saw no significant change in how much energy people burned, so the extra was not cancelled out.

A 2022 randomised trial then asked the opposite question in real life. Adults who usually slept under 6.5 hours got coaching to sleep longer. They managed about 1.2 extra hours a night, and their measured energy intake dropped by about 270 kcal a day compared with people who kept their usual habits. Intake was worked out from objective measures (doubly labelled water and body composition), not from food diaries, which is a strength.

In people who were short of sleep, more sleep went with eating less, on average.

What we do not know

These numbers are averages, and individuals vary widely. The lab studies were short and used sleep cuts much harsher than most people live with. The home trial lasted two weeks and did not measure weight change, so a 270 kcal gap is not a promise of weight loss. It is not yet clear whether sleeping longer for months changes weight or health markers, and the research on long-term effects is still thin. Where sources disagree or the evidence is thin, treat sleep as one helpful piece, not a fix.

What helps you sleep a little longer

The NHS suggests small, ordinary habits rather than anything clever:

  • Keep a regular sleep routine, including on days off.
  • Put screens away for about an hour before bed and wind down with something calm.
  • Avoid large meals, caffeine, alcohol and nicotine close to bedtime.
  • Keep the bedroom quiet, dark and cool.
  • If you are still awake after about 20 minutes, get up, do something relaxing and go back when sleepy.

None of this means eating less to make up for a bad night. Eat regular meals with some protein and fibre, and be kind to yourself on tired days.

When to ask someone

This guide is general information, not medical advice. If you often cannot sleep, wake unrefreshed, snore loudly, stop breathing at night or feel very sleepy in the day, talk to a doctor. The same goes if you have a medical condition, are pregnant or breastfeeding, take medication (especially for diabetes or blood pressure), or have or have had an eating disorder, before you change how you eat.

Sources

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