Intermittent fasting and sleep: why you lie awake on an empty stomach and what you can change
You fast with discipline, and still you are wide awake at three in the morning. That is rarely a lack of willpower. Often it is a body that reads an empty eating window as an alarm signal.
Fasting is usually discussed as a nutrition topic. I also see it as a stress topic. Your body does not distinguish between chosen restraint and real scarcity. It responds to both with the same alarm system.
It is 3:12 a.m. You are awake for no reason. No noise, no dream, just a clear head and a heart beating a little faster than it needs to. You turn over. Nothing happens. Sleep does not come back.
Maybe you deliberately stopped eating early in the evening. Maybe you have been shrinking your window more and more over the past weeks because it felt so good at first. And now you are wondering whether fasting simply is not for you.
I want to offer you a different question: what if, in this moment, your body is not working against you but for you? What if it is simply responding to a signal you sent it without realizing?
Four questions before you doubt fasting
If you lie awake at night while fasting, it is worth first taking a calm look at your everyday life rather than at your discipline:
- How many hours lie between your last meal and going to bed?
- How high is your stress level right now, at work and in private life?
- When do you drink your last coffee?
- How long has the restless sleep been going on, and did it start with fasting?
In short: sleeplessness while fasting is often not a question of character, but of timing, load and starting point.
What to expect in this article
- Why an empty stomach can keep you awake
- Cortisol, adrenaline and orexin explained
- What studies show about fasting and sleep
- What Ramadan reveals about timing
- How meal times set the internal clock
- What belongs on your evening plate
- The vicious cycle of hunger and sleep loss
- Three levers for calmer nights
How I label the evidence
Clinical study Randomized studies or meta-analyses in humans. The strongest evidential weight.
Human observation Cohorts, non-randomized sleep laboratory studies, reviews. They show associations, not necessarily causes.
Animal model Data from animal studies. Biologically plausible, not automatically transferable to humans.
Cellular level Data from cell cultures or isolated neurons. They explain mechanisms but do not prove a clinical effect.
Why can an empty stomach keep you awake at night?
Imagine your body as a house with a very watchful alarm system. It has one single job: making sure the brain always gets enough energy. The brain is a demanding tenant. It needs stable blood sugar at night, too.
When energy drops, the alarm goes off. Not with a siren, but with hormones. The liver is told to release sugar, the adipose tissue to mobilize fat. To do this, the body mainly uses two signals: cortisol from the adrenal cortex and adrenaline from the adrenal medulla.
Both hormones have a side effect that is useful during the day and disruptive at night. They promote wakefulness. They raise your pulse, sharpen your attention and switch the brain into search mode. From an evolutionary perspective this makes sense: if you are hungry, you should not be sleeping deeply, you should be finding food.
Empty window, shrinking reserves
The liver's glycogen stores get smaller overnight. With long or very strict fasting, a lot of exercise or a lot of stress, this can happen faster.
The hypothalamus registers scarcity
Falling glucose and leptin together with rising ghrelin can stimulate wakefulness centers such as the orexin neurons.
The stress axis kicks in
Via the HPA axis, cortisol rises to stimulate glucose production in the liver.
Sympathetic nervous system and adrenaline
The adrenal medulla can release adrenaline. Heart rate and alertness go up.
Waking in the second half of the night
Sleep becomes lighter. Many people experience this as suddenly waking between two and four a.m., often with rumination.
How strongly this cascade unfolds varies greatly from person to person. In healthy, well-nourished people with a moderate eating window, it is often barely noticeable. In people with high baseline stress, little sleep reserve or very strict fasting, it can become clearly noticeable.
Clinical study Martin Bergendahl and colleagues at the University of Virginia studied eight healthy men in 1996 on a normal eating day and on the fifth day of a water fast, in random order, with blood samples taken every five minutes over 24 hours.
Daily cortisol production rose 1.8-fold during fasting, mainly because more cortisol was released per secretory burst. The daily peak also shifted from the morning to the early afternoon.
What this means for you: a fast lasting several days is not the same as 16:8. The study does show, however, that energy scarcity can measurably nudge the stress axis.
Bergendahl M et al. J Clin Endocrinol Metab. 1996. DOI: 10.1210/jcem.81.2.8636290Orexin: the wake signal that listens to hunger
There is a messenger that is rarely mentioned in this story. It is called orexin, sometimes also hypocretin. Orexin neurons in the hypothalamus keep you awake. When they are missing, the sleep disorder narcolepsy develops.
