By Dr. Dave Patel · Published November 13, 2026 · 11 min read
Night eating syndrome (NES) is an eating disorder in which a large share of a person's food is eaten after the evening meal, or they repeatedly wake up during the night to eat, and they are aware of it. It usually comes with low appetite in the morning (often a skipped breakfast; see whether breakfast is the most important meal), trouble sleeping and a low or worsening mood in the evening, and it is thought to reflect a delay in the body's daily timing of hunger.
This guide covers the symptoms researchers use, how NES differs from sleep-related eating disorder and binge eating disorder, what the body-clock research shows, and how well each treatment works. NES is a health condition, not a failure of willpower, and it deserves care, not blame.
Important
Medical Disclaimer
This article is for informational purposes only and is not medical advice or a diagnosis. If you regularly eat at night and it distresses you, talk to your doctor or an eating disorder specialist. Don't stop or change sleep or mental health medication without speaking to the person who prescribed it.
What Is Night Eating Syndrome?
Night eating syndrome is a pattern in which eating shifts toward the end of the day and into the night, while the timing of sleep stays largely normal. Albert Stunkard and colleagues first described it in 1955, in a report on an eating pattern among certain patients with obesity.
Today the DSM-5, the manual clinicians use to diagnose mental health conditions, names NES as an example of other specified feeding or eating disorder (OSFED), as a 2022 systematic review notes. OSFED is the category for eating disorders that don't match the full criteria of anorexia, bulimia or binge eating disorder. The NHS describes OSFED as the most common eating disorder.
How common is NES itself? In a randomly selected sample of 2,097 adults, 1.5% met the definition used at the time, compared with 27% of 111 people who had had weight-loss surgery. A 2022 review by Lavery and Frum-Vassallo puts the general-population figure at about 1–2%. Using DSM-5 criteria, rates in eating disorder, obesity and bariatric surgery clinics range from 2.8% to 8.2%. Links between NES and body weight are mixed.
Night Eating Syndrome Symptoms
The four hallmarks are evening overeating, waking to eat, low morning appetite and insomnia. The most widely used definition is the set of proposed research criteria published by Kelly Allison and colleagues in the International Journal of Eating Disorders in 2010.
The core symptom is at least one of these:
- Evening hyperphagia: at least 25% of the day's food is eaten after the evening meal
- Nocturnal ingestions: waking up to eat at least twice a week
The person is aware of these episodes and can remember them. And at least three of these five features are present:
- Morning anorexia: little or no appetite in the morning, or skipping breakfast on four or more mornings a week. Here "anorexia" simply means a lack of appetite, not anorexia nervosa.
- A strong urge to eat between dinner and bedtime, or during the night
- Insomnia: trouble falling asleep or staying asleep on four or more nights a week
- A belief that you must eat in order to fall asleep or get back to sleep
- A mood that is often low, or that gets worse in the evening
Finally, the pattern causes real distress or gets in the way of daily life, has lasted at least three months, and isn't explained by a medical condition, a medication, substance use or another mental health condition.
In the studies behind these criteria, people with NES ate an average of 35% of their daily food after the evening meal, compared with 10% among people without it. Night-time episodes tend to be snack-sized.
Night Eating vs Sleep-Related Eating and Binge Eating
Night eating syndrome is often confused with two other conditions: sleep-related eating disorder (SRED) and binge eating disorder (BED). The quickest way to tell them apart is to ask whether you are fully awake and remember eating, and how much you eat at a time.
| Feature | Night eating syndrome | Sleep-related eating disorder | Binge eating disorder |
|---|---|---|---|
| What kind of condition | Eating disorder (OSFED in DSM-5) | Non-REM sleep parasomnia | Eating disorder |
| Awareness | Awake, aware and remembers eating | Little or no awareness or memory of eating | Awake and aware |
| Amount eaten | Usually snack or small-meal sized | Varies; can include odd food combinations or inedible items | Objectively large amounts |
| Loss of control | Not required | Eating is involuntary | Required |
| Main driver | Hunger, urges, or a belief that eating helps sleep | Not linked to hunger | Often cravings or emotional eating |
| When it happens | Evening and after waking at night | After partial arousal from sleep | Not tied to the night |
Table compiled from Allison et al. 2010 and the 2022 review by Lavery and Frum-Vassallo.
Sleep-Related Eating Disorder
Sleep-related eating disorder is a sleep disorder, not an eating disorder: eating after an arousal from sleep, with or without memory of it afterward. A review of nighttime eating disorders places the two at opposite ends of a spectrum, NES being a delay in meal timing with normal sleep timing, and notes that SRED often comes with other sleep disorders, especially parasomnias such as sleepwalking.
The causes differ too. A 2024 systematic review of 94 reports found that Z-drug sleeping pills, and certain benzodiazepines, antidepressants, antipsychotics and stimulants, may trigger SRED. If you find signs of eating you don't remember, tell the doctor who prescribes your medication rather than stopping it on your own.
Binge Eating Disorder
Binge eating disorder involves eating an objectively large amount of food with a sense of loss of control. NES episodes are usually smaller, and loss of control is not part of the definition. The two can overlap: across clinical studies, 18% to 50% of people with BED also meet NES criteria, according to the Lavery review. In a study of 11,604 adult twins, the genetic correlation between night eating and binge eating was 0.60, which suggests shared roots, though the conditions are still diagnosed separately.