Animal model Cellular level Akihiro Yamanaka and the team led by Takeshi Sakurai in Tsukuba showed in 2003 in the journal Neuron how orexin neurons respond to energy status.
Isolated orexin neurons were inhibited by glucose and leptin and stimulated by the hunger hormone ghrelin. Mice lacking these neurons did not respond to fasting with the usual increase in wakefulness and activity.
What this means for you: in humans, this pathway has not been shown in the same detail. It is biologically plausible, however, that an empty stomach can send a wake signal to the brain via orexin.
Yamanaka A et al. Neuron. 2003. DOI: 10.1016/s0896-6273(03)00331-3Waking at night while fasting is often interpreted as weakness. Through the KPNI lens, it looks more like a sign of a working protective system. Your body is not saying: you cannot do this. It is saying: the dose does not match your current load.
And now you know why a fasting plan that is perfect for your friend can wake you up at three in the morning.
What do studies show about intermittent fasting and sleep?
Maybe you have read that intermittent fasting improves sleep. Maybe also the opposite. You can find both online. The research is more honest and also a little less spectacular.
On average, a moderate eating window changes sleep only a little. That is reassuring. But it does not mean nobody sleeps worse. Averages can hide strong reactions in individuals.
Meta-analysis He Li and colleagues analyzed 13 studies in Frontiers in Nutrition in 2026, covering a total of 544 people with type 2 diabetes who had tried time-restricted eating.
They found signs of slightly lower long-term blood sugar and a smaller waist circumference. For sleep parameters, there was no significant effect in either direction.
What this means for you: on average, time-restricted eating seems neither to clearly improve nor to clearly worsen sleep. How it works for you depends strongly on how you do it.
Li H et al. Front Nutr. 2026. DOI: 10.3389/fnut.2026.1906991RCT Kristan Amendola and the team led by Jennifer Heisz at McMaster University had twenty-three young women do three days of time-restricted eating and three days of alternate-day fasting in 2026.
Hunger rose under both approaches. Mood was initially worse with full-day fasting, and satisfaction was higher with time-restricted eating. Subjective sleep quality did not change significantly with either form.
What this means for you: in the short term, an eating window seems to be well tolerated by many. Stricter forms, however, may cost more mood and energy.
Amendola K et al. PLoS One. 2026. DOI: 10.1371/journal.pone.0356690Even in shift workers, whose sleep is already under strain, a 2025 meta-analysis of six randomized studies found no significant effect of time-restricted eating on total sleep time or sleep efficiency. The authors rated the certainty of the evidence as very low.
And there is data pointing the other way. In a small open pilot study by Andreas Michalsen and colleagues in Essen from 2003, nighttime arousals decreased in 15 non-obese adults after one week of modified fasting. Participants reported better sleep and more daytime energy. There was, however, no control group.
Fasting is often well tolerated when
- the eating window is moderate, roughly 10 to 12 hours
- the last meal is filling and nutrient-dense
- your sleep was already stable beforehand
- your stress level is manageable
- you are not combining a large calorie deficit with a lot of exercise at the same time
Sleep is more likely to suffer when
- you go to bed hungry
- the window is very short or very late
- you are exhausted or under a lot of ongoing stress
- coffee is meant to bridge the hunger gap
- you take medication that lowers blood sugar
The question is not whether intermittent fasting is good or bad for sleep. The question is whether your fasting plan fits your nervous system. The same tool can feel calming to a relaxed person and alarming to a stressed one.
And now you know why you can read study headlines about fasting and sleep with a little more composure.
Why does the timing of the eating window matter so much?
Do you know the feeling after a long-haul flight? You are tired, but not ready for sleep. Hungry, but at the wrong time. A similar small jet lag can arise when you shift your meal times significantly. Only you do not notice it as jet lag, but as a restless night.
Your body does not have just one clock. In the brain sits the master clock, which listens mainly to light. In the liver, gut, muscles and adipose tissue sit peripheral clocks. These listen strongly to food. When the master and peripheral clocks drift apart, this is called internal desynchronization.
Laboratory study Sophie Wehrens and the team led by Jonathan Johnston at the University of Surrey delayed all three meals by five hours in ten healthy young men in 2017.
The master clock, measured by melatonin and cortisol, remained unchanged. The blood sugar rhythm, however, shifted by roughly five and a half hours, and the clock in adipose tissue by almost one hour.