What Causes Night Eating Syndrome?
The leading explanation is a circadian delay: the body clock that times appetite and meal-related hormones runs late, while the clock that times sleep stays on schedule. Stress, low mood and genetics appear to feed into it, but no single cause has been proven.
The clearest evidence comes from a 2009 inpatient study that compared 15 women with NES with 14 women without it, matched for age and body mass index (BMI), over three nights in a research unit. The women with NES ate their meals later, and several of their daily hormone rhythms were shifted:
| Measure | Shift in women with NES |
|---|---|
| Insulin rhythm | Delayed by 2.8 hours |
| Melatonin rhythm | Delayed by 1.1 hours |
| Leptin rhythm | Delayed by 1.0 hour |
| Cortisol rhythm | Delayed by 0.7 hours (not statistically significant) |
| Ghrelin rhythm | Advanced by 5.2 hours |
Insulin moves sugar from the blood into cells after a meal (our guide to blood sugar levels after eating shows the normal curve), leptin signals fullness and ghrelin signals hunger, so a shift in these rhythms changes when the body expects food. The authors concluded that NES "may be a disorder of circadian rhythm dysregulation", while noting that people with NES keep a normal sleep-wake cycle.
Serotonin is the other main lead. The biobehavioral model of NES proposes that genetics plus stress lower serotonin activity in the brain, which disrupts daily rhythms and weakens the feeling of fullness. It is the rationale its author gives for SSRI antidepressants. Depression, anxiety and insomnia are common in NES, and the Lavery review notes that stress and psychiatric symptoms often come before night eating and help keep it going.
How Night Eating Syndrome Is Treated
Night eating syndrome is treatable, but the research is thin. A 2025 systematic review could include only five randomized controlled trials. It judged the certainty of the evidence for every outcome as low, although sertraline showed the most improvement. The main options are below.
| Treatment | Best study so far | What it found | Strength of evidence |
|---|---|---|---|
| Sertraline (an SSRI antidepressant) | 8-week placebo-controlled trial, 34 adults | 71% responded vs 18% on placebo; fewer night-time awakenings and ingestions | One small RCT |
| Escitalopram (an SSRI) | 12-week placebo-controlled trial, 40 adults | Not better than placebo on the Night Eating Questionnaire | One small RCT, negative |
| Cognitive behavioral therapy (CBT) | 10-session pilot, 25 adults | Share of food after dinner fell from 35.0% to 24.9%; night-time eating from 8.7 to 2.6 times a week | Pilot, no control group |
| Progressive muscle relaxation | Pilot RCT, 44 adults | Bigger drop in food eaten after the evening meal than education alone | Small pilot RCTs |
| Morning bright light therapy | Pilot, 15 adults | Less night eating, low mood and sleep disturbance after two weeks | Pilot, no control group |
Medication
SSRIs have the most support, and sertraline the strongest trial, though escitalopram did no better than placebo, so not every SSRI has shown the same effect. A review of NES treatment by the University of Pennsylvania group concluded that medication has the most evidence so far. Other drugs, such as topiramate, have only case reports or small studies, and the Lavery review notes that topiramate's side effects may outweigh its benefits. Medication decisions belong with a doctor.
Therapy, Relaxation and Light
CBT for NES targets the beliefs that keep night eating going, such as "I can't sleep without eating", along with regular daytime eating and sleep habits. In the pilot, awakenings, mood and quality of life improved along with night eating. In a one-week trial of 20 adults, daily progressive muscle relaxation lowered stress and anxiety and was linked to more hunger in the morning and less in the evening. The light therapy pilot used 10,000 lux of bright light each morning. None of these has yet been confirmed in a large controlled trial.
Note
What the Research Can't Tell You Yet
Each study in the table above had fewer than 50 participants, and long-term follow-up data are lacking. Nobody yet knows which treatment works best as a first step, whether combining therapy and medication helps more, or how long improvements last.
When to Get Help for Night Eating
Talk to your doctor if night eating has gone on for months, if it upsets you, or if it comes with poor sleep or low mood. You don't need to meet every criterion to deserve support, and a doctor can also check for other causes, such as a sleep disorder, a medication side effect or depression.
These steps can make the first appointment more useful:
Keep a short record
Note whether you remember eating
List your medications
Mention mood and stress
Get help right away if night eating comes with thoughts of harming yourself or severe depression. In the UK, the NHS eating disorders page advises seeing a GP as soon as you can, and lists the eating disorder charity Beat's helpline, 0808 801 0677. In the US, your primary care doctor, a psychiatrist or the National Eating Disorders Association (NEDA) can point you to eating disorder care.
Night Eating Is About Timing, Not Willpower
Night eating syndrome is a shift in when the body expects food, tangled up with sleep, stress and mood, so treating it as a lack of discipline misses what the research shows. The treatments with evidence target that timing and the mood and sleep problems around it. Gentler approaches built on hunger and fullness cues, the idea behind what intuitive eating teaches, haven't been studied in NES, so treat them as a complement to professional care, not a substitute.
General sleep tips and supplements, such as those in our guide to magnesium for sleep, haven't been tested as treatments for NES either. The steps with evidence behind them are a proper assessment, then treatment such as sertraline, CBT, relaxation training or morning light, chosen with a clinician who understands both eating and sleep.