What this means for you: late eating can decouple your organ clocks from the light clock. This is one possible piece of the puzzle as to why late meals and restless sleep sometimes go together.
Wehrens SMT et al. Curr Biol. 2017. DOI: 10.1016/j.cub.2017.04.059What Ramadan reveals about sleep and timing
Ramadan is a natural experiment. For one month, millions of people eat and drink only between sunset and sunrise. Meals move into the night. That makes it interesting for the question of whether the amount of energy or rather the timing influences sleep.
Human observation Rachida Roky and colleagues from Casablanca studied eight healthy young men before, during and after Ramadan using polysomnography in 2001.
During Ramadan, falling asleep took longer, deep sleep and REM sleep decreased, and core body temperature stayed higher at night. Since energy intake was maintained, the researchers attributed the changes to the reversal of eating and drinking times.
What this means for you: not only how much you eat, but also when you eat, can help shape the architecture of your sleep.
Roky R et al. J Sleep Res. 2001. DOI: 10.1046/j.1365-2869.2001.00269.xA contrasting finding is interesting. In 2013, Ahmed BaHammam and colleagues in Riyadh deliberately kept sleep times and calorie intake constant in eight healthy volunteers during Ramadan. Under these conditions, only the REM share decreased. Sleep onset, arousals, sleep efficiency and daytime sleepiness remained stable.
A 2025 meta-analysis of 14 studies found shorter sleep duration and lower sleep efficiency during Ramadan, while subjective sleep quality was in part rated better. So the picture is mixed. One pattern runs through it, though: the more the rhythm is shifted, the more likely sleep is to suffer.
A randomized crossover study by Humaira Jamshed and Courtney Peterson from 2019 fits this picture. Eleven adults with overweight ate for four days either between 8 a.m. and 2 p.m. or between 8 a.m. and 8 p.m. The early window lowered average blood sugar over 24 hours and changed the daily course of cortisol as well as the activity of several clock genes. So the body does appear to read meal times as a time cue.
Schematic: gap between last meal and sleep
Simplified orientation based on studies on meal timing and sleep onset as well as my clinical experience. Not a fixed value, but a starting point to experiment with.
A shorter window is often automatically considered a better window. For your sleep, the position often matters more than the length. A twelve-hour window that fits your day can be more restful than a six-hour window that sends you to bed hungry.
And now you know why, with sleep problems, I first look at the time of your last meal and only then at the length of your fasting break.
What belongs on your evening plate when you fast?
Many people who fast deliberately eat few carbohydrates in the evening. That sounds disciplined. For sleep, however, it can backfire. Carbohydrates are not just energy, they also influence how easily your brain finds its way into sleep.
One reason is the amino acid tryptophan. From it, the body makes serotonin and later melatonin. Carbohydrates raise insulin. Insulin directs competing amino acids into the muscles, so that tryptophan can reach the brain more easily.
Clinical study Ahmad Afaghi, Helen O'Connor and Chin Moi Chow from Sydney gave twelve healthy young men high-carbohydrate rice meals with a high or low glycemic index in random order in 2007.
After the high glycemic index meal four hours before bedtime, they fell asleep after a mean of 9 minutes, and after the low index version after 17.5 minutes. The same meal one hour before bedtime shortened sleep onset less markedly.
What this means for you: a carbohydrate-containing meal a few hours before bed may make it easier to fall asleep. Whether this also applies to people with sleep disorders remains open.
Afaghi A et al. Am J Clin Nutr. 2007. DOI: 10.1093/ajcn/85.2.426RCT, secondary analysis Marie-Pierre St-Onge and colleagues at Columbia University analyzed the diet and sleep of 26 normal-weight adults in the sleep laboratory in 2016.
More fiber was associated with more deep sleep. More saturated fat was linked to less deep sleep, and a higher share of sugar and other fast carbohydrates to more nighttime arousals.
What this means for you: it is not about carbohydrates yes or no, but about their quality. Fiber-rich carbohydrates might support sleep better than sweets.
St-Onge MP et al. J Clin Sleep Med. 2016. DOI: 10.5664/jcsm.5384The vicious cycle of hunger and sleep loss
Here a cycle closes that many people know. You sleep poorly because you go to bed hungry. The next day, the hunger is even greater. Fasting feels harder. You push through, go to bed hungry again, and the night is restless again.
RCT Karine Spiegel, Esra Tasali, Plamen Penev and Eve Van Cauter from Chicago compared two nights of restricted sleep with two nights of extended sleep in twelve healthy young men in 2004.
After restricted sleep, the satiety hormone leptin was 18 percent lower and the hunger hormone ghrelin 28 percent higher. Hunger and appetite increased by 24 and 23 percent, especially for calorie-dense and carbohydrate-rich foods.
What this means for you: poor sleep can make fasting noticeably more strenuous the next day. That is why sleep is not a side issue, but part of your fasting plan.
Spiegel K et al. Ann Intern Med. 2004. DOI: 10.7326/0003-4819-141-11-200412070-00008Many people think: if I eat in the evening, I ruin my fast. A well-chosen dinner can make your fasting more sustainable, because restful sleep may mean less hunger and more calm the next day.
And now you know why the last meal of your day may be the most important one for your night.
How does KPNI view the interplay of fasting and sleep?
Clinical Psychoneuroimmunology does not look at a single organ, but at networks. When it comes to fasting and sleep, four systems interlock. An imbalance in one can pull the others along.
Nervous system
Orexin neurons and the sympathetic nervous system respond to energy scarcity. They keep the brain alert. If your nervous system is already revved up by ongoing stress, even a small additional shortage can be enough to disturb sleep.
Hormonal system
Cortisol should be low at night and rise in the morning. Fasting can increase cortisol production and shift its curve. In women, the cycle adds another layer: in the second half of the cycle, the body often reacts more sensitively to energy gaps.
Metabolism
The liver keeps blood sugar stable at night. If its glycogen stores are small, for example after very low-carbohydrate days or a lot of training, glucose production has to step in earlier. For that, the body needs exactly the hormones that promote wakefulness.
Immune system
Sleep is an important phase for immune regulation. Disturbed sleep is associated with a greater readiness for inflammation. If fasting keeps robbing you of deep sleep, part of its inflammation-dampening potential might be lost.
Well supported: fasting can increase cortisol. Sleep loss increases hunger and ghrelin. Meal times can shift peripheral clocks. Shifted meals during Ramadan are associated with altered sleep.
Mechanistically plausible, still thin in humans: that orexin keeps you awake at night during short-term intermittent fasting, and that exactly this cascade explains the typical waking around three a.m.
Clinical observation: people with high stress and very strict fasting tell me more often about trouble staying asleep. That is experience, not proof.
One special case deserves attention: people with diabetes who take glucose-lowering medication. For them, fasting can increase the risk of nighttime hypoglycemia. A 1993 study at the Steno Diabetes Center in people with type 1 diabetes showed that the release of adrenaline and noradrenaline during nighttime hypoglycemia tended to be even stronger than during the day. If you want to fast in this situation, it belongs under medical supervision.
And now you know why I never look at fasting and sleep separately, but as two sides of the same stress axis.
Good sleep is not a luxury. It is the freedom to start your day with a clear head in the morning. A fasting plan that takes this freedom away from you is not your plan. It is just a plan.
Three levers for calmer nights while fasting
You do not have to give up fasting. You can adjust it so that it does not get in the way of your sleep. These three levers are not a therapy, but a direction I consider sensible.
Place the window before bedtime, not in the night
To start, finish your last meal about three to four hours before sleep. If you go to bed hungry, move the end of your window one hour later and observe for a week what happens. A regular rhythm seems more important here than a perfect time.
Build a filling evening meal
Combine protein-rich foods such as eggs, legumes or yogurt with fiber-rich carbohydrates such as potatoes, oats, millet or brown rice and plenty of vegetables. Pumpkin seeds and oat flakes provide additional tryptophan. Sugar, a lot of saturated fat and alcohol in the evening are best left out.
Match the fasting dose to your load
In stressful weeks, with poor sleep or in the second half of your cycle, a longer twelve-hour window may be wiser than a strict 16:8. Drink coffee only in the morning and do not bridge hunger with caffeine. Fasting is meant to be a stimulus, not additional ongoing stress.
Self-check: is your fasting too much for your nervous system right now?
- Since you started fasting, you regularly wake up between two and four a.m.
- You often go to bed with a growling stomach.
- At night you are awake and wired instead of tired.
- You need more coffee in the morning than before to get going.
- Your daytime hunger has become greater rather than smaller.
- You are currently under a lot of pressure at work or in private life.
- You take medication that lowers blood sugar.
If you nod at several points, that is no reason to worry. It is a signal to reduce the fasting dose and give your sleep priority. If sleep problems persist for several weeks, a medical evaluation is worthwhile, because thyroid function, iron status, hormones or sleep apnea can also play a role.
And now you know why the smartest fasting plan is sometimes the one that ends an hour later.
Frequently asked questions about intermittent fasting and sleep
Can intermittent fasting cause sleep problems?
For many people, a moderate eating window changes sleep very little on average. A 2026 meta-analysis of 13 studies with 544 people with type 2 diabetes found no significant effect on sleep parameters. Some individuals, however, respond clearly. Fasting that is very late, very strict or combined with a lot of stress in particular might activate the stress axis at night and make it harder to fall or stay asleep. What seems to matter is less the fasting itself and more the timing, the strictness and your starting point.
Why do I wake up at three in the morning when I fast?
One possible explanation is your body's counterregulation. When energy runs low, it can release cortisol and adrenaline to keep blood sugar stable. Both hormones promote wakefulness. In a randomized study from 1996, daily cortisol production in healthy men rose 1.8-fold after five days of water fasting. Short intermittent fasting is not the same as a five-day fast. The principle does show, though, that an energy shortage can nudge the stress axis. Other reasons can include hunger, stress, alcohol or an internal clock that is already shifted.
What is orexin and what does it have to do with fasting?
Orexin is a messenger from the hypothalamus that promotes wakefulness. In a 2003 animal study in mice, orexin neurons were inhibited by glucose and leptin and stimulated by the hunger hormone ghrelin. Mice lacking these neurons did not respond to fasting with increased wakefulness and activity. In humans, this connection has not been shown in the same detail. It is biologically plausible, however, that an empty stomach sends a signal via orexin: stay awake and look for food.
Is an early or a late eating window better for sleep?
Direct comparison studies on sleep are still scarce. Research on the internal clock suggests some benefit from an eating window that ends well before bedtime and is not pushed into the night. In a 2017 laboratory study, eating five hours later shifted the blood sugar rhythm by more than five hours and the clock in adipose tissue by almost one hour. A very early window that sends you to bed hungry can also be unfavorable for some people, though. My view: finishing your last meal about three to four hours before sleep is a good starting point for many.
Should I eat carbohydrates in the evening if I fast and sleep poorly?
For some people this can make sense. In a small study in the American Journal of Clinical Nutrition from 2007, twelve healthy men fell asleep after a mean of 9 instead of 17.5 minutes following a high-carbohydrate meal with a high glycemic index four hours before bedtime. At the same time, a 2016 study found that a lot of sugar was associated with more nighttime arousals and more fiber with more deep sleep. A sensible middle ground can be an evening meal with complex carbohydrates, protein and fiber, not a plate of sweets.
How does Ramadan fasting affect sleep?
During Ramadan, people eat and drink only between sunset and sunrise. A 2001 sleep laboratory study showed longer sleep onset, less deep sleep and less REM sleep during Ramadan. The researchers attributed this to the reversal of eating and drinking times, not to lower energy intake. A 2013 study with fixed sleep times and a fixed calorie intake, by contrast, found only a lower REM share. This suggests that the shifted rhythm in particular may influence sleep.
Can poor sleep make fasting harder?
This has been studied fairly well. In a randomized crossover study in the Annals of Internal Medicine from 2004, two nights of restricted sleep lowered the satiety hormone leptin by 18 percent and raised the hunger hormone ghrelin by 28 percent. Hunger and appetite increased by 24 and 23 percent, especially for calorie-dense, carbohydrate-rich foods. If you sleep poorly, you are fasting against stronger hunger. This can create a cycle in which poor sleep makes fasting harder and strict fasting makes sleep harder.
For whom is intermittent fasting less suitable when sleep is a problem?
Caution makes sense with marked exhaustion, high ongoing stress, existing sleep maintenance problems, a history of eating disorders, pregnancy and breastfeeding, and diabetes treated with glucose-lowering medication. In diabetes, fasting can increase the risk of nighttime hypoglycemia, and the nighttime hormonal response to it can be strong. In these situations, fasting should only happen after medical consultation and preferably in a gentle form. Sometimes it is wiser to stabilize sleep first and then think about an eating window.
Can fasting also improve sleep?
For some people this seems possible. In an open pilot study from 2003 with 15 non-obese adults, nighttime arousals and periodic leg movements decreased after one week of modified fasting, and participants reported better sleep. There was, however, no control group. A 2026 randomized crossover study with 23 young women found no change in subjective sleep quality under either time-restricted eating or alternate-day fasting. So fasting is not a sleeping pill, but it can be well tolerated when timing and starting point fit.
More from the Fasting Guide
- Fasting for beginners: how to get started
- Intermittent fasting 16:8: what happens in the body
- Fasting with exhaustion and adrenal stress
- Fasting for women and the cycle
- Fasting during menopause
- Cravings during intermittent fasting
- Fasting, blood sugar and insulin resistance
- Fasting with type 2 diabetes
- Breaking your fast well: the first meal
- What breaks a fast?
- Intermittent fasting and iron deficiency
- Autophagy: when does it begin?
Where this topic touches other areas
Sleep is a cross-cutting topic. If you recognized yourself in this article, these neighboring topics are worth a look.
Chronobiology and morning light
How morning light can set the master clock.
Falling asleep4-7-8 breathing for falling asleep
A simple technique that may calm the nervous system.
Nervous systemBreathing techniques and the vagus nerve
How breathing can influence the stress axis.
CortisolAshwagandha, cortisol and stress
What the studies on this adaptogen show.
Medicinal plantsValerian and passionflower for sleep problems
Herbal options, honestly put into context.
MagnesiumWhich magnesium is best?
The forms compared, including with a view to sleep.
Sources
All references were checked via PubMed and linked with their DOI. The study type is given in square brackets so you can assess the evidential weight yourself.
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- Yamanaka A, Beuckmann CT, Willie JT, Hara J, Tsujino N, Mieda M, Tominaga M, Yagami K, Sugiyama F, Goto K, Yanagisawa M, Sakurai T. Hypothalamic orexin neurons regulate arousal according to energy balance in mice. Neuron. 2003;38(5):701-13. DOI: 10.1016/s0896-6273(03)00331-3 [In vivo, mouse, supplemented by in vitro, isolated neurons]
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- Michalsen A, Schlegel F, Rodenbeck A, Lüdtke R, Huether G, Teschler H, Dobos GJ. Effects of short-term modified fasting on sleep patterns and daytime vigilance in non-obese subjects: results of a pilot study. Ann Nutr Metab. 2003;47(5):194-200. DOI: 10.1159/000070485 [Real-world pilot study, open label, no control group, n=15]
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- BaHammam AS, Almushailhi K, Pandi-Perumal SR, Sharif MM. Intermittent fasting during Ramadan: does it affect sleep? J Sleep Res. 2014;23(1):35-43. DOI: 10.1111/jsr.12076 [Real-world observational study, polysomnography, n=8]
- El-Jaziz A, Lotfi S. Sleep patterns among athletes and non-athletes during Ramadan intermittent fasting: systematic review, meta-analysis and meta-regression. Ann Ig. 2025;37(2):266-280. DOI: 10.7416/ai.2025.2675 [Meta-analysis, 14 studies]
- Jamshed H, Beyl RA, Della Manna DL, Yang ES, Ravussin E, Peterson CM. Early time-restricted feeding improves 24-hour glucose levels and affects markers of the circadian clock, aging, and autophagy in humans. Nutrients. 2019;11(6):1234. DOI: 10.3390/nu11061234 [RCT, crossover, n=11]
- Afaghi A, O'Connor H, Chow CM. High-glycemic-index carbohydrate meals shorten sleep onset. Am J Clin Nutr. 2007;85(2):426-30. DOI: 10.1093/ajcn/85.2.426 [RCT, crossover, randomized order, n=12]
- St-Onge MP, Roberts A, Shechter A, Choudhury AR. Fiber and saturated fat are associated with sleep arousals and slow wave sleep. J Clin Sleep Med. 2016;12(1):19-24. DOI: 10.5664/jcsm.5384 [RCT, crossover, secondary analysis, n=26]
- Spiegel K, Tasali E, Penev P, Van Cauter E. Brief communication: Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Ann Intern Med. 2004;141(11):846-50. DOI: 10.7326/0003-4819-141-11-200412070-00008 [RCT, crossover, n=12]
- Bendtson I, Rosenfalck AM, Binder C. Nocturnal versus diurnal hormonal counterregulation to hypoglycemia in type 1 (insulin-dependent) diabetic patients. Acta Endocrinol (Copenh). 1993;128(2):109-15. DOI: 10.1530/acta.0.1280109 [Pathophysiology, clamp study, n=10, type 1 diabetes]